Journal articles: 'Hemispheric interactions'

1

Hartikainen, Kaisa M. "Emotion-Attention Interaction in the Right Hemisphere." Brain Sciences 11, no. 8 (July 29, 2021): 1006. http://dx.doi.org/10.3390/brainsci11081006.

Full text

Abstract:

Hemispheric asymmetries in affective and cognitive functions have been extensively studied. While both cerebral hemispheres contribute to most affective and cognitive processes, neuroscientific literature and neuropsychological evidence support an overall right hemispheric dominance for emotion, attention and arousal. Emotional stimuli, especially those with survival value such as threat, tend to be prioritized in attentional resource competition. Arousing unpleasant emotional stimuli have prioritized access, especially to right-lateralized attention networks. Interference of task performance may be observed when limited resources are exhausted by task- and emotion-related processing. Tasks that rely on right hemisphere-dependent processing, like attending to the left visual hemifield or global-level visual features, are especially vulnerable to interference due to attention capture by unpleasant emotional stimuli. The aim of this review is to present literature regarding the special role of the right hemisphere in affective and attentional brain processes and their interaction. Furthermore, clinical and technological implications of this interaction will be presented. Initially, the effects of focal right hemisphere lesion or atrophy on emotional functions will be introduced. Neurological right hemisphere syndromes including aprosodia, anosognosia and neglect, which further point to the predominance of the intact right hemisphere in emotion, attention and arousal will be presented. Then there will be a brief review of electrophysiological evidence, as well as evidence from patients with neglect that support attention capture by emotional stimuli in the right hemisphere. Subsequently, experimental work on the interaction of emotion, attention and cognition in the right hemispheres of healthy subjects will be presented. Finally, clinical implications for better understanding and assessment of alterations in emotion–attention interaction due to brain disorder or treatment, such as neuromodulation, that impact affective brain functions will be discussed. It will be suggested that measuring right hemispheric emotion–attention interactions may provide basis for novel biomarkers of brain health. Such biomarkers allow for improved diagnostics in brain damage and disorders and optimized treatments. To conclude, future technological applications will be outlined regarding brain physiology-based measures that reflect engagement of the right hemisphere in affective and attentional processes.

APA, Harvard, Vancouver, ISO, and other styles

2

METUKI, NILI, SHANI SINKEVICH, and MICHAL LAVIDOR. "Lateralization of semantic processing is shaped by exposure to specific mother tongues: The case of insight problem solving by bilingual and monolingual native Hebrew speakers." Bilingualism: Language and Cognition 16, no. 4 (February 15, 2013): 900–913. http://dx.doi.org/10.1017/s1366728913000023.

Full text

Abstract:

Solving insight problems is a complex task found to involve coarse semantic processing in the right hemisphere when tested in English. In Hebrew, the left hemisphere (LH) may be more active in this task, due to the inter-hemispheric interaction between semantic, phonological and orthographic processing. In two Hebrew insight problems experiments, we revealed a performance advantage in the LH, in contrast to the patterns previously observed in English. A third experiment, conducted in English with early Hebrew–English bilinguals, confirmed that the LH advantage found with Hebrew speakers does not depend on specific task requirements in Hebrew. We suggest that Hebrew speakers show redundancy between the hemispheres in coarse semantic processing in handling frequent lexical ambiguities stemming from the orthographic structure in Hebrew. We further suggest that inter-hemispheric interactions between linguistic and non-linguistic processes may determine the hemisphere in which coarse coding will take place. These findings highlight the possible effect of exposure to a specific mother tongue on the lateralization of processes in the brain, and carries possible theoretical and methodological implications for cross-language studies.

APA, Harvard, Vancouver, ISO, and other styles

3

Rastatter, Michael P., and Andrew Stuart. "Hemispheric Picture-Naming Hierarchies in Stuttering Subjects." Perceptual and Motor Skills 81, no. 3 (December 1995): 899–908. http://dx.doi.org/10.2466/pms.1995.81.3.899.

Full text

Abstract:

The present study was done to investigate the linguistic organization of the right hemisphere of stuttering subjects and the interhemispheric interactions that underlie verbal output in this population. Naming reaction times of 14 stuttering adults were measured to unilaterally presented pictures corresponding to vocabulary levels of <5.5, 9.5–10.5, and > 18.0 years of age. An analysis of variance of latencies showed a significant main effect for picture vocabulary-age. Post hoc tests were interpreted as suggesting that the right hemisphere of stuttering subjects was capable of differential picture-encoding operations in a manner similar to the left hemisphere of normal speakers. Also, naming latencies favored left visual-field stimulations by 34 msec. Taken with significant and high correlations between visual fields for each level of picture vocabulary score, the right hemispheres of the stuttering subjects appeared responsible for picture-encoding operations. Left-hemispheric stimulus processing was not predicted, suggesting differences may exist in interhemispheric interactions underlying picture-naming functions in stuttering populations.

APA, Harvard, Vancouver, ISO, and other styles

4

Vidal, A. Cristina, Paula Banca, Augusto G. Pascoal, Gustavo C. Santo, João Sargento-Freitas, Ana Gouveia, and Miguel Castelo-Branco. "Bilateral versus ipsilesional cortico-subcortical activity patterns in stroke show hemispheric dependence." International Journal of Stroke 12, no. 1 (October 22, 2016): 71–83. http://dx.doi.org/10.1177/1747493016672087.

Full text

Abstract:

Background Understanding of interhemispheric interactions in stroke patients during motor control is an important clinical neuroscience quest that may provide important clues for neurorehabilitation. In stroke patients, bilateral overactivation in both hemispheres has been interpreted as a poor prognostic indicator of functional recovery. In contrast, ipsilesional patterns have been linked with better motor outcomes. Aim We investigated the pathophysiology of hemispheric interactions during limb movement without and with contralateral restraint, to mimic the effects of constraint-induced movement therapy. We used neuroimaging to probe brain activity with such a movement-dependent interhemispheric modulation paradigm. Methods We used an fMRI block design during which the plegic/paretic upper limb was recruited/mobilized to perform unilateral arm elevation, as a function of presence versus absence of contralateral limb restriction ( n = 20, with balanced left/right lesion sites). Results Analysis of 10 right-hemispheric stroke participants yielded bilateral sensorimotor cortex activation in all movement phases in contrast with the unilateral dominance seen in the 10 left-hemispheric stroke participants. Superimposition of contralateral restriction led to a prominent shift from activation to deactivation response patterns, in particular in cortical and basal ganglia motor areas in right-hemispheric stroke. Left-hemispheric stroke was in general characterized by reduced activation patterns, even in the absence of restriction, which induced additional cortical silencing. Conclusion The observed hemispheric-dependent activation/deactivation shifts are novel and these pathophysiological observations suggest short-term neuroplasticity that may be useful for hemisphere-tailored neurorehabilitation.

APA, Harvard, Vancouver, ISO, and other styles

5

Sakaguchi, Yukitoshi, and Yoshio Sakurai. "Disconnection between Rat’s Left and Right Hemisphere Impairs Short-Term Memory but Not Long-Term Memory." Symmetry 13, no. 10 (October 4, 2021): 1872. http://dx.doi.org/10.3390/sym13101872.

Full text

Abstract:

Split-brain experiments, which have been actively conducted since the twentieth century, have provided a great deal of insight into functional asymmetry and inter-hemispheric interactions. However, how communication between the left and right hemispheres directly contributes to memory formation is still poorly understood. To address this issue, we cut the rat commissural fibers prior to performing behavioral tests, which consisted of two short-term and two long-term memory tasks. The result showed that cutting the commissural fibers impairs short-term memory but not long-term memory. This suggests that the left-right hemispheric interaction through the commissural fibers contributes to the appropriate formation of short-term memory, but not that of long-term memory. Our findings would help to elucidate dynamic memory formation between the two hemispheres and contribute to the development of therapeutics for some neurological diseases which cause a reduction in the inter-hemispheric interaction.

APA, Harvard, Vancouver, ISO, and other styles

6

Corballis, M. "Hemispheric interactions in simple reaction time." Neuropsychologia 40, no. 4 (2002): 423–34. http://dx.doi.org/10.1016/s0028-3932(01)00097-5.

Full text

APA, Harvard, Vancouver, ISO, and other styles

7

Banegas, Inmaculada, Isabel Prieto, Ana Belén Segarra, Francisco Vives, Magdalena Martínez-Cañamero, Raquel Durán, Juan de Dios Luna, Marc de Gasparo, Germán Domínguez-Vías, and Manuel Ramírez-Sánchez. "Asymmetric Interaction of Neuropeptidase Activities between Cortico-Limbic Structures, Plasma and Cardiovascular Function after Unilateral Dopamine Depletions of the Nigrostriatal System." Biomedicines 10, no. 2 (January 29, 2022): 326. http://dx.doi.org/10.3390/biomedicines10020326.

Full text

Abstract:

In emotional processing, dopamine (DA) plays an essential role, and its deterioration involves important consequences. Under physiological conditions, dopamine exhibits brain asymmetry and coexists with various neuropeptides that can coordinate the processing of brain functions. Brain asymmetry can extend into a broader concept of asymmetric neurovisceral integration, including behavior. The study of the activity of neuropeptide regulatory enzymes (neuropeptidases, NPs) is illustrative. We have observed that the left and right brain areas interact intra- and inter-hemispherically, as well as with peripheral tissues or with physiological parameters such as blood pressure or with behaviors such as turning preference. To obtain data that reflect this integrative behavior, we simultaneously analyzed the impact of left or right brain DA depletion on the activity of various NPs in corticolimbic regions of the left and right hemispheres, such as the medial prefrontal cortex, amygdala and hippocampus, as well as on the plasma activity of the same aminopeptidase activities (APs) and on systolic blood pressure (SBP). Intra- and inter-hemispheric interactions as well as the interactions of NPs from the left or right hemispheres were analyzed with the same plasma APs and the SBP obtained from sham and from left or right lesioned rats. The results demonstrate a complex profile depending on the hemisphere considered. They definitively confirm an asymmetric neurovisceral integration and reveal a higher level of inter-hemispheric corticolimbic interactions including with SBP after left dopamine depletion.

APA, Harvard, Vancouver, ISO, and other styles

8

Mathur, Rohit, Jia Xing, Robert Gilliam, Golam Sarwar, Christian Hogrefe, Jonathan Pleim, George Pouliot, et al. "Extending the Community Multiscale Air Quality (CMAQ) modeling system to hemispheric scales: overview of process considerations and initial applications." Atmospheric Chemistry and Physics 17, no. 20 (October 19, 2017): 12449–74. http://dx.doi.org/10.5194/acp-17-12449-2017.

Full text

Abstract:

Abstract. The Community Multiscale Air Quality (CMAQ) modeling system is extended to simulate ozone, particulate matter, and related precursor distributions throughout the Northern Hemisphere. Modeled processes were examined and enhanced to suitably represent the extended space and timescales for such applications. Hemispheric-scale simulations with CMAQ and the Weather Research and Forecasting (WRF) model are performed for multiple years. Model capabilities for a range of applications including episodic long-range pollutant transport, long-term trends in air pollution across the Northern Hemisphere, and air pollution–climate interactions are evaluated through detailed comparison with available surface, aloft, and remotely sensed observations. The expansion of CMAQ to simulate the hemispheric scales provides a framework to examine interactions between atmospheric processes occurring on various spatial and temporal scales with physical, chemical, and dynamical consistency.

APA, Harvard, Vancouver, ISO, and other styles

9

Chen, Qunlin, Yunman Xia, Kaixiang Zhuang, Xinran Wu, Guangyuan Liu, and Jiang Qiu. "Decreased inter-hemispheric interactions but increased intra-hemispheric integration during typical aging." Aging 11, no. 22 (November 21, 2019): 10100–10115. http://dx.doi.org/10.18632/aging.102421.

Full text

APA, Harvard, Vancouver, ISO, and other styles

10

Saenko, I. V., L. A. Chernikova, A. E. Khizhnikova, E. I. Kremneva, and I. B. Kozlovskaya. "DYNAMICS OF THE PROCESSES OF INTER- AND INTRA-HEMISPHERIC INTERACTIONS (FUNCTIONAL CONNECTIVITY) OF THE BRAIN MOTOR ZONES RESPONSIBLE FOR WALKING IN NEURO-REHABILITATION OF PATIENTS WITH FOCAL DAMAGES OF THE CENTRAL NERVOUS SYSTEM." Aerospace and Environmental Medicine 54, no. 6 (2020): 136–43. http://dx.doi.org/10.21687/0233-528x-2020-54-6-136-143.

Full text

Abstract:

The paper discusses the findings of studying neuroplastic transformations in the brain cortex owing to stroke patients therapy using soft multimodel exoskeleton complex (MEC) REGENT in comparison with activation of the cortex structures controlling locomotion in healthy people. The MEC course applied to hemiparetic patients increases walk speed; changes in the activity zones detected by functional magnetic resonance imaging (fMRI) attest to the positive trajectory of neuroplastic processes, i.e. activation in the precentral gyrus (primary motor cortex), secondary association cortex (inferior parietal lobule) on the damaged hemisphere, and right-side primary sensorimotor cortex. Analysis of the functional connectivity between the areas of interest before and after the MEC therapy elicited significant changes in the inter- and intra-hemispheric connections. This positive cortical reorganization has its origin in reduction of excitory interactions between the secondary associative areas (inferior parietal lobules in both hemispheres) and alleviation of the inhibitory interaction between the inferior parietal lobule and primary right-side sensorimotor cortex in the damaged hemisphere.

APA, Harvard, Vancouver, ISO, and other styles

11

Chang, Edmund K. M. "The Role of Wave Packets in Wave–Mean Flow Interactions during Southern Hemisphere Summer." Journal of the Atmospheric Sciences 62, no. 7 (July 1, 2005): 2467–83. http://dx.doi.org/10.1175/jas3491.1.

Full text

Abstract:

Abstract In this study, reanalysis data produced by the European Centre for Medium-Range Weather Forecasts for 14 Southern Hemisphere (SH) summer seasons have been analyzed. All cases of hemispheric transient eddy kinetic energy (TEKE) maxima have been identified, and the evolution of the local energetics and planetary-scale flow anomalies accompanying these TEKE growth/decay episodes are composited. The longitude–time evolution of the composite energetics shows the clear signature of a wave packet propagating eastward at a group velocity of about 27° longitude per day and undergoing a life cycle of growth and decay, with the energetics within a volume close to the wave packet center dominating the hemispheric mean energetics. When individual cases are examined, 52% are found to resemble the composite and have the energetics life cycle dominated by the evolution of a single wave packet, and an additional 21% are found to be dominated by the evolution of two wave packets having similar amplitudes. Only the remaining 27% can be regarded as having experienced TEKE growth and decay throughout much of the hemisphere. The zonal mean flow and eddy feedback anomalies (i.e., reduction in the meridional temperature gradient due to the effects of the eddy heat fluxes, as well as increase in the barotropic shear due to a narrowing of the midlatitude jet through the effects of the eddy momentum fluxes) associated with the cases dominated by the evolution of a single wave packet are also found to be dominated by anomalies close to the wave packet center. The fact that hemispheric wave growth/decay is often dominated by the evolution of a single wave packet has interesting dynamical consequences when the climatological basic flow is not zonally symmetric. When a wave packet propagates over regions of enhanced baroclinicity, it can extract more energy from the mean flow via baroclinic conversion, leading to its preferential growth. On the other hand, when a wave packet propagates over regions of weak baroclinicity, baroclinic conversion is suppressed; hence any packet growth must be due to other processes. By examining the location of wave packet peaks when hemispheric TEKE is at a maximum, it is observed that hemispheric mean TEKE peaks much more frequently when the dominant wave packet is located downstream of the region with strongest baroclinicity. In addition, the growth in TEKE for these cases is usually dominated by an increase in baroclinic conversion. In contrast, for the small number of cases in which the hemispheric mean TEKE maximum occurs when the dominant wave packet is located downstream of the region with weakest baroclinicity, the growth of the hemispheric TEKE is instead dominated by a reduction in barotropic dissipation.

APA, Harvard, Vancouver, ISO, and other styles

12

McCoy, Isabel L., Daniel T. McCoy, Robert Wood, Leighton Regayre, Duncan Watson-Parris, Daniel P. Grosvenor, Jane P. Mulcahy, et al. "The hemispheric contrast in cloud microphysical properties constrains aerosol forcing." Proceedings of the National Academy of Sciences 117, no. 32 (July 27, 2020): 18998–9006. http://dx.doi.org/10.1073/pnas.1922502117.

Full text

Abstract:

The change in planetary albedo due to aerosol−cloud interactions during the industrial era is the leading source of uncertainty in inferring Earth’s climate sensitivity to increased greenhouse gases from the historical record. The variable that controls aerosol−cloud interactions in warm clouds is droplet number concentration. Global climate models demonstrate that the present-day hemispheric contrast in cloud droplet number concentration between the pristine Southern Hemisphere and the polluted Northern Hemisphere oceans can be used as a proxy for anthropogenically driven change in cloud droplet number concentration. Remotely sensed estimates constrain this change in droplet number concentration to be between 8 cm−3and 24 cm−3. By extension, the radiative forcing since 1850 from aerosol−cloud interactions is constrained to be −1.2 W⋅m−2to −0.6 W⋅m−2. The robustness of this constraint depends upon the assumption that pristine Southern Ocean droplet number concentration is a suitable proxy for preindustrial concentrations. Droplet number concentrations calculated from satellite data over the Southern Ocean are high in austral summer. Near Antarctica, they reach values typical of Northern Hemisphere polluted outflows. These concentrations are found to agree with several in situ datasets. In contrast, climate models show systematic underpredictions of cloud droplet number concentration across the Southern Ocean. Near Antarctica, where precipitation sinks of aerosol are small, the underestimation by climate models is particularly large. This motivates the need for detailed process studies of aerosol production and aerosol−cloud interactions in pristine environments. The hemispheric difference in satellite estimated cloud droplet number concentration implies preindustrial aerosol concentrations were higher than estimated by most models.

APA, Harvard, Vancouver, ISO, and other styles

13

Wu, Xia, Yan Zhang, Maojie Guo, Yunpeng Jiang, and Xiaozhuang Wang. "The Lateralization of Attentional Functions in Action Video Game Players." Experimental Psychology 68, no. 4 (July 2021): 198–205. http://dx.doi.org/10.1027/1618-3169/a000522.

Full text

Abstract:

Abstract. Action video game players (AVGPs) are proven to be significantly different from non-AVGPs (NAVGPs) in attention, which is proposed to be divided into three functional networks: alerting, orienting, and execution control. However, whether the hemispheric lateralization of attentional functions is influenced by the action video game is unclear. In the present study, we examined the lateralization of the three attentional functions in a group of AVGPs ( n = 33) compared to NAVGPs ( n = 34). The results showed that, relative to NAVGPs, the interactions between orienting and executive control in the left hemispheres of AVGPs were higher than those in the right hemisphere. Moreover, the correlations among the functions are much more sensitive in the left hemisphere. These results suggest significant left lateralization of the attentional functions in AVGPs.

APA, Harvard, Vancouver, ISO, and other styles

14

Cherbuin, Nicolas, and Cobie Brinkman. "Hemispheric interactions are different in left-handed individuals." Neuropsychology 20, no. 6 (2006): 700–707. http://dx.doi.org/10.1037/0894-4105.20.6.700.

Full text

APA, Harvard, Vancouver, ISO, and other styles

15

Norman, W. D., M. A. Jeeves, A. Milne, and T. Ludwig. "Hemispheric interactions: The Bilateral Advantage and Task Difficulty." Cortex 28, no. 4 (December 1992): 623–42. http://dx.doi.org/10.1016/s0010-9452(13)80231-6.

Full text

APA, Harvard, Vancouver, ISO, and other styles

16

Ramon, Dan, Yonit Doron, and Miriam Faust. "Categorization and affect: Evidence for intra-hemispheric interactions." Brain and Cognition 63, no. 3 (April 2007): 296–303. http://dx.doi.org/10.1016/j.bandc.2006.09.012.

Full text

APA, Harvard, Vancouver, ISO, and other styles

17

Takeuchi, Naoyuki, Yutaka Oouchida, and Shin-Ichi Izumi. "Motor Control and Neural Plasticity through Interhemispheric Interactions." Neural Plasticity 2012 (2012): 1–13. http://dx.doi.org/10.1155/2012/823285.

Full text

Abstract:

The corpus callosum, which is the largest white matter structure in the human brain, connects the 2 cerebral hemispheres. It plays a crucial role in maintaining the independent processing of the hemispheres and in integrating information between both hemispheres. The functional integrity of interhemispheric interactions can be tested electrophysiologically in humans by using transcranial magnetic stimulation, electroencephalography, and functional magnetic resonance imaging. As a brain structural imaging, diffusion tensor imaging has revealed the microstructural connectivity underlying interhemispheric interactions. Sex, age, and motor training in addition to the size of the corpus callosum influence interhemispheric interactions. Several neurological disorders change hemispheric asymmetry directly by impairing the corpus callosum. Moreover, stroke lesions and unilateral peripheral impairments such as amputation alter interhemispheric interactions indirectly. Noninvasive brain stimulation changes the interhemispheric interactions between both motor cortices. Recently, these brain stimulation techniques were applied in the clinical rehabilitation of patients with stroke by ameliorating the deteriorated modulation of interhemispheric interactions. Here, we review the interhemispheric interactions and mechanisms underlying the pathogenesis of these interactions and propose rehabilitative approaches for appropriate cortical reorganization.

APA, Harvard, Vancouver, ISO, and other styles

18

Ciechanski, Patrick, Ephrem Zewdie, and Adam Kirton. "Developmental profile of motor cortex transcallosal inhibition in children and adolescents." Journal of Neurophysiology 118, no. 1 (July 1, 2017): 140–48. http://dx.doi.org/10.1152/jn.00076.2017.

Full text

Abstract:

Transcallosal fibers facilitate interhemispheric networks involved in motor tasks. Despite their clinical relevance, interhemispheric motor control systems have not been completely defined in the developing brain. The objective of this study was to examine the developmental profile of transcallosal inhibition in healthy children and adolescents. Nineteen typically developing right-handed participants were recruited. Two transcranial magnetic stimulation (TMS) paradigms assessed transcallosal inhibition: ipsilateral silent periods (iSP) and paired-pulse interhemispheric inhibition (IHI). TMS was applied to the motor hotspot of the first dorsal interosseous muscle. Resting motor threshold (RMT), iSP latency, duration and suppression strength, and paired-pulse IHI were measured from both hemispheres. The Purdue Pegboard Test assessed unimanual motor function. Hemispheric differences were evident for RMT and iSP latency and suppression strength, where the left hemisphere had a lower RMT, prolonged latency, and greater suppression strength. iSP duration showed hemispheric symmetry. RMT and iSP latency decreased with age, whereas iSP suppression strength increased. Girls showed shorter iSP latency. Children typically displayed IHI, although hemispheric differences were observed. iSP suppression strength was uniquely associated with IHI within individuals. iSP duration correlated with motor performance. TMS can characterize transcallosal inhibition in normal children and adolescents with effects of age, directionality, sex, and motor performance. Establishing this developmental profile of interhemispheric interactions may advance understanding and therapeutic strategies for pediatric motor disorders such as cerebral palsy. NEW & NOTEWORTHY Here we demonstrate that transcranial magnetic stimulation can characterize transcallosal inhibition in normal children and adolescents with effects of age, directionality, handedness, and motor performance. Interestingly, we also demonstrated sex effects, possibly related to the differing developmental profiles of boys and girls. Establishing this developmental profile of interhemispheric interactions may advance understanding and therapeutic strategies for pediatric motor disorders such as cerebral palsy.

APA, Harvard, Vancouver, ISO, and other styles

19

Giljov, Andrey, Karina Karenina, and Yegor Malashichev. "Facing each other: mammal mothers and infants prefer the position favouring right hemisphere processing." Biology Letters 14, no. 1 (January 2018): 20170707. http://dx.doi.org/10.1098/rsbl.2017.0707.

Full text

Abstract:

The right hemisphere plays a crucial role in social processing. Human mothers show a robust left cradling/holding bias providing greater right-hemispheric involvement in the exchange of social information between mother and infant. Here, we demonstrate that a similar bias is evident in face-to-face spatial interactions in marine and terrestrial non-primate mammals. Walruses and Indian flying foxes showed a significant population-level preference for the position which facilitates the use of the left visual field in both mother and infant. This behavioural lateralization may have emerged owing to benefits conferred by the enhanced right-hemispheric social processing providing the mother and infant an optimal perception of each other.

APA, Harvard, Vancouver, ISO, and other styles

20

Corballis, Michael C. "Hemispheric interactions in temporal judgments about spatially separated stimuli." Neuropsychology 10, no. 1 (1996): 42–50. http://dx.doi.org/10.1037/0894-4105.10.1.42.

Full text

APA, Harvard, Vancouver, ISO, and other styles

21

Kavcic, Voyko, and Jeffrey M. Clarke. "Hemispheric interactions during a face–word Stroop-analog task." Neuropsychology 14, no. 4 (2000): 579–87. http://dx.doi.org/10.1037/0894-4105.14.4.579.

Full text

APA, Harvard, Vancouver, ISO, and other styles

22

Chung, Eui-Seok, and Brian J. Soden. "Hemispheric climate shifts driven by anthropogenic aerosol–cloud interactions." Nature Geoscience 10, no. 8 (July 17, 2017): 566–71. http://dx.doi.org/10.1038/ngeo2988.

Full text

APA, Harvard, Vancouver, ISO, and other styles

23

Hugdahl, Kenneth, Sara Saban, Bjørn Helge Johnsen, and Claes Göran Brobeck. "Hemispheric asymmetry and human associative learning: Interactions with attention." Integrative Physiological and Behavioral Science 29, no. 1 (January 1994): 25–38. http://dx.doi.org/10.1007/bf02691279.

Full text

APA, Harvard, Vancouver, ISO, and other styles

24

Ratinckx, Elie, Marc Brysbaert, and Bert Reynvoet. "Bilateral field interactions and hemispheric asymmetry in number comparison." Neuropsychologia 39, no. 4 (January 2001): 335–45. http://dx.doi.org/10.1016/s0028-3932(00)00143-3.

Full text

APA, Harvard, Vancouver, ISO, and other styles

25

Prete, Giulia, Daniele Marzoli, and Luca Tommasi. "Upright or inverted, entire or exploded: right-hemispheric superiority in face recognition withstands multiple spatial manipulations." PeerJ 3 (December 1, 2015): e1456. http://dx.doi.org/10.7717/peerj.1456.

Full text

Abstract:

Background.The ability to identify faces has been interpreted as a cerebral specialization based on the evolutionary importance of these social stimuli, and a number of studies have shown that this function is mainly lateralized in the right hemisphere. The aim of this study was to assess the right-hemispheric specialization in face recognition in unfamiliar circumstances.Methods.Using a divided visual field paradigm, we investigated hemispheric asymmetries in the matching of two subsequent faces, using two types of transformation hindering identity recognition, namely upside-down rotation and spatial “explosion” (female and male faces were fractured into parts so that their mutual spatial relations were left intact), as well as their combination.Results.We confirmed the right-hemispheric superiority in face processing. Moreover, we found a decrease of the identity recognition for more extreme “levels of explosion” and for faces presented upside-down (either as sample or target stimuli) than for faces presented upright, as well as an advantage in the matching of female compared to male faces.Discussion.We conclude that the right-hemispheric superiority for face processing is not an epiphenomenon of our expertise, because we are not often exposed to inverted and “exploded” faces, but rather a robust hemispheric lateralization. We speculate that these results could be attributable to the prevalence of right-handedness in humans and/or to early biases in social interactions.

APA, Harvard, Vancouver, ISO, and other styles

26

Timmermann, A., M. Latif, R. Voss, and A. Grötzner. "Northern Hemispheric Interdecadal Variability: A Coupled Air–Sea Mode." Journal of Climate 11, no. 8 (August 1, 1998): 1906–31. http://dx.doi.org/10.1175/1520-0442-11.8.1906.

Full text

Abstract:

Abstract A coupled air–sea mode in the Northern Hemisphere with a period of about 35 years is described. The mode was derived from a multicentury integration with a coupled ocean–atmosphere general circulation model and involves interactions of the thermohaline circulation with the atmosphere in the North Atlantic and interactions between the ocean and the atmosphere in the North Pacific. The authors focus on the physics of the North Atlantic interdecadal variability. If, for instance, the North Atlantic thermohaline circulation is anomalously strong, the ocean is covered by positive sea surface temperature (SST) anomalies. The atmospheric response to these SST anomalies involves a strengthened North Atlantic Oscillation, which leads to anomalously weak evaporation and Ekman transport off Newfoundland and in the Greenland Sea, and the generation of negative sea surface salinity (SSS) anomalies. These SSS anomalies weaken the deep convection in the oceanic sinking regions and subsequently the strength of the thermohaline circulation. This leads to a reduced poleward heat transport and the formation of negative SST anomalies, which completes the phase reversal. The Atlantic and Pacific Oceans seem to be coupled via an atmospheric teleconnection pattern and the interdecadal Northern Hemispheric climate mode is interpreted as an inherently coupled air–sea mode. Furthermore, the origin of the Northern Hemispheric warming observed recently is investigated. The observed temperatures are compared to a characteristic warming pattern derived from a greenhouse warming simulation with the authors’ coupled general circulation model and also with the Northern Hemispheric temperature pattern associated with the 35-yr climate mode. It is shown that the recent Northern Hemispheric warming projects well onto the temperature pattern of the interdecadal mode under consideration.

APA, Harvard, Vancouver, ISO, and other styles

27

Levitan, Svetlana, and James A. Reggia. "A Computational Model of Lateralization and Asymmetries in Cortical Maps." Neural Computation 12, no. 9 (September 1, 2000): 2037–62. http://dx.doi.org/10.1162/089976600300015051.

Full text

Abstract:

While recent experimental work has defined asymmetries and lateralization in left and right cortical maps, the mechanisms underlying these phenomena are currently not established. In order to explore some possible mechanisms in theory, we studied a neural model consisting of paired cerebral hemispheric regions interacting via a simulated corpus callosum. Starting with random synaptic strengths, unsupervised (Hebbian) synaptic modifications led to the emergence of a topographic map in one or both hemispheric regions. Because of uncertainties concerning the nature of hemispheric interactions, both excitatory and inhibitory callosal influences were examined independently. A sharp transition in model behavior was observed depending on callosal strength. For excitatory or weakly inhibitory callosal interactions, complete and symmetric mirror-image maps generally appeared in both hemispheric regions. In contrast, with stronger inhibitory callosal interactions, partial to complete map lateralization tended to occur, and the maps in each hemispheric region often became complementary. Lateralization occurred readily toward the side having a larger cortical region or higher excitability. Asymmetric synaptic plasticity, however, had only a transitory effect on lateralization. These results support the hypotheses that interhemispheric competition occurs, that multiple underlying asymmetries may lead to function lateralization, and that the effects of asymmetric synaptic plasticity may vary depending on whether supervised or unsupervised learning is involved. To our knowledge, this is the first computational model to demonstrate the emergence of topographic map lateralization and asymmetries.

APA, Harvard, Vancouver, ISO, and other styles

28

Fudin, Robert. "Re-Examination of Evidence Questions Christman's (1989) Report of Moderate Experimental Support for the Visual Spatial Frequency Hypothesis." Perceptual and Motor Skills 80, no. 3 (June 1995): 955–62. http://dx.doi.org/10.2466/pms.1995.80.3.955.

Full text

Abstract:

The visual spatial frequency hypothesis contends that perceptual characteristics of stimulus arrays can affect the magnitude and direction of hemispheric asymmetries in laterality experiments. In a 1989 literature review, Christman reported that 45 of 79 experimental comparisons yielded significant interactions for side of hemispheric advantage x perceptual characteristic which supported the visual spatial frequency hypothesis, a level of support he characterized as moderate. Re-examination of those 45 outcomes shows that in 20 of them either a significant interaction for side of hemispheric advantage x perceptual characteristic was not found or, if it was, the particulars do not agree fully with predictions of the visual spatial frequency hypothesis as presented by Christman in the 1989 paper. These findings suggest that experimental support for the visual spatial frequency hypothesis is weak, not moderate as characterized by Christman.

APA, Harvard, Vancouver, ISO, and other styles

29

Morais, Jose, and Elisabetta Ladavas. "Hemispheric Interactions in the Recognition of Words and Emotional Intonations." Cognition & Emotion 1, no. 1 (March 1987): 89–100. http://dx.doi.org/10.1080/02699938708408365.

Full text

APA, Harvard, Vancouver, ISO, and other styles

30

Wiedermann, Marc, Jonathan F. Donges, Dörthe Handorf, Jürgen Kurths, and Reik V. Donner. "Hierarchical structures in Northern Hemispheric extratropical winter ocean-atmosphere interactions." International Journal of Climatology 37, no. 10 (December 26, 2016): 3821–36. http://dx.doi.org/10.1002/joc.4956.

Full text

APA, Harvard, Vancouver, ISO, and other styles

31

LYBBERT, TRAVIS J., AARON SMITH, and DANIEL A. SUMNER. "WEATHER SHOCKS AND INTER-HEMISPHERIC SUPPLY RESPONSES: IMPLICATIONS FOR CLIMATE CHANGE EFFECTS ON GLOBAL FOOD MARKETS." Climate Change Economics 05, no. 04 (December 2014): 1450010. http://dx.doi.org/10.1142/s2010007814500109.

Full text

Abstract:

Climate models predict more weather extremes in the coming decades. Weather shocks can directly reduce crop production, but their effect on food markets is partly buffered by storage and supply responses that can be complex and nuanced. We explore how inter-hemispheric trade and supply responses can moderate the effects of weather shocks on global food supply by enabling potential intra-annual arbitrage. Our estimates of this effect in the case of wheat and soybeans suggest that it may be considerable: 25–50% of crop production lost to a shock in the Southern Hemisphere is offset six months later by increased production in the North. These results have implications for the potential effects of climate change on global food markets, for how we model these interactions and, possibly, for the design of trade and production-related policies that aim to leverage this inter-hemispheric buffer more effectively.

APA, Harvard, Vancouver, ISO, and other styles

32

Van Kaam, Ruud C., Michel J. A. M. van Putten, Sarah E. Vermeer, and Jeannette Hofmeijer. "Contralesional Brain Activity in Acute Ischemic Stroke." Cerebrovascular Diseases 45, no. 1-2 (2018): 85–92. http://dx.doi.org/10.1159/000486535.

Full text

Abstract:

Background: The noninjured, contralateral hemisphere is increasingly acknowledged in the process of recovery from acute ischemic stroke. We estimated the value of conventional electroencephalography (EEG) recordings for identifying contralateral hemisphere involvement in relation to functional recovery. Methods: We analyzed 2-min epochs from 21 electrode EEG registrations of 18 patients with acute hemispheric ischemic stroke and compared with 18 age-matched controls. Outcome was dichotomized as good (modified Rankin Scale [mRS] 0–2) or poor (mRS 3–5 or death) at 3 months. Effects of the infarct on the ipsi-and contralateral hemispheres were analyzed by the delta/alpha ratio (DAR) and 2 measures of functional connectivity (magnitude squared coherence [MSC] and weighted phase lag index [WPLI]). Results: DAR was higher in patients than in controls, both in the ipsilateral and in the contralateral hemisphere (median 4.5 ± 6.7 ipsilateral and 2.4 ± 2.0 contralateral vs. 0.5 ± 0.5 in the control group, p < 0.001), indicating robust EEG changes in both lesioned and non-lesioned hemisphere. MSC and WPLI in the alpha and beta frequency bands were lower in patients than in controls in both hemispheres, indicating clear disturbances of functional connectivity (p < 0.05). In the poor outcome group, contralateral MSC and WPLI were lower than in the good outcome group, although these differences did not reach statistical significance. Conclusions: Short conventional EEG measurements show robust changes of brain activity and functional connectivity in both ipsilateral and contralateral hemispheres of patients with acute ischemic stroke. Changes of remote functional connectivity tend to interact with functional recovery. Future studies should estimate predictive values for individual patients and interactions with plasticity enhancing treatments.

APA, Harvard, Vancouver, ISO, and other styles

33

FRYE, RICHARD E., BENJAMIN MALMBERG, PAUL SWANK, KAREN SMITH, and SUSAN LANDRY. "Preterm birth and maternal responsiveness during childhood are associated with brain morphology in adolescence." Journal of the International Neuropsychological Society 16, no. 5 (July 8, 2010): 784–94. http://dx.doi.org/10.1017/s1355617710000585.

Full text

Abstract:

AbstractAlthough supportive parenting has been shown to have positive effects on development, the neurobiological basis of supportive parenting has not been investigated. Thirty-three adolescents were systemically selected from a longitudinal study on child development based on maternal responsiveness during childhood, a measure of supportive parenting, and whether they were born term or preterm. We analyzed the effect of preterm birth on hemispheric and regional (frontal, temporal, parietal) cortical thickness and surface area using mixed-model analysis while also considering the effect of brain hemisphere (left vs. right). We then determined whether these factors were moderated by maternal responsiveness during childhood. Preterm birth was associated with regional and hemispheric differences in cortical thickness and surface area. Maternal responsiveness during childhood moderated hemispheric cortical thickness. Adolescence with mothers that were inconsistently responsive during childhood demonstrated greater overall cortical thickness and greater asymmetry in cortical thickness during adolescence as compared to adolescence with mothers who were consistently responsive or unresponsive during childhood. Maternal responsiveness and preterm birth did not interact. These data suggest that changes in brain morphology associated with preterm birth continue into adolescence and support the notion that the style of maternal-child interactions during childhood influence brain development into adolescence. (JINS, 2010, 16, 784–794.)

APA, Harvard, Vancouver, ISO, and other styles

34

Reggia, James A., and Reiner Schulz. "The role of computational modeling in understanding hemispheric interactions and specialization." Cognitive Systems Research 3, no. 1 (March 2002): 87–94. http://dx.doi.org/10.1016/s1389-0417(01)00047-x.

Full text

APA, Harvard, Vancouver, ISO, and other styles

35

Dikaya, L. A., and P. N. Ermakov. "Peculiarities of hemispheric interactions in gifted children with different cognitive orientation." International Journal of Psychophysiology 69, no. 3 (September 2008): 281–82. http://dx.doi.org/10.1016/j.ijpsycho.2008.05.246.

Full text

APA, Harvard, Vancouver, ISO, and other styles

36

B. Larson, Eric, and Warren S. Brown. "Bilateral field interactions, hemispheric specialization and evoked potential interhemispheric transmission time." Neuropsychologia 35, no. 5 (April 1997): 573–81. http://dx.doi.org/10.1016/s0028-3932(96)00099-1.

Full text

APA, Harvard, Vancouver, ISO, and other styles

37

Casagrande, Maria, Francesca Agostini, Francesca Favieri, Giuseppe Forte, Jasmine Giovannoli, Angela Guarino, Andrea Marotta, Fabrizio Doricchi, and Diana Martella. "Age-Related Changes in Hemispherical Specialization for Attentional Networks." Brain Sciences 11, no. 9 (August 24, 2021): 1115. http://dx.doi.org/10.3390/brainsci11091115.

Full text

Abstract:

Many cognitive functions face a decline in the healthy elderly. Within the cognitive domains, both attentional processes and executive functions are impaired with aging. Attention includes three attentional networks, i.e., alerting, orienting, and executive control, showing a hemispheric lateralized pattern in adults. This lateralized pattern could play a role in modulating the efficiency of attentional networks. For these reasons, it could be relevant to analyze the age-related change of the hemispheric specialization of attentional networks. This study aims to clarify this aspect with a lateralized version of the Attentional Network Test for Interaction (ANTI)-Fruit. One hundred seventy-one participants took part in this study. They were divided in three age groups: youth (N = 57; range: 20–30); adults (N = 57; range 31–64), and elderly/older people (N = 57; range: 65–87). The results confirmed the previous outcomes on the efficiency and interactions among attentional networks. Moreover, an age-related generalized slowness was evidenced. These findings also support the hypothesis of a hemispheric asymmetry reduction in elderly/older adults.

APA, Harvard, Vancouver, ISO, and other styles

38

Dima, Mihai, and Gerrit Lohmann. "A Hemispheric Mechanism for the Atlantic Multidecadal Oscillation." Journal of Climate 20, no. 11 (June 1, 2007): 2706–19. http://dx.doi.org/10.1175/jcli4174.1.

Full text

Abstract:

Abstract The physical processes associated with the ∼70-yr period climate mode, known as the Atlantic multidecadal oscillation (AMO), are examined. Based on analyses of observational data, a deterministic mechanism relying on atmosphere–ocean–sea ice interactions is proposed for the AMO. Variations in the thermohaline circulation are reflected as uniform sea surface temperature anomalies in the North Atlantic. These anomalies are associated with a hemispheric wavenumber-1 sea level pressure (SLP) structure in the atmosphere that is amplified through atmosphere–ocean interactions in the North Pacific. The SLP pattern and its associated wind field affect the sea ice export through Fram Strait, the freshwater balance in the northern North Atlantic, and consequently the strength of the large-scale ocean circulation. It generates sea surface temperature anomalies with opposite signs in the North Atlantic and completes a negative feedback. The authors find that the time scale of the cycle is associated with the thermohaline circulation adjustment to freshwater forcing, the SST response to it, the oceanic adjustment in the North Pacific, and the sea ice response to the wind forcing. Finally, it is argued that the Great Salinity Anomaly in the late 1960s and 1970s is part of AMO.

APA, Harvard, Vancouver, ISO, and other styles

39

Hosokawa, K., E. E. Woodfield, M. Lester, S. E. Milan, N. Sato, A. S. Yukimatu, and T. Iyemori. "Interhemispheric comparison of spectral width boundary as observed by SuperDARN radars." Annales Geophysicae 21, no. 7 (July 31, 2003): 1553–65. http://dx.doi.org/10.5194/angeo-21-1553-2003.

Full text

Abstract:

Abstract. Previous studies have shown that dayside equatorward edge of coherent HF radar backscatter having broad Doppler spectral width is coincident with the equatorward edge of the cusp particle precipitation. This enables the boundary between broad and narrow spectral width backscatters (spectral width boundary) in the dayside magnetic local time sector to be used as a proxy for the open/closed field line boundary. The present case study employs magnetically conjugate SuperDARN coherent HF radars to make an inter-hemispheric comparison of the location and variation of the spectral width boundaries. Agreement between the magnetic latitudes of the boundaries in both hemispheres is remarkable. Correlation coefficients between the latitudes of the boundaries are larger than 0.70. Temporal variation of the spectral width boundary follows the same equatorward trend in both hemispheres. This is consistent with the accumulation of open flux in the polar cap by dayside low-latitude magnetopause reconnection, expected when IMF Bz is negative. Boundaries in both hemispheres also exhibit short-lived poleward motions superposed on the general equator-ward trend, which follows the onset of substorm expansion phase and a temporary northward excursion of IMF Bz during substorm recovery phase. There is an interhemispheric difference in response time to the substorm occurrence between two hemispheres. The spectral width boundary in the Southern Hemisphere starts to move poleward 10 min earlier than that in the Northern Hemisphere. We discuss this difference in terms of interhemispheric asymmetry of the substorm breakup region in the longitudinal direction associated with the effect of IMF By.Key words. Ionosphere (ionosphere-magnetosphere interactions; plasma convection) – Magnetospheric physics (magnetopause, cusp, boundary layers)

APA, Harvard, Vancouver, ISO, and other styles

40

Thompson, David W. J., Brian R. Crow, and Elizabeth A. Barnes. "Intraseasonal Periodicity in the Southern Hemisphere Circulation on Regional Spatial Scales." Journal of the Atmospheric Sciences 74, no. 3 (March 1, 2017): 865–77. http://dx.doi.org/10.1175/jas-d-16-0094.1.

Full text

Abstract:

Abstract Wave activity in the Southern Hemisphere extratropical atmosphere exhibits robust periodicity on time scales of ~20–25 days. Previous studies have demonstrated the robustness of the periodicity in hemispheric averages of various eddy quantities. Here the authors explore the signature of the periodicity on regional spatial scales. Intraseasonal periodicity in the Southern Hemisphere circulation derives from out-of-phase anomalies in wave activity that form in association with extratropical wave packets as they propagate to the east. In the upper troposphere, the out-of-phase anomalies in wave activity form not along the path of extratropical wave packets, but in their wake. The out-of-phase anomalies in wave activity give rise to periodicity not only on hemispheric scales, but also on synoptic scales when the circulation is sampled along an eastward path between ~5 and 15 m s−1. It is argued that 1) periodicity in extratropical wave activity derives from two-way interactions between the heat fluxes and baroclinicity in the lower troposphere and 2) the unique longitude–time structure of the periodicity in upper-tropospheric wave activity derives from the contrasting eastward speeds of the source of the periodicity in the lower troposphere (~10 m s−1) and wave packets in the upper troposphere (~25 m s−1).

APA, Harvard, Vancouver, ISO, and other styles

41

Roychowdhury, Rajarshi, and Robert DeConto. "Interhemispheric effect of global geography on Earth's climate response to orbital forcing." Climate of the Past 15, no. 1 (February 26, 2019): 377–88. http://dx.doi.org/10.5194/cp-15-377-2019.

Full text

Abstract:

Abstract. The climate response of the Earth to orbital forcing shows a distinct hemispheric asymmetry due to the unequal distribution of land in the Northern Hemisphere versus Southern Hemisphere. This asymmetry is examined using a global climate model (GCM) for different climate responses such as mean summer temperatures and positive degree days. A land asymmetry effect (LAE) is quantified for each hemisphere and the results show how changes in obliquity and precession translate into variations in the calculated LAE. We find that the global climate response to specific past orbits is likely unique and modified by complex climate–ocean–cryosphere interactions that remain poorly known. Nonetheless, these results provide a baseline for interpreting contemporaneous proxy climate data spanning a broad range of latitudes, which may be useful in paleoclimate data–model comparisons, and individual time-continuous records exhibiting orbital cyclicity.

APA, Harvard, Vancouver, ISO, and other styles

42

Persinger, Michael A., Yves R. J. Bureau, Oksana P. Peredery, and Pauline M. Richards. "The Sensed Presence as Right Hemispheric Intrusions into the Left Hemispheric Awareness of Self: An Illustrative Case Study." Perceptual and Motor Skills 78, no. 3 (June 1994): 999–1009. http://dx.doi.org/10.1177/003151259407800358.

Full text

Abstract:

The hypothesis of vectorial hemisphericity predicts that left hemispheric intrusions of the right hemispheric equivalent of the sense of self should be associated with the experience of a “presence” of someone else. The neurophenomenological profile of a woman whose medical history satisfied these theoretical criteria (verified electrical anomalies that could encourage phasic discharges within the right temporal lobe and atrophy within the left temporoparietal region) is presented. In addition to interactions between electrical seizures and thinking, she reported a long history of sensed presences, ego-alien intrusions, and “sudden knowing of the subsequent sequences of seizures” before they occurred clinically. The existence of these neurocognitive processes demands a reevaluation of the psychiatric default explanations of “hysteria” and questions the belief that “awareness during seizures” or “premonition of subsequent somatosensory experience” contraindicates an epileptic process.

APA, Harvard, Vancouver, ISO, and other styles

43

Petrovic, Jelena, Vuk Milosevic, Miroslava Zivkovic, Dragan Stojanov, Olga Milojkovic, Aleksandar Kalauzi, and Jasna Saponjic. "Slower EEG alpha generation, synchronization and “flow”—possible biomarkers of cognitive impairment and neuropathology of minor stroke." PeerJ 5 (September 28, 2017): e3839. http://dx.doi.org/10.7717/peerj.3839.

Full text

Abstract:

Background We investigated EEG rhythms, particularly alpha activity, and their relationship to post-stroke neuropathology and cognitive functions in the subacute and chronic stages of minor strokes. Methods We included 10 patients with right middle cerebral artery (MCA) ischemic strokes and 11 healthy controls. All the assessments of stroke patients were done both in the subacute and chronic stages. Neurological impairment was measured using the National Institute of Health Stroke Scale (NIHSS), whereas cognitive functions were assessed using the Montreal Cognitive Assessment (MoCA) and MoCA memory index (MoCA-MIS). The EEG was recorded using a 19 channel EEG system with standard EEG electrode placement. In particular, we analyzed the EEGs derived from the four lateral frontal (F3, F7, F4, F8), and corresponding lateral posterior (P3, P4, T5, T6) electrodes. Quantitative EEG analysis included: the group FFT spectra, the weighted average of alpha frequency (αAVG), the group probability density distributions of all conventional EEG frequency band relative amplitudes (EEG microstructure), the inter- and intra-hemispheric coherences, and the topographic distribution of alpha carrier frequency phase potentials (PPs). Statistical analysis was done using a Kruskal–Wallis ANOVA with a post-hoc Mann–Whitney U two-tailed test, and Spearman’s correlation. Results We demonstrated transient cognitive impairment alongside a slower alpha frequency (αAVG) in the subacute right MCA stroke patients vs. the controls. This slower alpha frequency showed no amplitude change, but was highly synchronized intra-hemispherically, overlying the ipsi-lesional hemisphere, and inter-hemispherically, overlying the frontal cortex. In addition, the disturbances in EEG alpha activity in subacute stroke patients were expressed as a decrease in alpha PPs over the frontal cortex and an altered “alpha flow”, indicating the sustained augmentation of inter-hemispheric interactions. Although the stroke induced slower alpha was a transient phenomenon, the increased alpha intra-hemispheric synchronization, overlying the ipsi-lesional hemisphere, the increased alpha F3–F4 inter-hemispheric synchronization, the delayed alpha waves, and the newly established inter-hemispheric “alpha flow” within the frontal cortex, remained as a permanent consequence of the minor stroke. This newly established frontal inter-hemispheric “alpha flow” represented a permanent consequence of the “hidden” stroke neuropathology, despite the fact that cognitive impairment has been returned to the control values. All the detected permanent changes at the EEG level with no cognitive impairment after a minor stroke could be a way for the brain to compensate for the lesion and restore the lost function. Discussion Our study indicates slower EEG alpha generation, synchronization and “flow” as potential biomarkers of cognitive impairment onset and/or compensatory post-stroke re-organizational processes.

APA, Harvard, Vancouver, ISO, and other styles

44

Grushin, Alexander, and James A. Reggia. "Evolving processing speed asymmetries and hemispheric interactions in a neural network model." Neurocomputing 65-66 (June 2005): 47–53. http://dx.doi.org/10.1016/j.neucom.2004.10.087.

Full text

APA, Harvard, Vancouver, ISO, and other styles

45

Lee, Sang-Ki, Chunzai Wang, and Brian E. Mapes. "A Simple Atmospheric Model of the Local and Teleconnection Responses to Tropical Heating Anomalies." Journal of Climate 22, no. 2 (January 15, 2009): 272–84. http://dx.doi.org/10.1175/2008jcli2303.1.

Full text

Abstract:

Abstract A minimal complexity model of both the local and remote stationary responses of the atmosphere to tropical heating anomalies is described and demonstrated. Two levels are recast as baroclinic and barotropic components with thermal advection in the tropics neglected. The model is linearized about some idealized and realistic background wind fields and forced with a localized heating for illustration. In the tropics, the baroclinic responses are familiar from the Matsuno–Gill model; these excite barotropic responses by advective interactions with vertical background wind shear. The barotropic signals are in turn transmitted to high latitudes only in the presence of barotropic background westerly winds. For an El Niño–like equatorial heating, the barotropic response has anticyclones to the north and south of the heating reinforcing (opposing) the anticyclonic (cyclonic) baroclinic gyres in the upper (lower) troposphere. With realistic background flows, the model reproduces the hemispheric asymmetry of ENSO teleconnections. Further experiments show that the winter hemisphere is favored mainly because the summer hemispheric subtropical jet is farther from the heating latitude, suggesting that the summer hemisphere can still host robust stationary Rossby waves if the heating occurs in the vicinity of the jet. As an example, it is shown that summer heating over the Atlantic warm pool (AWP) can have a remote influence on the summer climate of North America and Europe.

APA, Harvard, Vancouver, ISO, and other styles

46

Finizio, M., and S. Palmieri. "Non-linear modelling of monthly mean vorticity time changes: an application to the western Mediterranean." Annales Geophysicae 16, no. 1 (January 31, 1998): 116–24. http://dx.doi.org/10.1007/s00585-997-0116-0.

Full text

Abstract:

Abstract. Starting from a number of observables in the form of time-series of meteorological elements in various areas of the northern hemisphere, a model capable of fitting past records and predicting monthly vorticity time changes in the western Mediterranean is implemented. A new powerful statistical methodology is introduced (MARS) in order to capture the non-linear dynamics of time-series representing the available 40-year history of the hemispheric circulation. The developed model is tested on a suitable independent data set. An ensemble forecast exercise is also carried out to check model stability in reference to the uncertainty of input quantities.Key words. Meteorology and atmospheric dynamics · General circulation ocean-atmosphere interactions · Synoptic-scale meteorology

APA, Harvard, Vancouver, ISO, and other styles

47

Petersson, K. M., A. Reis, S. Askelöf, A. Castro-Caldas, and M. Ingvar. "Differences in inter-hemispheric interactions between literate and illiterate subjects during verbal repetition." NeuroImage 7, no. 4 (May 1998): S217. http://dx.doi.org/10.1016/s1053-8119(18)31050-4.

Full text

APA, Harvard, Vancouver, ISO, and other styles

48

Gowani, S. A., J. Barton, M. Levin, and C. Fox. "Prior probability effects and their inter-hemispheric interactions in human prosaccades and antisaccades." Journal of Vision 7, no. 9 (March 18, 2010): 141. http://dx.doi.org/10.1167/7.9.141.

Full text

APA, Harvard, Vancouver, ISO, and other styles

49

Banich, Marie T., and Joel I. Shenker. "Dissociations in memory for item identify and item frequency: Evidence from hemispheric interactions." Neuropsychologia 32, no. 10 (October 1994): 1179–94. http://dx.doi.org/10.1016/0028-3932(94)90101-5.

Full text

APA, Harvard, Vancouver, ISO, and other styles

50

Alloway, Kevin D., Michelle L. Olson, and Jared B. Smith. "Contralateral corticothalamic projections from MI whisker cortex: Potential route for modulating hemispheric interactions." Journal of Comparative Neurology 510, no. 1 (July 9, 2008): 100–116. http://dx.doi.org/10.1002/cne.21782.

Full text

APA, Harvard, Vancouver, ISO, and other styles

Journal articles on the topic 'Hemispheric interactions'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles