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1
Wang, H. B., H. J. Zhang, L. L. Song, L. Zhu, M. Chen, G. J. Ren, G. H. Liu, and G. H. Zhao. "Morphological and molecular confirmation of the validity of Trichuris rhinopiptheroxella in the endangered golden snub-nosed monkey (Rhinopithecus roxellana)." Journal of Helminthology 93, no. 05 (July 10, 2018): 601–7. http://dx.doi.org/10.1017/s0022149x18000500.
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AbstractThe golden snub-nosed monkey (Rhinopithecus roxellana) is an endangered species endemic to China. Relatively little is known about the taxonomic status of soil-transmitted helminths (STH) in these monkeys. Trichuris spp. (syn. Trichocephalus) are among the most important STHs, causing significant socio-economic losses and public health concerns. To date, five Trichuris species have been reported in golden monkeys, including a novel species, T. rhinopiptheroxella, based on morphology. In the present study, molecular and morphological analysis was conducted on adult Trichuris worms obtained from a dead golden snub-nosed monkey, to better understand their taxonomic status. Morphology indicated that the adult Trichuris worms were similar to T. rhinopiptheroxella. To further ascertain their phylogenetic position, the complete mitochondrial (mt) genome of these worms was sequenced and characterized. The mt genome of T. rhinopiptheroxella is 14,186 bp, encoding 37 genes. Phylogenetic analysis based on the concatenated amino acids of 12 protein-coding genes (with the exception of atp8) indicated that T. rhinopiptheroxella was genetically distinct and exhibited 27.5–27.8% genetic distance between T. rhinopiptheroxella and other Trichuris spp. Our results support T. rhinopiptheroxella as a valid Trichuris species and suggest that mt DNA could serve as a marker for future studies on the classification, evolution and molecular epidemiology of Trichuris spp. from golden snub-nosed monkeys.
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Maier, M. A., E. Olivier, S. N. Baker, P. A. Kirkwood, T. Morris, and R. N. Lemon. "Direct and Indirect Corticospinal Control of Arm and Hand Motoneurons in the Squirrel Monkey (Saimiri sciureus)." Journal of Neurophysiology 78, no. 2 (August 1, 1997): 721–33. http://dx.doi.org/10.1152/jn.1997.78.2.721.
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Maier, M. A., E. Olivier, S. N. Baker, P. A. Kirkwood, T. Morris, and R. N. Lemon. Direct and indirect corticospinal control of arm and hand motoneurons in the squirrel monkey ( Saimiri sciureus). J. Neurophysiol. 78: 721–733, 1997. Anatomic evidence suggests that direct corticomotoneuronal (CM) projections to hand motoneurons in the New World squirrel monkey ( Saimiri sciureus) are weak or absent, but electrophysiological evidence is lacking. The nature of the corticospinal linkage to these motoneurons was therefore investigated first with the use of transcranial magnetic stimulation (TMS) of the motor cortex under ketamine sedation in five monkeys. TMS produced early responses in hand muscle electromyogram, but thresholds were high (compared with macaque monkey) and the onset latency was variable. Second, stimulation of the pyramidal tract (PT) was carried out with the use of chronically implanted electrodes in ketamine-sedated monkeys; this produced more robust responses that were markedly facilitated by repetitive stimulation, with little decrease in latency on the third compared with the first shock. Finally, postsynaptic potentials were recorded intracellularly from 93 arm and hand motoneurons in five monkeys under general chloralose anesthesia. After a single PT stimulus, the most common response was a small, slowly rising excitatory postsynaptic potential (EPSP), either alone (35 of 93 motoneurons) or followed by an inhibitory postsynaptic potential (39 of 93). The segmental delay of the early EPSPs was within the monosynaptic range (mean 0.85 ms); however, the rise time of these EPSPs was slow (mean 1.3 ms) and their amplitude was small (mean 0.74 mV). These values are significantly slower and smaller than EPSPs in a comparable sample of Old World macaque monkey motoneurons. The results show that CM connections do exist in the squirrel monkey but that they are weak and possibly located on the remote dendrites of the motoneurons. The findings are consistent with earlier anatomic studies. Repetitive PT stimulation produced large, late EPSPs in some motoneurons, suggesting that, in this species, there are relatively strong nonmonosynaptic pathways linking the corticospinal tract to hand motoneurons.
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Fujii, Naotaka, Hajime Mushiake, and Jun Tanji. "Intracortical Microstimulation of Bilateral Frontal Eye Field." Journal of Neurophysiology 79, no. 4 (April 1, 1998): 2240–44. http://dx.doi.org/10.1152/jn.1998.79.4.2240.
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Fujii, Naotaka, Hajime Mushiake, and Jun Tanji. Intracortical microstimulation of bilateral frontal eye field. J. Neurophysiol. 79: 2240–2244, 1998. We trained two monkeys to perform a fixation task. Intracortical microstimulation (ICMS) was applied to the monkey frontal eye field (FEF) while monkeys were fixating on one of five fixation LEDs. The ICMS was applied in two different manners. Under the single stimulation condition, ICMS was delivered to either right or left FEF. Under the paired stimulation condition, bilateral FEF were successively stimulated with an interval of 30–250 ms. The single stimulation elicited contraversive saccades. As reported previously, these saccades were not much affected by initial eye positions, maintaining the same vector. In contrast, the paired stimulation elicited double-step saccades. The first of the paired stimulation elicited constant vector saccades, but the second of the paired stimulation evoked saccades whose vector varied greatly depending on the eye position at the start of individual saccades. The second saccades, starting from various initial positions, were directed to the endpoint of saccades that were elicited from the same FEF site under the single stimulation condition. Endpoints of second saccades varied little despite variations of intervals of the stimulation pairs, ranging from 60 to 150 ms. On the basis of these observations, we propose a novel view that the FEF is involved in directing saccades to an internally referenced visual target.
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Leendertz, Siv Aina J., Sandra Junglen, Claudia Hedemann, Adeelia Goffe, Sebastien Calvignac, Christophe Boesch, and Fabian H. Leendertz. "High Prevalence, Coinfection Rate, and Genetic Diversity of Retroviruses in Wild Red Colobus Monkeys (Piliocolobus badius badius) in Taï National Park, Côte d'Ivoire." Journal of Virology 84, no. 15 (May 19, 2010): 7427–36. http://dx.doi.org/10.1128/jvi.00697-10.
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ABSTRACT Simian retroviruses are precursors of all human retroviral pathogens. However, little is known about the prevalence and coinfection rates or the genetic diversity of major retroviruses—simian immunodeficiency virus (SIV), simian T-cell lymphotropic virus type 1 (STLV-1), and simian foamy virus (SFV)—in wild populations of nonhuman primates. Such information would contribute to the understanding of the natural history of retroviruses in various host species. Here, we estimate these parameters for wild West African red colobus monkeys (Piliocolobus badius badius) in the Taï National Park, Côte d'Ivoire. We collected samples from a total of 54 red colobus monkeys; samples consisted of blood and/or internal organs from 22 monkeys and additionally muscle and other tissue samples from another 32 monkeys. PCR analyses revealed a high prevalence of SIV, STLV-1, and SFV in this population, with rates of 82%, 50%, and 86%, respectively. Forty-five percent of the monkeys were coinfected with all three viruses while another 32% were coinfected with SIV in combination with either STLV or SFV. As expected, phylogenetic analyses showed a host-specific pattern for SIV and SFV strains. In contrast, STLV-1 strains appeared to be distributed in genetically distinct and distant clades, which are unique to the Taï forest and include strains previously described from wild chimpanzees in the same area. The high prevalence of all three retroviral infections in P. b. badius represents a source of infection to chimpanzees and possibly to humans, who hunt them.
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Heffner, H. E., and R. S. Heffner. "Hearing loss in Japanese macaques following bilateral auditory cortex lesions." Journal of Neurophysiology 55, no. 2 (February 1, 1986): 256–71. http://dx.doi.org/10.1152/jn.1986.55.2.256.
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The hearing ability of five Japanese macaques (Macaca fuscata) was assessed following two-stage bilateral auditory cortex lesions. The animals were tested using a shock-avoidance procedure with a conditioned-suppression procedure used for comparison in two cases. The animals initially were unable to respond to sound, and the first signs of hearing appeared as late as 13 wk after surgery. Hearing levels improved gradually over time, with maximal recovery reached at 24-35 wk after surgery. Recovery was most pronounced for low frequencies (63-250 Hz) and very high frequencies (32 kHz), which generally returned to normal or near-normal levels. However, the monkeys appeared to have suffered a permanent hearing loss throughout most of their hearing range, especially in the midfrequency range, where they are normally most sensitive. A review of the animal literature reveals little support for the previous view that bilateral auditory cortex lesions have little or no effect on absolute sensitivity in primates and carnivores. Most previous studies did not conduct detailed hearing tests, and those that did often noted a hearing loss. The hearing loss found in monkeys is similar to that noted in human cases following bilateral auditory cortex lesions. The current findings thus provide experimental verification of the clinical phenomenon of cortical deafness.
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Marshall, J. Wb, K. J. Duffin, A. R. Green, and R. M. Ridley. "NXY-059, the free radical trapping nitrone-based agent, reduces hemiparesis and reduces grey and white matter damage after focal cerebral ischemia in monkeys." Stroke 32, suppl_1 (January 2001): 327. http://dx.doi.org/10.1161/str.32.suppl_1.327.
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60 There is little published evidence for protection of white matter with neuroprotective drugs in animal models of stroke, yet white matter protection may be important in achieving clinical efficacy. We have examined the effects of NXY-059, a nitrone-based free radical trapping agent, on long-term functional disability in a primate model of stroke. We also examined histopathological effects, including analyses of grey and white matter damage. Five minutes after unilateral permanent middle cerebral artery occlusion, marmosets received a 1 ml i.v. infusion of saline (n=5) or NXY-059 (28 mg/kg) (n=6) and osmotic minipumps (model 2001D) were implanted s.c. to provide continuous drug or saline infusion for 48 h. Drug-filled pumps released NXY-059 at a rate of approximately 16 mg/kg/h. The plasma unbound drug concentration at 24 h was 76.3 ± 5.7 μM, a level well tolerated in acute stroke patients. The monkeys had been trained and tested on a variety of behavioral tasks before surgery. NXY-059-treated monkeys were significantly better at reaching with their contralesional arm than were saline-treated monkeys when re-tested 3 (p<0.01) and 10 weeks (p<0.01) after surgery. NXY-059-treatment also significantly reduced spatial neglect measured 3 weeks after surgery (p<0.01) compared with the saline group. After behavioral testing was complete, histopathological analysis showed NXY-059-treated monkeys had significantly smaller infarcts than saline-treated monkeys (F (1, 10)=5.21, p<0.05). NXY-059 reduced overall infarct size by 51%, damage to the cortex was reduced by 54%, white matter by 52%, caudate by 49%, and putamen by 33% compared with saline-treated monkeys. In conclusion, NXY-059 substantially lessened the functional disability in these monkeys. This drug protects not only cortical tissue, but also white matter and subcortical structures against ischemic damage. Together these findings bode well for advancing this drug to further clinical trials for its use in acute stroke.
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O'Shea, Jacinta, Neil G. Muggleton, Alan Cowey, and Vincent Walsh. "Timing of Target Discrimination in Human Frontal Eye Fields." Journal of Cognitive Neuroscience 16, no. 6 (July 2004): 1060–67. http://dx.doi.org/10.1162/0898929041502634.
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Frontal eye field (FEF) neurons discharge in response to behaviorally relevant stimuli that are potential targets for saccades. Distinct visual and motor processes have been dissociated in the FEF of macaque monkeys, but little is known about the visual processing capacity of FEF in humans. We used double-pulse transcranial magnetic stimulation [(d)TMS] to investigate the timing of target discrimination during visual conjunction search. We applied dual TMS pulses separated by 40 msec over the right FEF and vertex. These were applied in five timing conditions to sample separate time windows within the first 200 msec of visual processing. (d)TMS impaired search performance, reflected in reduced d′ scores. This effect was limited to a time window between 40 and 80 msec after search array onset. These parameters correspond with single-cell activity in FEF that predicts monkeys' behavioral reports on hit, miss, false alarm, and correct rejection trials. Our findings demonstrate a crucial early role for human FEF in visual target discrimination that is independent of saccade programming.
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Addou, Touria, Nedialko I. Krouchev, and John F. Kalaska. "Motor cortex single-neuron and population contributions to compensation for multiple dynamic force fields." Journal of Neurophysiology 113, no. 2 (January 15, 2015): 487–508. http://dx.doi.org/10.1152/jn.00094.2014.
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To elucidate how primary motor cortex (M1) neurons contribute to the performance of a broad range of different and even incompatible motor skills, we trained two monkeys to perform single-degree-of-freedom elbow flexion/extension movements that could be perturbed by a variety of externally generated force fields. Fields were presented in a pseudorandom sequence of trial blocks. Different computer monitor background colors signaled the nature of the force field throughout each block. There were five different force fields: null field without perturbing torque, assistive and resistive viscous fields proportional to velocity, a resistive elastic force field proportional to position and a resistive viscoelastic field that was the linear combination of the resistive viscous and elastic force fields. After the monkeys were extensively trained in the five field conditions, neural recordings were subsequently made in M1 contralateral to the trained arm. Many caudal M1 neurons altered their activity systematically across most or all of the force fields in a manner that was appropriate to contribute to the compensation for each of the fields. The net activity of the entire sample population likewise provided a predictive signal about the differences in the time course of the external forces encountered during the movements across all force conditions. The neurons showed a broad range of sensitivities to the different fields, and there was little evidence of a modular structure by which subsets of M1 neurons were preferentially activated during movements in specific fields or combinations of fields.
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Schwarz, D. W., and R. W. Tomlinson. "Spectral response patterns of auditory cortex neurons to harmonic complex tones in alert monkey (Macaca mulatta)." Journal of Neurophysiology 64, no. 1 (July 1, 1990): 282–98. http://dx.doi.org/10.1152/jn.1990.64.1.282.
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1. The auditory cortex in the superior temporal region of the alert rhesus monkey was explored for neuronal responses to pure and harmonic complex tones and noise. The monkeys had been previously trained to recognize the similarity between harmonic complex tones with and without fundamentals. Because this suggested that they could preceive the pitch of the lacking fundamental similarly to humans, we searched for neuronal responses relevant to this perception. 2. Combination-sensitive neurons that might explain pitch perception were not found in the surveyed cortical regions. Such neurons would exhibit similar responses to stimuli with similar periodicities but differing spectral compositions. The fact that no neuron with responses to a fundamental frequency responded also to a corresponding harmonic complex missing the fundamental indicates that cochlear distortion products at the fundamental may not have been responsible for missing fundamental-pitch perception in these monkeys. 3. Neuronal responses can be expressed as relatively simple filter functions. Neurons with excitatory response areas (tuning curves) displayed various inhibitory sidebands at lower and/or higher frequencies. Thus responses varied along a continuum of combined excitatory and inhibitory filter functions. 4. Five elementary response classes along this continuum are presented to illustrate the range of response patterns. 5. “Filter (F) neurons” had little or no inhibitory sidebands and responded well when any component of a complex tone entered its pure-tone receptive field. Bandwidths increased with intensity. Filter functions of these neurons were thus similar to cochlear nerve-fiber tuning curves. 6. ”High-resolution filter (HRF) neurons” displayed narrow tuning curves with narrowband widths that displayed little growth with intensity. Such cells were able to resolve up to the lowest seven components of harmonic complex tones as distinct responses. They also responded well to wideband stimuli. 7. “Fundamental (F0) neurons” displayed similar tuning bandwidths for pure tones and corresponding fundamentals of harmonic complexes. This response pattern was due to lower harmonic complexes. This response pattern was due to lower inhibitory sidebands. Thus these cells cannot respond to missing fundamentals of harmonic complexes. Only physically present components in the pure-tone receptive field would excite such neurons. 8. Cells with no or very weak responses to pure tones or other narrowband stimuli responded well to harmonic complexes or wideband noise.(ABSTRACT TRUNCATED AT 400 WORDS)
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Hodgson, J. A., S. Wichayanuparp, M. R. Recktenwald, R. R. Roy, G. McCall, M. K. Day, D. Washburn, J. W. Fanton, I. Kozlovskaya, and V. R. Edgerton. "Circadian Force and EMG Activity in Hindlimb Muscles of Rhesus Monkeys." Journal of Neurophysiology 86, no. 3 (September 1, 2001): 1430–44. http://dx.doi.org/10.1152/jn.2001.86.3.1430.
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Continuous intramuscular electromyograms (EMGs) were recorded from the soleus (Sol), medial gastrocnemius (MG), tibialis anterior (TA), and vastus lateralis (VL) muscles of Rhesus during normal cage activity throughout 24-h periods and also during treadmill locomotion. Daily levels of MG tendon force and EMG activity were obtained from five monkeys with partial datasets from three other animals. Activity levels correlated with the light-dark cycle with peak activities in most muscles occurring between 08:00 and 10:00. The lowest levels of activity generally occurred between 22:00 and 02:00. Daily EMG integrals ranged from 19 mV/s in one TA muscle to 3339 mV/s in one Sol muscle: average values were 1245 (Sol), 90 (MG), 65 (TA), and 209 (VL) mV/s. The average Sol EMG amplitude per 24-h period was 14 μV, compared with 246 μV for a short burst of locomotion. Mean EMG amplitudes for the Sol, MG, TA, and VL during active periods were 102, 18, 20, and 33 μV, respectively. EMG amplitudes that approximated recruitment of all fibers within a muscle occurred for 5–40 s/day in all muscles. The duration of daily activation was greatest in the Sol [151 ± 45 (SE) min] and shortest in the TA (61 ± 19 min). The results show that even a “postural” muscle such as the Sol was active for only ∼9% of the day, whereas less active muscles were active for ∼4% of the day. MG tendon forces were generally very low, consistent with the MG EMG data but occasionally reached levels close to estimates of the maximum force generating potential of the muscle. The Sol and TA activities were mutually exclusive, except at very low levels, suggesting very little coactivation of these antagonistic muscles. In contrast, the MG activity usually accompanied Sol activity suggesting that the MG was rarely used in the absence of Sol activation. The results clearly demonstrate a wide range of activation levels among muscles of the same animal as well as among different animals during normal cage activity.
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Schoof, Valérie A. M., and Katharine M. Jack. "Male social bonds: strength and quality among co-resident white-faced capuchin monkeys (Cebus capucinus)." Behaviour 151, no. 7 (2014): 963–92. http://dx.doi.org/10.1163/1568539x-00003179.
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Social relationships among immigrant same-sex co-residents have received relatively little attention, particularly for species where males are the dispersing sex. White-faced capuchins (Cebus capucinus) are unusual in that immigrant males form cooperative alliances with co-resident males during intergroup encounters, and also have affiliative and tolerant intragroup relationships. We collected approx. 3341 h of focal animal data on 25 adult and subadult males in five groups of wild Cebus capucinus in the Santa Rosa Sector, Costa Rica, across three distinct field seasons. Using generalized linear mixed models, we examined the influence of number of co-resident males, group socionomic sex ratio, dominance status and age, and past parallel dispersal on social bond strength (i.e., proximity, contact rest, grooming, preferred grooming partners) and quality (i.e., grooming reciprocity) for 47 unique male–male dyads. Overall, dyads that included an alpha male had the weakest and least equitable bonds, while dyads composed of subordinate males had the strongest and most equitable bonds, with subordinate subadult peers being most likely to form preferred relationships. Several measures of bond strength and quality were highest among dyads in groups with few males and low socionomic sex (female-to-male) ratios. Dyad partners who had previously engaged in parallel dispersal had slightly better bonds than those that did not, suggesting that kinship and/or familiarity may be important. Our results indicate that within groups, male relationships are influenced by power asymmetry, partner availability, and dyad relationship history.
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Winkle, Laura S. Van, Michelle V. Fanucchi, Lisa A. Miller, Gregory L. Baker, Laurel J. Gershwin, Edward S. Schelegle, Dallas M. Hyde, Michael J. Evans, and Charles G. Plopper. "Epithelial cell distribution and abundance in rhesus monkey airways during postnatal lung growth and development." Journal of Applied Physiology 97, no. 6 (December 2004): 2355–63. http://dx.doi.org/10.1152/japplphysiol.00470.2004.
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Lung development is both a pre- and postnatal process. Although many lung diseases have their origins in early childhood, few quantitative data are available on the normal growth and differentiation of both the conducting airways and the airway epithelium during the postnatal period. We examined rhesus monkey lungs from five postnatal ages: 4–6 days and 1, 2, 3, and 6 mo. Airways increase significantly in both length and circumference as monkeys increase significantly in body weight from 5 days to 6 mo. In this study we asked: as basement membrane surface area increases, does the epithelial cell organization change? To answer this question, we quantified total epithelial cell mass using high-resolution light micrographs and morphometric techniques on sections from defined airway regions: trachea, proximal intrapulmonary bronchus (generations 1 or 2), and distal intrapulmonary bronchus (generations 6–8). Epithelial thickness decreased in the smaller, more distal, airways compared with trachea but did not change with age in the trachea and proximal bronchus. The volume fraction of all cell types measured did not change significantly. Ciliated cells in the distal bronchus and goblet cells in the trachea both decreased in abundance with increasing age. Overall, the epithelial cell populations changed little in terms of mass or relative abundance to each other during this period of active postnatal lung growth. Regarding the proximal conducting airway epithelium, we conclude that 1) the steady-state abundance is tightly regulated to keep the proportion of cell types constant, and 2) establishment of these cell types occurs before 4–6 days postnatal age. We conclude that growth of the proximal airways occurs primarily in length and lags behind that of the lung parenchyma.
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Levitt, Jonathan B., Robert A. Schumer, S. Murray Sherman, Peter D. Spear, and J. Anthony Movshon. "Visual Response Properties of Neurons in the LGN of Normally Reared and Visually Deprived Macaque Monkeys." Journal of Neurophysiology 85, no. 5 (May 1, 2001): 2111–29. http://dx.doi.org/10.1152/jn.2001.85.5.2111.
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It is now well appreciated that parallel retino-geniculo-cortical pathways exist in the monkey as in the cat, the species in which parallel visual pathways were first and most thoroughly documented. What remains unclear is precisely how many separate pathways pass through the parvo- and magnocellular divisions of the macaque lateral geniculate nucleus (LGN), what relationships—homologous or otherwise—these pathways have to the cat's X, Y, and W pathways, and whether these are affected by visual deprivation. To address these issues of classification and trans-species comparison, we used achromatic stimuli to obtain an extensive set of quantitative measurements of receptive field properties in the parvo- and magnocellular laminae of the LGN of nine macaque monkeys: four normally reared and five monocularly deprived of vision by lid suture near the time of birth. In agreement with previous studies, we find that on average magnocellular neurons differ from parvocellular neurons by having shorter response latencies to optic chiasm stimulation, greater sensitivity to luminance contrast, and better temporal resolution. Magnocellular laminae are also distinguished by containing neurons that summate luminance over their receptive fields nonlinearly (Y cells) and whose temporal response phases decrease with increasing stimulus contrast (indicative of a contrast gain control mechanism). We found little evidence for major differences between magno- and parvocellular neurons on the basis of most spatial parameters except that at any eccentricity, the neurons with the smallest receptive field centers tended to be parvocellular. All parameters were distributed unimodally and continuously through the parvo- and magnocellular populations, giving no indications of subpopulations within each division. Monocular deprivation led to clear anatomical effects: cells in deprived-eye laminae were pale and shrunken compared with those in nondeprived eye laminae, and Cat-301 immunoreactivity in deprived laminae was essentially uniformly abolished. However, deprivation had only subtle effects on the response properties of LGN neurons. Neurons driven by the deprived eye in both magno- and parvocellular laminae had lower nonlinearity indices (i.e., summed signals across their receptive fields more linearly) and were somewhat less responsive. In magnocellular laminae driven by the deprived eye, neuronal response latencies to stimulation of the optic chiasm were slightly shorter than those in the nondeprived laminae, and receptive field surrounds were a bit stronger. No other response parameters were affected by deprivation, and there was no evidence for loss of a specific cell class as in the cat.
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Nakayama, Eri, Ayaka Yokoyama, Hiroko Miyamoto, Manabu Igarashi, Noriko Kishida, Keita Matsuno, Andrea Marzi, et al. "Enzyme-Linked Immunosorbent Assay for Detection of Filovirus Species-Specific Antibodies." Clinical and Vaccine Immunology 17, no. 11 (September 22, 2010): 1723–28. http://dx.doi.org/10.1128/cvi.00170-10.
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ABSTRACT Several enzyme-linked immunosorbent assays (ELISAs) for the detection of filovirus-specific antibodies have been developed. However, diagnostic methods to distinguish antibodies specific to the respective species of filoviruses, which provide the basis for serological classification, are not readily available. We established an ELISA using His-tagged secreted forms of the transmembrane glycoproteins (GPs) of five different Ebola virus (EBOV) species and one Marburg virus (MARV) strain as antigens for the detection of filovirus species-specific antibodies. The GP-based ELISA was evaluated by testing antisera collected from mice immunized with virus-like particles as well as from humans and nonhuman primates infected with EBOV or MARV. In our ELISA, little cross-reactivity of IgG antibodies was observed in most of the mouse antisera. Although sera and plasma from some patients and monkeys showed notable cross-reactivity with the GPs from multiple filovirus species, the highest reactions of IgG were uniformly detected against the GP antigen homologous to the virus species that infected individuals. We further confirmed that MARV-specific IgM antibodies were specifically detected in specimens collected from patients during the acute phase of infection. These results demonstrate the usefulness of our ELISA for diagnostics as well as ecological and serosurvey studies.
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Optican, L. M., and F. A. Miles. "Visually induced adaptive changes in primate saccadic oculomotor control signals." Journal of Neurophysiology 54, no. 4 (October 1, 1985): 940–58. http://dx.doi.org/10.1152/jn.1985.54.4.940.
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Saccades are the rapid eye movements used to change visual fixation. Normal saccades end abruptly with very little postsaccadic ocular drift, but acute ocular motor deficits can cause the eyes to drift appreciably after a saccade. Previous studies in both patients and monkeys with peripheral ocular motor deficits have demonstrated that the brain can suppress such postsaccadic drifts. Ocular drift might be suppressed in response to visual and/or proprioceptive feedback of position and/or velocity errors. This study attempts to characterize the adaptive mechanism for suppression of postsaccadic drift. The responses of seven rhesus monkeys were studied to postsaccadic retinal slip induced by horizontal exponential movements of a full-field stimulus. After several hours of saccade-related retinal image slip, the eye movements of the monkeys developed a zero-latency, compensatory postsaccadic ocular drift. This ocular drift was still evident in the dark, although smaller (typically 15% of the amplitude of the antecedent saccade, up to a maximum drift of 8 degrees). Retinal slip alone, without a net displacement of the image, was sufficient to elicit these adaptive changes, and compensation for leftward and rightward saccades was independent. It took several days to complete adaptation, but recovery (in the light) was much quicker. The decay of this adaptation in darkness was very slow; after 3 days the ocular drift was reduced by less than 50%. The time constants of single exponential curve fits to adaptation time courses of data from five animals were 35 h for acquisition, 4 h for recovery, and at least 40 h for decay in darkness. Descriptions of the central innervation for a saccade are usually simplified to only two components: a pulse and a step. It has been hypothesized that suppression of pathological postsaccadic drift is achieved by adjusting the ratio of the pulse to the step of innervation (19, 26). However, we show that the time constant of the ocular drift is influenced by the time constant of the adapting stimulus, which cannot be explained by the simple pulse-step model of saccadic innervation. A more realistic representation of the saccadic innervation has three components: a pulse, an exponential slide, and a step. Normal saccades were accurately simulated by a fourth-order, linear model of the ocular motor plant driven by such a pulse-slide-step combination. Saccades made after prolonged exposure to optically induced retinal image slip could also be simulated by properly adjusting the slide and step components.(ABSTRACT TRUNCATED AT 400 WORDS)
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Warren, S., H. A. Hamalainen, and E. P. Gardner. "Objective classification of motion- and direction-sensitive neurons in primary somatosensory cortex of awake monkeys." Journal of Neurophysiology 56, no. 3 (September 1, 1986): 598–622. http://dx.doi.org/10.1152/jn.1986.56.3.598.
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In order to classify movement-sensitive neurons in SI cortex, and to estimate their relative distribution, we have developed a new simple method for controlled motion of textured surfaces across the skin, as well as a set of objective criteria for determining direction selectivity. Moving stimuli were generated using 5 mm thick precision gear wheels, whose teeth formed a grafting. They were mounted on the shafts of low-torque potentiometers (to measure the speed and direction of movement) and rolled manually across the skin using the potentiometer shaft as an axle. As the grafting wheel was advanced, its ridges sequentially contacted a specific set of points on the skin, leaving gaps of defined spacing that were unstimulated. This stimulus was reproducible from trial to trial and produced little distention of the skin. Three objective criteria were used to categorize responses: the ratio of responses to motion in the most and least preferred directions [direction index (DI)], the difference between mean firing rates in the two directions divided by the average standard deviation [index of discriminability (delta'e)], and statistical tests. Neurons were classified as direction sensitive if DI greater than 35, delta's greater than or equal to 1.35 (equivalent to 75% correct discrimination by an unbiased observer), and firing rates in most- and least-preferred directions were significantly different (P less than 0.05). Good agreement was found between the three classification schemes. Recordings were made from 1,020 cortical neurons in the hand and forearm regions of primary somatosensory cortex (areas 3b, 1 and 2) of five macaque monkeys. Tangential motion across the skin was found to be an extremely effective stimulus for SI cortical neurons. Two hundred eighty six of 757 tactile neurons (38%) responded more vigorously to moving stimuli than to pressure or tapping the skin. One hundred twenty-one cells were tested with moving gratings and were classified according to their ability to differentiate movement in longitudinal and transverse directions. Responses to the moving gratings resembled those observed when stroking the skin with brushed, edges, or blunt probes. Three major types of firing patterns were found: motion sensitive, direction sensitive, and orientation sensitive. Motion-sensitive neurons (37%) responded to movement in both longitudinal and transverse directions with only slight difference in firing rates and interval distributions. Responses throughout the field were fairly uniform, and no clear point of maximum sensitivity was apparent. Direction-sensitive neurons (60%) displayed clear preferences for movement in one or more directions.4
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HEGDÉ, JAY, and DAVID C. VAN ESSEN. "Strategies of shape representation in macaque visual area V2." Visual Neuroscience 20, no. 3 (May 2003): 313–28. http://dx.doi.org/10.1017/s0952523803203102.
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Contours and surface textures provide powerful cues used in image segmentation and the analysis of object shape. To learn more about how the visual system extracts and represents these visual cues, we studied the responses of V2 neurons in awake, fixating monkeys to complex contour stimuli (angles, intersections, arcs, and circles) and texture patterns such as non-Cartesian gratings, along with conventional bars and sinusoidal gratings. Substantial proportions of V2 cells conveyed information about many contour and texture characteristics associated with our stimuli, including shape, size, orientation, and spatial frequency. However, the cells differed considerably in terms of their degree of selectivity for the various stimulus characteristics. On average, V2 cells responded better to grating stimuli but were more selective for contour stimuli. Metric multidimensional scaling and principal components analysis showed that, as a population, V2 cells show strong correlations in how they respond to different stimulus types. The first two and five principal components accounted for 69% and 85% of the overall response variation, respectively, suggesting that the response correlations simplified the population representation of shape information with relatively little loss of information. Moreover, smaller random subsets of the population carried response correlation patterns very similar to the population as a whole, indicating that the response correlations were a widespread property of V2 cells. Thus, V2 cells extract information about a number of higher order shape cues related to contours and surface textures and about similarities among many of these shape cues. This may reflect an efficient strategy of representing cues for image segmentation and object shape using finite neuronal resources.
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Gochin, P. M., M. Colombo, G. A. Dorfman, G. L. Gerstein, and C. G. Gross. "Neural ensemble coding in inferior temporal cortex." Journal of Neurophysiology 71, no. 6 (June 1, 1994): 2325–37. http://dx.doi.org/10.1152/jn.1994.71.6.2325.
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1. Isolated, single-neuron extracellular potentials were recorded sequentially in area TE of the inferior temporal cortex (IT) of two macaque monkeys (n = 58 and n = 41 neurons). Data were obtained while the animals were performing a paired-associate task. The task utilized five stimuli and eight stimulus pairings (4 correct and 4 incorrect). Data were evaluated as average spike rate during experimental epochs of 100 or 400 ms. Single-unit and population characteristics were measured using a form of linear discriminant analysis and information theoretic measures. To evaluate the significance of covariance on population code measures, additional data consisting of simultaneous recordings from < or = 8 isolated neurons (n = 37) were obtained from a third macaque monkey that was passively viewing visual stimuli. 2. On average, 43% of IT neurons were activated by any of the stimuli used (60% if those inhibited also are included). Yet the neurons were rather unique in the relative magnitude of their responses to each stimulus in the test set. These results suggest that information may be represented in IT by the pattern of activity across neurons and that the representation is not sparsely coded. It is further suggested that the representation scheme may have similarities to DNA or computer codes wherein a coding element is not a local parametric descriptor. This is a departure from the V1 representation, which appears to be both local and parametric. It is also different from theories of IT representation that suggest a constructive basis set or “alphabet”. From this view, determination of stimulus discrimination capacity in IT should be evaluated by measures of population activity patterns. 3. Evaluation of small groups of simultaneously recorded neurons obtained during a fixation task suggests that little information about visual stimuli is conveyed by covariance of activity in IT when a 100-ms time scale is used as in this study. This finding is consistent with a prior report, by Gochin et al., which used a 1-ms time scale and failed to find neural activity coherence or oscillations dependent on stimuli. 4. Population-stimulus-discrimination capacity measures were influenced by the number of neurons and to some extent the number and type of stimuli. 5. Information conveyed by individual neurons (mutual information) averaged 0.26 bits. The distribution of information values was unimodal and is therefore more consistent with a distributed than a local coding scheme.(ABSTRACT TRUNCATED AT 400 WORDS)
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Fu, Q. G., J. I. Suarez, and T. J. Ebner. "Neuronal specification of direction and distance during reaching movements in the superior precentral premotor area and primary motor cortex of monkeys." Journal of Neurophysiology 70, no. 5 (November 1, 1993): 2097–116. http://dx.doi.org/10.1152/jn.1993.70.5.2097.
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1. Single-unit neuronal activity was recorded in the primary motor and superior precentral premotor areas of two rhesus monkeys during an arm reaching task. The task involved moving a cursor displayed on a video terminal using a draftsman's arm-type manipulandum. From a centrally located start box the animal was required to move to 1 of 48 target boxes at eight different directions (0-360 degrees in 45 degrees intervals) and six distances (1.4-5.4 cm in 0.8-cm increments). Both direction and distance for the upcoming movement were unpredictable. 2. The activity of 197 arm movement-related cells was recorded and evaluated for each of the 48 targets. Histological examination showed the cells to be primarily in the primary motor cortex or in the premotor area around the superior precentral sulcus. Each cell's discharge was aligned on movement onset and averaged over five trials for each target. Movement kinematics including hand path velocity were also determined. The task time was divided into three epochs, a premovement period (PT), a movement period (MT), and total time (TT = PT+MT). For each epoch the average firing was correlated with the direction and distance of the movement using various regression procedures. 3. An analysis of variance (ANOVA) showed that the majority of neurons were modulated significantly by movement direction in each of the three time periods, PT (73.7%), MT (68.3%), and TT (78.5%). The relationship of the firing to direction was fit to a cosine tuning function for each significantly modulated cell. In 86.3% of the cells the firing was correlated significantly with a cosine function of movement direction in TT. A cell's preferred direction varied little for different movement distances. The mean difference in preferred direction for the smallest possible change in distance (0.8 cm) was 12.8 +/- 11.4 degrees (SD) and 17.1 +/- 14.7 degrees for the largest change in distance (4.0 cm). 4. Correlation analysis revealed that the activity of the majority of cells was modulated significantly by distance along at least one direction in each of the three time periods, PT (46.8%), MT (68.8%), and TT (67.7%). Subsequently, a univariate linear regression model was used to quantify a cell's discharge as a function of distance. For the regressions of firing with distance with a statistically significant correlation (r > 0.8), the mean slope was 3.59 +/- 0.17 spikes.s-1.cm-1 for the total time. The existence of a significant distance modulation was not invariably correlated with a cell's preferred movement direction.(ABSTRACT TRUNCATED AT 400 WORDS)
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Smith, Angela R., Hennessy Jane, Heisel Kurth Margaret, and Nelson C. Stephen. "Reversible Bony Changes after Treatment with Bevacizumab in a Child with Cutaneovisceral Angiomatosis with Thrombocytopenia Syndrome: A Case Report and Review of the Literature." Blood 110, no. 11 (November 16, 2007): 1323. http://dx.doi.org/10.1182/blood.v110.11.1323.1323.
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Abstract Cutaneovisceral Angiomatosis with Thrombocytopenia (CAT) syndrome is a rare vascular disorder involving the skin and gastrointestinal tract. Clinical features of CAT syndrome include multiple, discrete skin lesions, gastrointestinal bleeding and thrombocytopenia. CAT syndrome is typically treated with angiogenesis inhibitors like corticosteroids and vincristine. Bevacizumab is a relatively new antiangiogenic agent that is FDA approved as a first-line agent for metastatic carcinoma of the colon or rectum in combination with a 5-FU based regimen. Bevacizumab is a humanized monoclonal antibody that binds all five isoforms of human vascular endothelial growth factor (VEGF) and prevents its interaction with the VEGF receptor. There is currently very little clinical pediatric experience with antiangiogenic agents. Case: Though subtly symptomatic from birth, our patient was diagnosed with CAT syndrome at four months of age after an episode of grossly bloody stools. After failed therapy with corticosteroids and vincristine, the patient was given bevacizumab 10mg/kg/dose every two weeks for four doses with excellent clinical response. After her fourth dose, a chest radiograph revealed incidental, asymptomatic metaphyseal lesions of the humeri. A complete bone survey revealed similar lesions in the metaphyses of nearly all of her long bones. (Figure 1) Given preclinical data suggesting these lesions could result from the use of VEGF inhibitors, bevacizumab was discontinued. All metaphyseal lesions subsequently resolved. (Figure 2) To our knowledge, this is the first report of bony toxicity in a human receiving bevacizumab. A thorough literature review on VEGF inhibitors revealed no reported cases of metaphyseal lesions or stunted growth in humans receiving VEGF inhibitors. Animal studies, however, suggest this may be possible. Growth plates consist of avascular cartilage that is eventually replaced by bone. This process requires invasion of the cartilage with metaphyseal blood vessels and has been shown to be directed by a VEGF gradient (Nature Medicine1999; 5(6): 623–628). Preclinical studies performed using VEGF inhibitors in monkeys demonstrated reversible physeal dysplasia of the distal femur in the monkeys with open growth plates (Toxicol Pathol, 1999; 27(1): 78–86). We hypothesize that use of the VEGF inhibitor, bevacizumab, in a small child with active epiphyseal growth plates caused the radiographic lesions we observed. It appears that this side effect is reversible, at least after short-term use. We propose that close monitoring for bony toxicity is required for all children receiving bevacizumab and that this drug should be used only with caution in children with active bone growth. Figure Figure Figure Figure
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Kamischke, A., M. Kuhlmann, GF Weinbauer, M. Luetjens, CH Yeung, HL Kronholz, and E. Nieschlag. "Gonadal protection from radiation by GnRH antagonist or recombinant human FSH: a controlled trial in a male nonhuman primate (Macaca fascicularis)." Journal of Endocrinology 179, no. 2 (November 1, 2003): 183–94. http://dx.doi.org/10.1677/joe.0.1790183.
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Chemotherapy and radiation often damage spermatogenesis irreversibly in oncological patients and various approaches to gonadal protection have been tested with equivocal results. In rats, hormonal protection of spermatogenesis can be achieved by blocking gonadotropin secretion. However, whether the same mechanisms can effect gonadal protection in primates remains questionable. To clarify this Issue we conducted a placebo-controlled trial in a preclinical animal model using macaques (Macaca fascicularis). Twenty adult male monkeys (five in each group) were randomized to receive either recombinant human FSH, GnRH antagonist or saline injections (two groups) for 36 days. On day 29 all groups except one saline-treated control group were exposed to a single testicular irradiation of 4 Gy. Every 2 weeks before, during and after the treatment, ejaculates, body weight, testicular Volume and hormones were analyzed until day 539. In addition, repeated testicular biopsies were performed. Testicular Volume and inhibin B decreased significantly in all irradiated groups compared with baseline and with the non-irradiated control group, followed by a gradual recovery of these parameters, which was, especially at the earlier time points, significantly better in the FSH-treated group compared with both other irradiated groups. Irradiation caused a drastic decrease of sperm parameters in all groups, followed by a partial recovery of sperm parameters, which was significantly slower in the early phases of recovery in the GnRH antagonist group compared with the vehicle group. Testicular histology showed a significant depletion on study day 261 in all irradiated animals. In conclusion, in clear contrast to rodent studies, GnRH antagonist treatment did not provide gonadal protection in this primate model. FSH treatment resulted in slightly better recovery of spermatogenesis, which appears to be of no or only little clinical relevance.
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Deyoe, Edgar A., Thomas C. Trusk, and Margaret T. T. Wong-Riley. "Activity correlates of cytochrome oxidase-defined compartments in granular and supragranular layers of primary visual cortex of the macaque monkey." Visual Neuroscience 12, no. 4 (July 1995): 629–39. http://dx.doi.org/10.1017/s0952523800008920.
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AbstractTo determine if changes in metabolic capacity revealed by cytochrome oxidase (CO) histochemistry are related to sustained changes in energy-utilizing neuronal activity, we assayed CO levels and recorded multiunit firing rates along nearly tangential penetrations of V1 in seven adult macaque monkeys before and after single, monocular injections of TTX. Within as little as 14 h, TTX blockade began to reduce CO staining in zones of layer 4C that received dominant input from the injected eye. Since simple monocular occlusion has only minor effects on cortical CO levels (Trusk et al., 1990), the changes in activity that were specifically associated with CO depletion were isolated by comparing spike rates during monocular TTX blockade and during monocular occlusion. Five second samples of multiunit spike rate were obtained after 2-min adaptation to each of four adapting fields: black, gray, white, and textured. Results were similar for these four conditions. In layer 4C, ocular dominance zones with input from the TTX eye had ongoing spike rates that were 48% of the rates in zones with input from a normal but occluded eye. In six animals, it was possible to record activity at a single site before, during, and after the onset of TTX blockade. Background activity at these interpuff sites decreased as much as 3-fold in less than 1 h but stabilized within 3–4 h to an average of 53% of pre-TTX rates. These data support the interpretation that energy utilization linked to sustained spike rates partially regulates CO levels under normal conditions, at least in layer 4. Furthermore, changes in neuronal activity induced by retinal TTX preceded the detectable reduction in CO activity in V1 suggesting that the adjustment of CO levels was in response to the altered activity.
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Amador, Nelly, Madeleine Schlag-Rey, and John Schlag. "Reward-Predicting and Reward-Detecting Neuronal Activity in the Primate Supplementary Eye Field." Journal of Neurophysiology 84, no. 4 (October 1, 2000): 2166–70. http://dx.doi.org/10.1152/jn.2000.84.4.2166.
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In addition to cells specifically active with visual stimuli, saccades, or fixation, the supplementary eye field contains cells that fire in precise temporal relationship with the occurrence of reward. We studied reward-related activity in two monkeys performing a prosaccade/antisaccade task and in one monkey trained in memory prosaccades only. Two types of neurons were distinguished by their reciprocal firing pattern: reward-predicting (RP) and reward-detecting (RD). RP neurons linearly increased their firing as early as 150 ms before saccade onset until the occurrence of reward, at which time they abruptly ceased firing. In contrast, RD neurons fired in phase with reward delivery, even when its duration was varied and when it was repeated at different frequencies. RD discharges were little affected or unaffected by the position of a visual cue that briefly anchored the goal at the onset of reward. The complementary firing patterns of the RP and RD neurons could provide a feedback mechanism necessary for learning and performing the task.
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Park, Min Young, Bala Murali Krishna Vasamsetti, Wan Seop Kim, Hee Jung Kang, Do-Young Kim, Byeonghwi Lim, Kahee Cho, et al. "Comprehensive Analysis of Cardiac Xeno-Graft Unveils Rejection Mechanisms." International Journal of Molecular Sciences 22, no. 2 (January 13, 2021): 751. http://dx.doi.org/10.3390/ijms22020751.
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Porcine heart xenotransplantation is a potential treatment for patients with end-stage heart failure. To understand molecular mechanisms of graft rejection after heart transplantation, we transplanted a 31-day-old alpha-1,3-galactosyltransferase knockout (GTKO) porcine heart to a five-year-old cynomolgus monkey. Histological and transcriptome analyses were conducted on xenografted cardiac tissue at rejection (nine days after transplantation). The recipient monkey’s blood parameters were analyzed on days −7, −3, 1, 4, and 7. Validation was conducted by quantitative real-time PCR (qPCR) with selected genes. A non-transplanted GTKO porcine heart from an age-matched litter was used as a control. The recipient monkey showed systemic inflammatory responses, and the rejected cardiac graft indicated myocardial infarction and cardiac fibrosis. The transplanted heart exhibited a total of 3748 differentially expressed genes compared to the non-transplanted heart transcriptome, with 2443 upregulated and 1305 downregulated genes. Key biological pathways involved at the terminal stage of graft rejection were cardiomyopathies, extracellular interactions, and ion channel activities. The results of qPCR evaluation were in agreement with the transcriptome data. Transcriptome analysis of porcine cardiac tissue at graft rejection reveals dysregulation of the key molecules and signaling pathways, which play relevant roles on structural and functional integrities of the heart.
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Borgeaud, Christèle, Alessandra Schnider, Michael Krützen, and Redouan Bshary. "Female vervet monkeys fine-tune decisions on tolerance versus conflict in a communication network." Proceedings of the Royal Society B: Biological Sciences 284, no. 1867 (November 15, 2017): 20171922. http://dx.doi.org/10.1098/rspb.2017.1922.
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Group living promotes opportunities for both cooperation and competition. Selection on the ability to cope with such opposing social opportunities has been proposed as a driving force in the evolution of large brains in primates and other social species. However, we still know little about the degree of complexity involved in such social strategies. Here, we report advanced social strategies in wild vervet monkeys. Building on recent experimental evidence that subordinate females trade grooming for tolerance from higher-ranking individuals during foraging activities, we show that the audience composition strongly affects this trade. First, tolerance was lower if the audience contained individuals that outranked the subordinate partner, independently of audience size and kinship relationships. Second, we found a significant interaction between previous grooming and relative rank of bystanders: dominant subjects valued recent grooming by subordinates while intermediate ranked subjects valued the option to aggress subordinate partners in the presence of a dominant audience. Aggressors were also more likely to emit coalition recruitment calls if the audience contained individuals that outranked the subordinate partner. In conclusion, vervet monkeys include both recent grooming and knowledge about third-party relationships to make complex decisions when trading grooming for tolerance, leading to a finely balanced trade-off between reciprocation and opportunities to reinforce rank relationships.
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Zhang, D. X., C. M. Owens, and W. D. Willis. "Two forms of inhibition of spinothalamic tract neurons produced by stimulation of the periaqueductal gray and the cerebral cortex." Journal of Neurophysiology 65, no. 6 (June 1, 1991): 1567–79. http://dx.doi.org/10.1152/jn.1991.65.6.1567.
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1. Recordings were made from the lumbosacral spinal cord in anesthetized macaque monkeys. The inhibitory effects of electrical stimulation of the periaqueductal gray (PAG) and the cerebral cortex or cerebral peduncle (CP) were tested and compared by recording 1) cord dorsum potentials evoked by stimulation of the sural nerve, 2) discharges recorded extracellularly, and 3) membrane potentials recorded intracellularly from spinothalamic tract (STT) neurons at rest (background activity) or in response to stimulation of the sural nerve. 2. Stimulation of the cortex or in the CP preferentially reduced the amplitude of the N1 and N2 waves of the cord dorsum potential evoked by stimulation of the sural nerve, without affecting the N3 wave. Stimulation of the PAG, on the other hand, reduced the amplitude of the N3 wave with little effect on the N1 and N2 waves. 3. The activity of 62 STT neurons was recorded extracellularly. Stimulation of the PAG or the cortex/CP inhibited nonpreferentially the responses of the neurons in the superficial laminae to all afferent inputs. On the other hand, stimulation of the PAG or the cortex/CP inhibited preferentially the responses of most STT neurons in deep layers of the dorsal horn to the small or large afferent input, respectively. 4. Thirty-five neurons were recorded intracellularly. The membrane potential of the neurons averaged -45.5 +/- 10.1 (SD) mV. All neurons were recorded in laminae III-VI; the neurons were of the wide-dynamic-range (WDR) type and had background activity. 5. The inhibitory effects of stimulation of the PAG were tested on all 35 neurons. In 32 of the neurons, stimulation of the PAG evoked a hyperpolarization. The background activity of the neurons was reduced (generally it completely ceased) by the hyperpolarization. In three neurons stimulation of the PAG did not evoke a hyperpolarization and the background activity of the neurons did not change. Nevertheless, the responses of these three neurons to afferent input were inhibited by stimulation in the PAG. 6. The inhibitory effects of stimulating the cortex and/or the CP were tested in 26 of the 35 neurons. Stimulation of the cortex and/or the CP evoked a hyperpolarization in all the neurons, although, in 10 of the 26 neurons, stimulation of the CP also evoked a depolarization. The hyperpolarization generally blocked the background activity of the neurons. 7. The effective stimuli in the PAG and the cortex/CP to evoke a hyperpolarization in STT neurons were short, high-frequency trains of pulses.(ABSTRACT TRUNCATED AT 400 WORDS)
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Keupp, Stefanie, Farhan Abedin, Lena Jeanson, Carolin Kade, Josefine Kalbitz, Rowan Titchener, Thomas Mussweiler, Thomas Bugnyar, and Julia Fischer. "Performance-based Social Comparisons in Humans and Long-tailed Macaques." Animal Behavior and Cognition 8, no. 3 (August 3, 2021): 325–50. http://dx.doi.org/10.26451/abc.08.03.02.2021.
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Social comparisons are a fundamental feature of human thinking and affect self-evaluations and task performance. Little is known about the evolutionary origins of social comparison processes, however. Previous studies that investigated performance-based social comparisons in nonhuman primates yielded mixed results. We report three experiments that aimed (a) to explore how the task type may contribute to performance in monkeys, and (b) how a competitive set-up affects monkeys compared to humans. In a co-action touchscreen task, monkeys were neither influenced by nor interested in the performance of the partner. This may indicate that the experimental set-up was not sufficiently relevant to trigger social comparisons. In a novel co-action foraging task, monkeys increased their feeding speed in competitive and co-active conditions, but not in relation to the degree of competition. In an analogue of the foraging task, human participants were affected by partner performance and experimental context, indicating that the task is suitable to elicit social comparisons in humans. Our studies indicate that specifics of task and experimental setting are relevant to draw the monkeys’ attention to a co-actor and that, in line with previous research, a competitive element was crucial. We highlight the need to explore what constitutes “relevant” social comparison situations for monkeys as well as nonhuman animals in general, and point out factors that we think are crucial in this respect (e.g., task type, physical closeness, and the species’ ecology). We discuss that early forms of social comparisons evolved in purely competitive environments with increasing social tolerance and cooperative motivations allowing for more fine-grained processing of social information. Competition driven effects on task performance might constitute the foundation for the more elaborate social comparison processes found in humans, which may involve context-dependent information processing and metacognitive monitoring.
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Mekonnen, Addisu, Afework Bekele, Graham Hemson, Eyob Teshome, and Anagaw Atickem. "Population size and habitat preference of the Vulnerable Bale monkey Chlorocebus djamdjamensis in Odobullu Forest and its distribution across the Bale Mountains, Ethiopia." Oryx 44, no. 4 (October 2010): 558–63. http://dx.doi.org/10.1017/s0030605310000748.
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AbstractThe Bale monkey Chlorocebus djamdjamensis is a little-known primate endemic to the south-eastern highlands of Ethiopia. From August 2007 to May 2008 we surveyed to determine the species' habitat preferences and population size in the Odobullu Forest and its range across the Bale Mountains. In Odobullu Forest a total of 136 transects of 1.8–3.0 km were surveyed over a total distance of 280 km. Bale monkey groups were encountered only in bamboo forest, suggesting that the species is a bamboo forest specialist. The density and population size of the Bale monkey in the bamboo forest of Odobullu Forest were estimated to be 121–141 km-2 and 1,718–2,002, respectively. At a larger scale, we assessed the distribution of the Bale monkey in 40% of the bamboo forest across the Bale Mountains within the species’ altitudinal range of 2,400–3,250 m. We identified the areas to be surveyed using a 200 m digital elevation model and a 10-m resolution satellite image. We found the Bale monkey in five areas, three of which are previously unrecorded locations for the species. The Bale monkey is now categorized as Vulnerable on the IUCN Red List, partly based on the results of our surveys. Although extensive, our surveys did not cover all of the species’ potential habitat and further surveys are required across all of the bamboo forest of the Bale Mountains and Sidamo region (the western extension of the Bale Mountains).
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Easton, Julian, Nerissa Chao, Felix Mulindahabi, Nicolas Ntare, Louis Rugyerinyange, and Innocent Ndikubwimana. "Status and conservation of the only population of the Vulnerable owl-faced monkey Cercopithecus hamlyni in Rwanda." Oryx 45, no. 3 (June 7, 2011): 435–38. http://dx.doi.org/10.1017/s0030605310001468.
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AbstractThe elusive, Vulnerable owl-faced monkey Cercopithecus hamlyni is a rare and little studied species and one of the least known of the African Cercopithecidae. This study describes the distribution and relative abundance of the only known population in East Africa, in Nyungwe National Park, Rwanda. This species is restricted to a small (32 km2) area of bamboo and bamboo–forest mix in the southern sector of the Park, close to the international border with Burundi. We present the first empirical data of its abundance in the bamboo forests of Nyungwe. A total length of 185 km of transect were surveyed to estimate relative abundance of diurnal primates. Encounter rates with the owl-faced monkey were 0.081 groups km-1 (n = 15). Mean group size was 3.6 individuals. Eight independent photographs of C. hamlyni were obtained from five camera traps during 182 camera-days. Four other species of primates occur in the bamboo forest: eastern chimpanzee Pan troglodytes schweinfurthii, Angola colobus Colobus angolensis, L’Hoest’s monkey Cercopithecus l’hoesti and blue monkey Cercopithecus mitis. The main threats to the bamboo forest are from the illegal harvesting of bamboo, trapping and tree-cutting. These threats originate from both Rwanda and Burundi. There is an urgent need for conservation action to halt the destruction and degradation of the bamboo forest and to ensure the long-term survival of the owl-faced monkey in Rwanda.
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Adams, Daniel L., John R. Economides, Cristina M. Jocson, and Jonathan C. Horton. "A Biocompatible Titanium Headpost for Stabilizing Behaving Monkeys." Journal of Neurophysiology 98, no. 2 (August 2007): 993–1001. http://dx.doi.org/10.1152/jn.00102.2007.
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Many neurophysiological experiments involving monkeys require that the head be stabilized while the animal performs a task. Often a post is attached to the skull to accomplish this goal, using a headcap formed from dental acrylic. We describe a new headpost, developed by refinement of several prototypes, and supply an AutoCAD file to aid in machine shop production. This headpost is fabricated from a single piece of commercially pure titanium. It has a footplate consisting of four limbs arranged in the configuration of a “K.” These are bent during surgery to match the curvature of the skull and attached with specialized titanium bone screws. Headposts were implanted in seven rhesus monkeys ranging in age from 2 yr to adult. None has been rejected after up to 17 mo of regular use. They require little or no daily toilette and create only a 0.80-cm2 defect in the scalp. Computed tomography after implantation showed that the skull undergoes remodeling to embed the footplate in bone. This finding was confirmed by necropsy in two subjects. The outer table of the skull had grown over the titanium footplate, whereas the inner table had thickened to bury the tips of the titanium screws. The remarkable strength of the skull/implant bond was demonstrated by applying increasing amounts of torque to the headpost. At 26.3 Nm, the headpost tore from its metal footplate, but no screws came loose. The excellent performance of this implant is explained by integration of biocompatible titanium into remodeled bone tissue. The headpost is simpler to implant, more securely anchored, easier to maintain, and less obtrusive than devices attached with acrylic.
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Krishna, Aravind, Seiji Tanabe, and Adam Kohn. "Decision Signals in the Local Field Potentials of Early and Mid-Level Macaque Visual Cortex." Cerebral Cortex 31, no. 1 (August 27, 2020): 169–83. http://dx.doi.org/10.1093/cercor/bhaa218.
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Abstract The neural basis of perceptual decision making has typically been studied using measurements of single neuron activity, though decisions are likely based on the activity of large neuronal ensembles. Local field potentials (LFPs) may, in some cases, serve as a useful proxy for population activity and thus be useful for understanding the neural basis of perceptual decision making. However, little is known about whether LFPs in sensory areas include decision-related signals. We therefore analyzed LFPs recorded using two 48electrode arrays implanted in primary visual cortex (V1) and area V4 of macaque monkeys trained to perform a fine orientation discrimination task. We found significant choice information in low (0–30 Hz) and higher (70–500 Hz) frequency components of the LFP, but little information in gamma frequencies (30–70 Hz). Choice information was more robust in V4 than V1 and stronger in LFPs than in simultaneously measured spiking activity. LFP-based choice information included a global component, common across electrodes within an area. Our findings reveal the presence of robust choice-related signals in the LFPs recorded in V1 and V4 and suggest that LFPs may be a useful complement to spike-based analyses of decision making.
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Ratan Murty, N. Apurva, and S. P. Arun. "Effect of silhouetting and inversion on view invariance in the monkey inferotemporal cortex." Journal of Neurophysiology 118, no. 1 (July 1, 2017): 353–62. http://dx.doi.org/10.1152/jn.00008.2017.
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We effortlessly recognize objects across changes in viewpoint, but we know relatively little about the features that underlie viewpoint invariance in the brain. Here, we set out to characterize how viewpoint invariance in monkey inferior temporal (IT) neurons is influenced by two image manipulations—silhouetting and inversion. Reducing an object into its silhouette removes internal detail, so this would reveal how much viewpoint invariance depends on the external contours. Inverting an object retains but rearranges features, so this would reveal how much viewpoint invariance depends on the arrangement and orientation of features. Our main findings are 1) view invariance is weakened by silhouetting but not by inversion; 2) view invariance was stronger in neurons that generalized across silhouetting and inversion; 3) neuronal responses to natural objects matched early with that of silhouettes and only later to that of inverted objects, indicative of coarse-to-fine processing; and 4) the impact of silhouetting and inversion depended on object structure. Taken together, our results elucidate the underlying features and dynamics of view-invariant object representations in the brain. NEW & NOTEWORTHY We easily recognize objects across changes in viewpoint, but the underlying features are unknown. Here, we show that view invariance in the monkey inferotemporal cortex is driven mainly by external object contours and is not specialized for object orientation. We also find that the responses to natural objects match with that of their silhouettes early in the response, and with inverted versions later in the response—indicative of a coarse-to-fine processing sequence in the brain.
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Lexer, Christian, and Alex Widmer. "The genic view of plant speciation: recent progress and emerging questions." Philosophical Transactions of the Royal Society B: Biological Sciences 363, no. 1506 (June 25, 2008): 3023–36. http://dx.doi.org/10.1098/rstb.2008.0078.
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The genic view of the process of speciation is based on the notion that species isolation may be achieved by a modest number of genes. Although great strides have been made to characterize ‘speciation genes’ in some groups of animals, little is known about the nature of genic barriers to gene flow in plants. We review recent progress in the characterization of genic species barriers in plants with a focus on five ‘model’ genera: Mimulus (monkey flowers); Iris (irises); Helianthus (sunflowers); Silene (campions); and Populus (poplars, aspens, cottonwoods). The study species in all five genera are diploid in terms of meiotic behaviour, and chromosomal rearrangements are assumed to play a minor role in species isolation, with the exception of Helianthus for which data on the relative roles of chromosomal and genic isolation factors are available. Our review identifies the following key topics as being of special interest for future research: the role of intraspecific variation in speciation; the detection of balancing versus directional selection in speciation genetic studies; the timing of fixation of alleles of major versus minor effects during plant speciation; the likelihood of adaptive trait introgression; and the identification and characterization of speciation genes and speciation gene networks.
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Albrecht, Duane G. "Visual cortex neurons in monkey and cat: Effect of contrast on the spatial and temporal phase transfer functions." Visual Neuroscience 12, no. 6 (November 1995): 1191–210. http://dx.doi.org/10.1017/s0952523800006817.
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AbstractThe responses of simple cells (recorded from within the striate visual cortex) were measured as a function of the contrast and the frequency of sine-wave grating patterns in order to explore the effect of contrast on the spatial and temporal phase transfer functions and on the spatiotemporal receptive field. In general, as the contrast increased, the phase of the response advanced by approximately 45 ms (approximately one-quarter of a cycle for frequencies near 5 Hz), although the exact value varied from cell to cell. The dynamics of this phase-advance were similar to the dynamics of the amplitude: the amplitude and the phase increased in an accelerating fashion at lower contrasts and then saturated at higher contrasts. Further, the gain for both the amplitude and the phase appeared to be governed by the magnitude of the contrast rather than the magnitude of the response. For the spatial phase transfer function, variations in contrast had little or no systematic effect; all of the phase responses clustered around a single straight line, with a common slope and intercept. This implies that the phase-advance was not due to a change in the spatial properties of the neuron; it also implies that the phase-advance was not systematically related to the magnitude of the response amplitude. On the other hand, for the temporal phase transfer function, the phase responses fell on five straight lines, related to the five steps in contrast. As the contrast increased, the phase responses advanced such that both the slope and the intercept were affected. This implies that the phase-advance was a result of contrast-induced changes in both the response latency and the shape/symmetry of the temporal receptive field.
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Chagas, RRD, and SF Ferrari. "Population parameters of the endangered titi monkey, Callicebus coimbrai Kobayashi and Langguth, 1999, in the fragmented landscape of southern Sergipe, Brazil." Brazilian Journal of Biology 71, no. 3 (August 2011): 569–75. http://dx.doi.org/10.1590/s1519-69842011000400001.
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The recently-discovered titi, Callicebus coimbrai, is endemic to the coastal Brazilian Atlantic Forest south of the São Francisco River, a region with a long tradition of deforestation. While a number of C. coimbrai populations have now been identified, little is known about basic population parameters. Considering the importance of this information for conservation planning, the population of a site in southern Sergipe (with a total area of forest of approximately 500 ha) was surveyed between April and October 2008. Standard line transect procedures were used in the four largest fragments, and additional monitoring included the use of playback broadcasts for the observation of titi groups. The presence of titis was confirmed in all the forest fragments at the site, including one of only five hectares. Two other primates - Callithrix jacchus and Cebus xanthosternos - were also recorded at the site, but were less abundant than titis. A total transect walk of 476 km provided 164 sightings of primates, the majority of which (104) were of Callicebus coimbrai. Titi groups ranged in size between two and five individuals. The most reliable estimate of overall population density, derived from the combined data set, was 12.6 individuals per km²;, although density was much higher in smaller (more disturbed) fragments. The total population of Callicebus coimbrai at the site was estimated to be at least 50 individuals, which may represent a considerable proportion of the population of the species remaining in the wild. In addition to its apparent tolerance of habitat fragmentation, densities of C. coimbrai recorded at the site compare favourably with those of other Atlantic Forest titi species.
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PETERSON, BETH B., and DENNIS M. DACEY. "Morphology of wide-field bistratified and diffuse human retinal ganglion cells." Visual Neuroscience 17, no. 4 (July 2000): 567–78. http://dx.doi.org/10.1017/s0952523800174073.
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To study the detailed morphology of human retinal ganglion cells, we used intracellular injection of horseradish peroxidase and Neurobiotin to label over 1000 cells in an in vitro, wholemount preparation of the human retina. This study reports on the morphology of 119 wide-field bistratified and 42 diffuse ganglion cells. Cells were analyzed quantitatively on the basis of dendritic-field size, soma size, and the extent of dendritic branching. Bistratified cells were similar in dendritic-field diameter (mean ± s.d. = 682 ± 130 μm) and soma diameter (mean ± s.d. = 18 ± 3.3 μm) but showed a broad distribution in the extent of dendritic branching (mean ± s.d. branch point number = 67 ± 32; range = 15–167). Differences in the extent of branching and in dendritic morphology and the pattern of branching suggest that the human retina may contain at least three types of wide-field bistratified cells. Diffuse ganglion cells comprised a largely homogeneous group whose dendrites ramified throughout the inner plexiform layer. The diffuse cells had similar dendritic-field diameters (mean ± s.d. = 486 ± 113 μm), soma diameters (mean ± s.d. = 16 ± 2.3 μm), and branch points numbers (mean ± s.d. = 92 ± 32). The majority had densely branched dendritic trees and thin, very spiny dendrites with many short, fine, twig-like thorny processes. Five of the diffuse cells had much more sparsely branched dendritic trees (<50 branch points) and less spiny dendrites, suggesting that there are possibly two types of diffuse ganglion cells in human retina. Although the presence of a diversity of large bistratified and diffuse ganglion cells has been observed in a variety of mammalian retinas, little is known about the number of cell types, their physiological properties, or their central projections. Some of the human wide-field bistratified cells in the present study, however, show morphological similarities to monkey large bistratified cells that are known to project to the superior colliculus.
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Segraves, M. A., and K. Park. "The relationship of monkey frontal eye field activity to saccade dynamics." Journal of Neurophysiology 69, no. 6 (June 1, 1993): 1880–89. http://dx.doi.org/10.1152/jn.1993.69.6.1880.
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1. In this study, we compared the temporal waveforms of the activity of monkey frontal eye field movement neurons with the dynamics of saccadic eye movements. 2. Movement neurons in the frontal eye field were selected according to previously published criteria. They had little or no response to visual stimuli in a fixation task, and equivalent activity before visually guided and memory-guided saccades. We studied corticotectal neurons and corticopontine neurons identified by antidromic excitation, as well as neurons whose projections were not identified. 3. These neurons had a peak activation at a mean of 13 ms before the saccade began. However, rather than falling off rapidly as the saccade ended, most neurons continued to fire after the saccade, returning to baseline at a mean of 93 ms after the end of the saccade. 4. We measured the decrement in activity for these neurons during the saccade. Although a few neurons showed decrements of > 60% of their peak activity level, the average activity dropped only 16.9%, with some neurons actually showing a rise in activity during the saccade. If we ignored the latency between peak in activity and saccade start and measured the fall in activity for a period equal to one saccade duration after the peak, the average drop in activity was still only 34.9%. Thus the activity of these neurons did not appear to be closely related to dynamic motor error, which falls from its maximum value to zero over the time course of a saccade. 5. These results suggest that a focus of movement activity within the topographic map in the frontal eye field specifies the amplitude and direction for an impending saccade, whereas the peak of movement activity signals the time to initiate a saccade. 6. Unlike the superior colliculus, the activity of frontal eye field movement neurons does not appear to be related to dynamic events that occur during the saccade, such as motor error.
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McManners, J. "Voltaire and the Monks." Studies in Church History 22 (1985): 319–42. http://dx.doi.org/10.1017/s0424208400008044.
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‘You can never cross the Pont Neuf without seeing a monk, a white horse and a whore’, ran the proverb – which was hard luck on the two ladies who stood there and saw the first two but could not find the third: ‘Pour la catin, vous et moi nous n’en sommes pas en peines’. Members of the religious Orders in their costumes of black, white, brown and grey were a feature of the scene in the streets of every town, and everyone had a monk or nun among their relatives. Voltaire’s sardonic examples of the characteristic features of the civilisation of his day included them: ‘man will always be what he is now; this does not mean to say, however, that there will always be fine cities, cannons firing a shot of 24 lbs weight, comic operas and convents of nuns’. Routine gossip slipped naturally into analogies drawn from the cloister – she is as fat as a monk; they were like children at a window crying out when they first see a Capucin friar; you are like a novice who climbs the walls looking for a lover, while the nuns in the chapel pray for her. Voltaire uses monastic titles in jocular descriptions of himself and his friends. He is the ‘old hermit’, the ‘lay brother’, the ‘solitary’, ‘brother Voltaire, dead to the world and in love with his cell and his convent’, and once, when his play Octave et le jeune Pompée was a flop, he decided to be, for a while, ‘the little ex-Jesuit’, ‘le petit défroqué’. He hopes ‘brother’ Helvétius will be elected to the Academy: ‘these are the most ardent prayers of the monk Voltairius, who from his lonely cell unites himself in spirit with his brethren’. The badinage of monastic seclusion hinted at protest at his long exile from Paris; it also served to mask the social distinctions, which, in spite of familiarity and, even, friendship, were never forgotten between the court grandees and the intellectuals. It was easier for Choiseul to write to him as ‘mon cher solitaire’, just as Voltaire avoided routine sycophancy by writing, with exaggerated deference, to Richelieu as ‘mon héros’.
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Snodderly, D. M., and M. Gur. "Organization of striate cortex of alert, trained monkeys (Macaca fascicularis): ongoing activity, stimulus selectivity, and widths of receptive field activating regions." Journal of Neurophysiology 74, no. 5 (November 1, 1995): 2100–2125. http://dx.doi.org/10.1152/jn.1995.74.5.2100.
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1. In alert macaque monkeys, multiunit activity is encountered in an alternating sequence of silent and spontaneously active zones as an electrode is lowered through the striate cortex (V1). 2. Individual neurons that are spontaneously active in the dark usually have a maintained discharge in the light. Because both types of discharge occur in the absence of deliberate stimulation, we call them the "ongoing" activity. The zones with ongoing activity correspond to the cytochrome oxidase (CytOx)-rich geniculorecipient layers 4A, 4C, and 6, whereas the adjacent layers 2/3, 4B, and 5 have little ongoing activity. 3. The widths of receptive field activating regions (ARs) are positively correlated with the cells' ongoing activity. Cells with larger ARs are preferentially located in the CytOx-rich (input) layers, and many are unselective for stimulus orientation. However, approximately 90% of the cells in the silent layers are orientation selective, and they often have small ARs. 4. The laminar distribution of selectivity for orientation and direction of movement in alert animals is consistent with earlier results from anesthetized animals, but the laminar distribution of AR widths differs. In alert macaques, the ARs of direction-selective cells in layer 4B and of orientation-selective cells in layer 5 are among the smallest in V1. 5. Our findings indicate that the input layers of V1 (4A, 4C, and 6) have a diversity of AR widths, including large ones. Cortical processing produces receptive fields in some of the output layers (4B and 5) that are restricted to small ARs with high resolution of spatial position. These results imply potent lateral and/or interlaminar interactions in alert animals in early cortical processing. The diversity of AR widths generated in V1 may contribute to detection of fine detail in the presence of contrasting backgrounds--the early stages of figure-ground discrimination.
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Cano, Luis Santiago, and José Luis Tellería. "Local ecological knowledge as a tool for assessing the status of threatened vertebrates: a case study in Vietnam." Oryx 47, no. 2 (April 2013): 177–83. http://dx.doi.org/10.1017/s0030605311001669.
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AbstractThis study draws on the local ecological knowledge of 58 hunters from seven communes in the Ngoc Son Ngo Luong Nature Reserve (Hoa Binh province, North Vietnam) to examine the local status of 40 threatened vertebrates. The reserve forms part of a biodiversity-rich mountainous corridor. Respondents were shown photographs of the species and asked to rate their abundance on a scale of 0–3 (0, extinct; 3, very abundant) in two periods: pre-1975 (before Doi Moi) and in 2009. The results show that 39 species have lived in the area and five are now extinct (Delacour's langur Trachypithecus delacouri, northern white-cheeked crested gibbon Nomascus leucogenys, dhole Cuon alpinus, oriental small-clawed otter Aonyx cinereus, Indochinese tiger Panthera tigris corbetti) and the presence of another six is doubtful (Phayre's leaf-monkey Trachypithecus phayrei ssp. crepuscula, sun bear Helarctos malayanus, binturong Arctictis binturong, fishing cat Prionailurus viverrinus, leopard Panthera pardus, wreathed hornbill Anorrhinus undulatus). The results show a general decline in numbers and abundance, with mammals declining fastest, especially carnivores and primates. The differences in abundance between species have narrowed since 1975, converging towards trends of general impoverishment at similar low abundances. The survey results were similar among communes and also concord with the findings of research in nearby areas. This study demonstrates the usefulness of local ecological knowledge for planning, decision-making and management of protected areas in the absence of historical records or financial resources for conducting intensive fieldwork in remote and little-known areas.
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Rai, Y., U. Karki, S. Thapaliya, and R. Molina. "Neuropsychiatry Training in Nepal: Experiences of Trainees and Psychiatrists." Journal of Psychiatrists' Association of Nepal 9, no. 1 (September 18, 2020): 23–28. http://dx.doi.org/10.3126/jpan.v9i1.31312.
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Introduction: Training, practice and continuing professional development in neuropsychiatry and clinical neuroscience vary across different countries. However, little is known about the opinions of the Nepalese psychiatrists about the provision of neuropsychiatry training. This study evaluates the current training in neuropsychiatry and clinical neurosciences during the postgraduate psychiatry training and reflect on current practice.
Material And Method: The participants were psychiatrists (qualified and psychiatry residents). An online questionnaire using Survey Monkey electronic Platform was emailed with a uniform resource locator (URL).
Results: Sixty-four out of ninety-five participants responded with response rate of 65.3%. Two-third of the respondents were qualified psychiatrists. The duration of neurology rotation ranged from 1 to 3 months and it was reported to be mandatory. Two-thirds reported that there is no clinical neuropsychiatry training during psychiatry residency. On a ten-point Likert scale (with 10 being the highest possible score), the participants rated their neuropsychiatry training as 5.16±1.84 while they rated the necessity for further training in neuropsychiatry as 7.92±1.96. Two-thirds identified a lack of interest by the specialty society as an obstacle for the implementation of neuropsychiatry training for psychiatrists. More than half viewed that neuropsychiatry training to be incorporated into the existing psychiatry training scheme whereas three-fifths favoured a one-year specific training program in neuropsychiatry after completion of psychiatry training.
Conclusion: The current psychiatry training is inadequate to meet substantial neuropsychiatry training opportunities for a high proportion of psychiatrists in Nepal. This finding may be used to improve and standardize neuropsychiatry training in postgraduate psychiatry training.
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Muthukutty, A. "பிற்கால சோழர்கள் காலத்தில் பெண்களும் கலை வளர்ச்சியும்." Shanlax International Journal of Tamil Research 5, no. 1 (July 1, 2020): 123–33. http://dx.doi.org/10.34293/tamil.v5i1.3406.
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Man lived as a savage in ancient times. At that time, man wandered like an animal, not knowing how to make a home and what to wear and what to eat. Then he gradually became civilized and met his needs and got civilized life from animal life. What helped him to become civilized were the various professions in which he learned little by little.It can be said that the arts are all professions that contribute to the well-being of man. It is these arts that give beauty and pleasure to the human mind. The arts that are considered to be special can be divided into five, namely, architecture, sculpture, painting, music, and epic, and afterwards koothu and dramas are combined into seven. The arts flourished wherever civilized people lived.We can find evidence in the various temples and palaces that the Chola monks also gave prominence to these arts. During the Chola period women lived freely without any restrictions. During the Sangam era, Viraliyar and Panar continued to develop music and koothu and rejuvenated the society. There is ample evidence that the Cholas followed the arts in worship as well.
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Warren, S., H. A. Hamalainen, and E. P. Gardner. "Coding of the spatial period of gratings rolled across the receptive fields of somatosensory cortical neurons in awake monkeys." Journal of Neurophysiology 56, no. 3 (September 1, 1986): 623–39. http://dx.doi.org/10.1152/jn.1986.56.3.623.
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In order to measure the texture coding capabilities of motion-, direction-, and orientation-sensitive neurons in SI cortex, we rolled wheels with surface milled gratings across their receptive fields. Gratings of spatial periods 0.8-9.6 mm were presented in pseudorandom order; each was tested 5-20 times in the distal, proximal, radial, and ulnar directions. Thirty eight cortical neurons were studied with three to eight different gratings in order to determine the effect of spatial period on neuronal firing rates. While all 38 cells had their firing rates modulated by motion of the gratings, only 11 neurons were able to distinguish changes in its spatial period. These cells had small receptive fields located on the hand. Most motion-sensitive neurons showed little effect of spatial period on firing rates and had relatively flat frequency response curves. One showed decreased firing to spatial periods over the range 0.8-6.4 mm; three others increased their firing rates over the range 0.8-3.2 mm, followed by a decline in activity to larger spatial periods. Direction- and orientation-sensitive neurons showed only minor changes in firing rates as a function of spatial period. Sixteen cells showed flat frequency response functions, three showed increased firing rates, and four decreased firing rates as spatial period of the grating increased. Direction and orientation preferences were maintained over the range 0.8-9.6 mm for all 23 neurons tested. Although four cells showed a drop in direction index (DI) as the spatial period was increased, none showed a loss of direction sensitivity, as DI was greater than 35 for all gratings tested. Two neurons showed increased firing to motion in the last-preferred direction and two others decreased firing in the best direction. The remaining 19 neurons showed parallel effects of texture in all directions. Some motion-sensitive neurons showed weak direction preferences when tested with fine gratings; these preferences disappeared with coarser gratings, due to increased responsiveness to motion in the least-preferred direction. These data demonstrate that movement-sensitive neurons do not require continuous trajectories across the skin but instead sequential activation of points aligned in a specific path. Cortical neurons appear capable of integrating information from points separated by up to 9 mm, as long as they are presented in the appropriate temporal sequence. Firing rates of direction- and orientation-sensitive neurons are more profoundly modified by changes in the direction of motion across the skin, and the temporal order of stimulation, than by alterations in the spatial characteristics of the moving stimulus.(ABSTRACT TRUNCATED AT 400 WORDS)
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Pizo, Marco A., and Paulo S. Oliveira. "Removal of seeds from vertebrate faeces by ants: effects of seed species and deposition site." Canadian Journal of Zoology 77, no. 10 (December 1, 1999): 1595–602. http://dx.doi.org/10.1139/z99-126.
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We investigated the removal of seeds of three species (Philodendron corcovadense and Philodendron appendiculatum (Araceae) and Aechmea sp. (Bromeliaceae)) from the faeces of capuchin monkeys (Cebus apella) by ants in a lowland Atlantic rain forest in southeast Brazil. We examined seed removal by ants in the understory and in treefall gaps, which probably differ greatly in microclimatic conditions. We examined whether seed removal varied among seed species, between understory and gaps, and also among five gaps that differed in size and age. We recorded 17 ant species (4 subfamilies, 9 genera) on the faeces, 8 of which were observed removing seeds. On average, 68% of the seeds had been removed from faecal portions containing 15 seeds each after 24 h. For both the understory versus gap and the among-gap comparisons, seed species significantly affected the proportion of seeds removed, while deposition site (i.e., understory versus gaps or among gaps) had no effect. We interpreted these results as a consequence of the equalizing effect of three myrmicine species (Pheidole sp. 1, Pheidole sp. 3, and Pheidole sp. 7) upon seed removal. These ant species were the most frequently recorded on faeces (63 and 44% in understory and gap sites, respectively, for all three Pheidole species combined) and are among the most abundant litter-foraging ants in the understory and gaps. Because of the high abundance of ants in Neotropical forests, and the flexibility of some ant species in the microclimatic gradient they use, seed removal is likely to be less affected by differences in microclimatic conditions between understory and gaps than by the seed species involved.
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Kim, Hwansoo. "Two Incarnations, One Person: The Complexity of Kim Iryŏp’s Life." Journal of Korean Studies 26, no. 1 (March 1, 2021): 51–71. http://dx.doi.org/10.1215/07311613-8747707.
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Abstract Kim Iryŏp (Kim Wŏnju, 1896‒1971) was a pioneering feminist and prolific writer who left lay life to become a Buddhist nun. The bifurcation of her life between the secular and religious has generated two separate narratives, with Korean feminist studies focusing on Iryŏp as a revolutionary thinker and Buddhist studies centering on Iryŏp as an influential Buddhist nun. When divided this way, the biography of each career reads more simply. However, by including two significant but unexplored pieces of her history that traverse the two halves of her narrative, Iryŏp emerges as a more complex figure. The first is her forty-five-year relationship with the Buddhist monk Paek Sŏng’uk (1897‒1981). The second is how she extended some of her early feminism into monastic life but said little about the marginalization of nuns in Buddhism’s highly patriarchal system. In both her relationship with Paek and her feminism, Iryŏp drew on the Buddhist teaching of nonself, in which the “big I” is beyond gender. Thus, Iryŏp repositions herself as having attained big I, while Paek remained stuck in “small I.” Yet, while she finds equality with monks through an androgynous big I, none of her writings contest Korean Buddhism’s androcentric institutional structure.
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Moatt, Michele. "Discipline and the Rule of Basil in Walter Daniel’s Life of Ailred of Rievaulx." Studies in Church History 43 (2007): 169–79. http://dx.doi.org/10.1017/s0424208400003181.
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He made his little body free of everything that is pleasant in this present life. He sacrificed himself on the altar of unfailing suffering: hardly any flesh clung to his bones; his lips alone remained a frame to his teeth. The excessive emaciation of his body and the thinness of his face gave an angelic expression to his countenance. Eating scarcely anything and drinking less, by his unbelievable fasting, he lost altogether, and no wonder, the desire for food.So wrote Walter Daniel of his erstwhile friend and mentor, Ailred, in his Life of Ailred of Rievaulx, some time after Ailred’s death in 1167. This was written in an attempt to demonstrate his abbot’s sanctity with the clear hope that as a result he might eventually be canonized. It is hard, therefore, to understand why this image of the abbot who, if we are to believe Walter, governed ‘over one hundred monks and five hundred laymen’, s is so at odds with the instructions to abbots contained within the generally moderate Rule of Benedict, which governed the lives of all Cistercian monks. The Cistercians interpreted the Rule more rigidly than the Benedictines, but even for them there should be no ostentatious exhibitions of pious self-starvation since a monk must exhibit mediocritas or moderation in all he did. Moreover, regulation of eating must not be at the expense of life itself. In order to resolve Walter’s anomalous portrait of his abbot I will first seek the source of the textual representation of the ascetic Ailred and then, very briefly, consider its relationship to what we can surmise about Ailred’s actual practices in order to hypothesise about what kind of influences helped to form them. In the process, I will suggest that the extreme form of monastic disciplina, exemplified by the literary model of Ailred, causes us to question Foucault’s notion that: ‘Discipline produces practiced bodies, docile bodies. Discipline increases the forces of the body (in economic terms of utility) and diminishes these same forces (in political terms of obedience).’
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DAVENPORT, CHRISTOPHER M., PETER B. DETWILER, and DENNIS M. DACEY. "Functional polarity of dendrites and axons of primate A1 amacrine cells." Visual Neuroscience 24, no. 4 (May 29, 2007): 449–57. http://dx.doi.org/10.1017/s0952523807070010.
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The A1 cell is an axon-bearing amacrine cell of the primate retina with a diffusely stratified, moderately branched dendritic tree (∼400 μm diameter). Axons arise from proximal dendrites forming a second concentric, larger arborization (>4 mm diameter) of thin processes with bouton-like swellings along their length. A1 cells are ON-OFF transient cells that fire a brief high frequency burst of action potentials in response to light (Stafford & Dacey, 1997). It has been hypothesized that A1 cells receive local input to their dendrites, with action potentials propagating output via the axons across the retina, serving a global inhibitory function. To explore this hypothesis we recorded intracellularly from A1 cells in an in vitro macaque monkey retina preparation. A1 cells have an antagonistic center-surround receptive field structure for the ON and OFF components of the light response. Blocking the ON pathway with L-AP4 eliminated ON center responses but not OFF center responses or ON or OFF surround responses. Blocking GABAergic inhibition with picrotoxin increased response amplitudes without affecting receptive field structure. TTX abolished action potentials, with little effect on the sub-threshold light response or basic receptive field structure. We also used multi-photon laser scanning microscopy to record light-induced calcium transients in morphologically identified dendrites and axons of A1 cells. TTX completely abolished such calcium transients in the axons but not in the dendrites. Together these results support the current model of A1 function, whereby the dendritic tree receives synaptic input that determines the center-surround receptive field; and action potentials arise in the axons, which propagate away from the dendritic field across the retina.
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Mink, J. W., and W. T. Thach. "Basal ganglia motor control. III. Pallidal ablation: normal reaction time, muscle cocontraction, and slow movement." Journal of Neurophysiology 65, no. 2 (February 1, 1991): 330–51. http://dx.doi.org/10.1152/jn.1991.65.2.330.
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1. Inactivation of the portions of globus pallidus pars interna (GPi) containing the greatest concentration of wrist-related neurons was achieved in two rhesus monkeys with microinjections of muscimol (temporary) and kainic acid (permanent). 2. After muscimol injection, there was onset within 30 s of 1) tonic and phasic coactivation of wrist flexors and extensors; 2) slightly greater activation of the flexors, giving a flexor bias in postural holds and the endpoint of movements; and 3) slowness of all movements with a prolonged movement time. Nevertheless, 4) movements made by lessening prior loaded muscle activity (to move in the direction of the load) were slower than movement made by increasing muscle activity (to move against the direction of the load). Despite marked slowing of all movements, there was 5) a normal reaction time for movement onset. Finally, there was 6) a reduced amplitude of most movements. Open room behavior included 7) spiraling contralateral to the lesion while walking. Effects were reproducible (12 injections), were apparent for 7-8 h and were usually completely gone by the next day's testing. 3. After kainic acid injection, there was a period of mixed effects, followed by a period of permanent defects (observed for up to 24 days) that duplicated the temporary effects of muscimol. 4. By contrast, muscimol inactivation of the cerebellar dentate nucleus resulted in 1) a prolonged reaction time and 2) an increased variability of movement trajectory, but 3) without change in movement time or peak velocity. Open room behavior included overshoot in reaching for fruit with the forelimb ipsilateral to the injection. 5. From the facts that normal pallidal neurons fire constantly, that pallidal neurons inhibit their target neurons, and that the muscimol effect was immediate, we conclude that the release of the target neurons from the tonic inhibition allowed them to fire in patterns that promoted a maintained state of cocontraction of agonist and antagonist muscles. From the fact that movement time was prolonged, we conclude that the maintained state of neural activity that caused the muscle cocontraction interfered with the commands for voluntary movement, which were generated by other mechanisms. From the fact that reaction time for movement onset was normal, we conclude that the pallidal neurons may play little or no role in the voluntary initiation of these movements, which are instead generated by other structures that include the anterior cerebral cortex and the lateral cerebellum.
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Šiūlys, Fr Rimgaudas. "The Spirituality of st Bruno of Querfurt." Lithuanian Historical Studies 14, no. 1 (December 28, 2009): 1–10. http://dx.doi.org/10.30965/25386565-01401001.
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This article analyses the spirituality of St. Bruno of Querfurt, as expressed in his writings. In his Life of the Five Brethren he presents the plan of Otto III to send some of St Romuald’s most zealous disciples to the Slavonic countries to build a monastery near the pagan lands. In this way the ‘three obligations’ seeking the Lord’s path, namely: for the new arrivals – the community life they desire, for those mature and seeking the Living God – golden solitude, for those desiring to be free and with Christ – preaching the Gospel to the pagans. We note the following symbols of spiritual life: community life – the monk’s habit, golden solitude – the hermitage, preaching the Gospel to the pagans – martyrdom. According to established monastic tradition, before becoming a hermit it is necessary to pass through the stage of community life. The Rule of St. Benedict states that the hermits are ‘no longer in the first fervour of their reformation, but after long probation in a monastery, having learned by the help of many brethren how to fight against the devil, go out well armed from the ranks of the community to the solitary combat of the desert. They are able now, with no help save from God, to fight single-handed against the vices of the flesh and their own evil thoughts’. The second component of his life is his time as a hermit. For some while St Bruno followed the teaching of St. Romuald, who provided a rule for hermits. First of all, he offered them St. Benedict’s Rule, but the Life of the Five Brethren includes the so-called ‘Little Rule’, which describes the ideal hermit life compactly. The third component is preaching the Gospel – martyrdom. St. Bruno keeps mentioning two things: the preaching of the Gospel and martyrdom. It is thought that his primary goal was martyrdom, and he understood the preaching of the Gospel as a method to attain this goal. With complete sacrifice he begins to preach the Gospel to the pagan nations until finally in 1009 he meets a martyr’s death on the border of Lithuania and Rus’.
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WICHAIDIT, Sujira, Praneed SONGWATHANA, Karnsunaphat BALTHIP, and Martin WOODS. "Healing Strategies among Thai Buddhist Widows after Sudden of Loss of Spouse in Terrorist Attacks." Walailak Journal of Science and Technology (WJST) 16, no. 4 (July 9, 2018): 243–54. http://dx.doi.org/10.48048/wjst.2019.4051.
Full textAbstract:
Background: Both physical and psychological suffering among women after the loss of their husband as a result of traumatic events has been evident. However, little is known about the strategies used by Thai widows who are able to heal and return to normal living in areas of unrest.Objectives: The purpose of this study is to describe the healing strategies used by Thai Buddhist widows to heal their suffering from the sudden loss of their spouse in terrorist attacks.Methodology: This is a primary analysis of data generated from a qualitative study of Thai Buddhist widows who lost their spouse because of terrorist attacks in the southernmost provinces of Thailand. Five Buddhist widows were purposively selected to participate in the study, using in-depth interviews and observation for data collection. Content analysis was employed as part of the data analysis to identify and describe the strategies used by the selected participants.Results: The participants were aged between 37 and 64 years old and had experienced the loss of a spouse within the previous 2 to 10 years. They had been successful in healing their suffering. Several strategies had been used, with initial support and assistance from families and close friends. Firstly, as per the Buddhist belief system, ‘merit making’, such as praying, practicing meditation, or offering money and/or food to monks, was often performed by the women. These practices helped them to ease their anxiety about their husbands’ afterlife happiness and whether or not they were living in a good place. Secondly, venting their feelings and emotions with family and close friends, including talking to their husband’s picture, provided some suffering relief. Lastly, a deep understanding of Dukkha (suffering) and the natural law of life in Buddhism helped widows to realize the right ways to create a positive mindset and new future life.Conclusions/Recommendations: The strategies used to heal themselves from suffering by Thai Buddhist widows could be of benefit for nurses, to enable them to develop interventions that not only relieve human suffering from the unexpected loss of loved ones, but also promote mental health through healing and spiritual growth in their own lives.