Journal articles: 'Timing impairments'

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Ziegler, Wolfram, Erich Hartmann, and Philip Hoole. "Syllabic Timing in Dysarthria." Journal of Speech, Language, and Hearing Research 36, no. 4 (August 1993): 683–93. http://dx.doi.org/10.1044/jshr.3604.683.

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A new, intensity-based method of measuring syllable duration was used to assess syllabic timing in 75 patients with dysarthria of predominantly traumatic and cerebro-vascular origin and in 30 normal subjects. The applied speech tasks included repetitions of sentences containing chains of plosive-vowel-syllables. The logarithm of the duration of the syllable carrying sentence accent proved to be particularly highly correlated with perceived speech rate. Among the potential sources of temporal variability, segmental influences and the influence of sentence stress were examined. Further, the between-sentence variation of syllable duration was assessed. The resulting measures of variability were correlated with the severity of dysarthric impairment. A strengthening of normal effects was found in the consonant-related variation, whereas intrinsic vowel effects and the influence of sentence stress were largely reduced. These results are discussed from the viewpoint of timing theories in speech and limb motor control. They are considered to provide a valuable background against which the speech impairments of specific neurologic groups can be tested.

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Xu, Tongyang, Hedaia Ghannam, and Izzat Darwazeh. "Practical Evaluations of SEFDM: Timing Offset and Multipath Impairments." Infocommunications journal, no. 4 (2018): 2–9. http://dx.doi.org/10.36244/icj.2018.4.1.

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The non-orthogonal signal waveform spectrally efficient frequency division multiplexing (SEFDM) improves spectral efficiency at the cost of self-created inter carrier interference (ICI). As the orthogonal property, similar to orthogonal frequency division multiplexing (OFDM), no longer exists, the robustness of SEFDM in realistic wireless environments might be weakened. This work aims to evaluate the sensitivity of SEFDM to practical channel distortions using a professional experiment testbed. First, timing offset is studied in a bypass channel to locate the imperfection of the testbed and its impact on SEFDM signals. Then, the joint effect of a multipath frequency selective channel and additive white Gaussian noise (AWGN) is investigated in the testbed. Through practical experiments, we demonstrate the performance of SEFDM in realistic radio frequency (RF) environments and verify two compensation methods for SEFDM. Our results show first frequency-domain compensation works well in frequency non-selective channel conditions while time-domain compensation method is suitable for frequency selective channel conditions. This work paves the way for the application of SEFDM in different channel scenarios.

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Vose, Alicia K., Sara Kesneck, Kirstyn Sunday, Emily Plowman, and Ianessa Humbert. "A Survey of Clinician Decision Making When Identifying Swallowing Impairments and Determining Treatment." Journal of Speech, Language, and Hearing Research 61, no. 11 (November 8, 2018): 2735–56. http://dx.doi.org/10.1044/2018_jslhr-s-17-0212.

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Purpose Speech-language pathologists (SLPs) are the primary providers of dysphagia management; however, this role has been criticized with assertions that SLPs are inadequately trained in swallowing physiology (Campbell-Taylor, 2008). To date, diagnostic acuity and treatment planning for swallowing impairments by practicing SLPs have not been examined. We conducted a survey to examine how clinician demographics and swallowing complexity influence decision making for swallowing impairments in videofluoroscopic images. Our goal was to determine whether SLPs' judgments of swallowing timing impairments align with impairment thresholds available in the research literature and whether or not there is agreement among SLPs regarding therapeutic recommendations. Method The survey included 3 videofluoroscopic swallows ranging in complexity (easy, moderate, and complex). Three hundred three practicing SLPs in dysphagia management participated in the survey in a web-based format (Qualtrics, 2005) with frame-by-frame viewing capabilities. SLPs' judgments of impairment were compared against impairment thresholds for swallowing timing measures based on 95% confidence intervals from healthy swallows reported in the literature. Results The primary impairment in swallowing physiology was identified 67% of the time for the easy swallow, 6% for the moderate swallow, and 6% for the complex swallow. On average, practicing clinicians mislabeled 8 or more swallowing events as impaired that were within the normal physiologic range compared with healthy normative data available in the literature. Agreement was higher among clinicians who report using frame-by-frame analysis 80% of the time. A range of 19–21 different treatments was recommended for each video, regardless of complexity. Conclusions Poor to modest agreement in swallowing impairment identification, frequent false positives, and wide variability in treatment planning recommendations suggest that additional research and training in healthy and disordered swallowing are needed to increase accurate dysphagia diagnosis and treatment among clinicians.

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Lense, Miriam D., Eniko Ladányi, Tal-Chen Rabinowitch, Laurel Trainor, and Reyna Gordon. "Rhythm and timing as vulnerabilities in neurodevelopmental disorders." Philosophical Transactions of the Royal Society B: Biological Sciences 376, no. 1835 (August 23, 2021): 20200327. http://dx.doi.org/10.1098/rstb.2020.0327.

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Millions of children are impacted by neurodevelopmental disorders (NDDs), which unfold early in life, have varying genetic etiologies and can involve a variety of specific or generalized impairments in social, cognitive and motor functioning requiring potentially lifelong specialized supports. While specific disorders vary in their domain of primary deficit (e.g. autism spectrum disorder (social), attention-deficit/hyperactivity disorder (attention), developmental coordination disorder (motor) and developmental language disorder (language)), comorbidities between NDDs are common. Intriguingly, many NDDs are associated with difficulties in skills related to rhythm, timing and synchrony though specific profiles of rhythm/timing impairments vary across disorders. Impairments in rhythm/timing may instantiate vulnerabilities for a variety of NDDs and may contribute to both the primary symptoms of each disorder as well as the high levels of comorbidities across disorders. Drawing upon genetic, neural, behavioural and interpersonal constructs across disorders, we consider how disrupted rhythm and timing skills early in life may contribute to atypical developmental cascades that involve overlapping symptoms within the context of a disorder's primary deficits. Consideration of the developmental context, as well as common and unique aspects of the phenotypes of different NDDs, will inform experimental designs to test this hypothesis including via potential mechanistic intervention approaches. This article is part of the theme issue ‘Synchrony and rhythm interaction: from the brain to behavioural ecology’.

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Armstrong, Paul, Marie-Christine Pardon, and Charlotte Bonardi. "Timing impairments in early Alzheimer’s disease: Evidence from a mouse model." Behavioral Neuroscience 134, no. 2 (April 2020): 82–100. http://dx.doi.org/10.1037/bne0000359.

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Dallal, Nancy L., Bin Yin, Tereza Nekovářová, Aleš Stuchlík, and Warren H. Meck. "Impact of Vestibular Lesions on Allocentric Navigation and Interval Timing: The Role of Self-Initiated Motion in Spatial-Temporal Integration." Timing & Time Perception 3, no. 3-4 (December 10, 2015): 269–305. http://dx.doi.org/10.1163/22134468-03002053.

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Bilateral intratympanic sodium arsenate injections (100 mg/ml in isotonic saline) in adult male Long Evans rats produced impairments in allocentric navigation using a 12-arm radial maze procedure as well as a motor test battery designed to evaluate vestibular function. In contrast, no impairments in the accuracy or precision of duration reproduction using 20-s and 80-s peak-interval procedures were observed when both target durations were associated with the same lever response, but distinguished by signal modality (e.g., light or sound). In contrast, an ordinal-reproduction procedure with 800, 3200, and 12,800 ms standards requiring the timing of self-initiated movements during the production phase revealed large impairments in the accuracy and precision of timing for vestibular lesioned rats. These impairments were greater on trials in which self-initiated body movements (e.g., holding down the response lever for a fixed duration) were required without the support of external stimuli signaling the onset and offset of the reproduced duration in contrast to trials in which such external support was provided. The conclusion is that space and time are separable entities and not simply the product of a generalized system, but they can be integrated into a common metric using gravity and self-initiated movement as a reference.

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Sukal-Moulton, Theresa, Kristin J. Krosschell, Deborah J. Gaebler-Spira, and Julius P. A. Dewald. "Motor Impairments Related to Brain Injury Timing in Early Hemiparesis. Part II." Neurorehabilitation and Neural Repair 28, no. 1 (August 2013): 24–35. http://dx.doi.org/10.1177/1545968313497829.

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Beccuti, Guglielmo, Chiara Monagheddu, Andrea Evangelista, Giovannino Ciccone, Fabio Broglio, Laura Soldati, and Simona Bo. "Timing of food intake: Sounding the alarm about metabolic impairments? A systematic review." Pharmacological Research 125 (November 2017): 132–41. http://dx.doi.org/10.1016/j.phrs.2017.09.005.

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Kuper, Willemijn F. E., Claudia van Alfen, Linda van Eck, Barbara C. H. Huijgen, Edward E. S. Nieuwenhuis, Marco van Brussel, and Peter M. van Hasselt. "Motor function impairment is an early sign of CLN3 disease." Neurology 93, no. 3 (June 10, 2019): e293-e297. http://dx.doi.org/10.1212/wnl.0000000000007773.

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ObjectiveTo delineate timing of motor decline in CLN3 disease.MethodsMotor function, assessed by the 6-Minute Walk Test (6MWT), was evaluated repeatedly in 15 patients with CLN3 disease, resulting in 65 test results and during one occasion in 2 control cohorts. One control cohort (n = 14) had isolated visual impairment; a second cohort (n = 12) exhibited visual impairment in combination with neurologic impairments. Based on 6MWT reference values in healthy sighted children, z scores of 6MWT results in patients with CLN3 disease and control cohort individuals were calculated. 6MWT results were correlated with age—including multilevel modeling analysis allowing assessment of imbalanced repeated measurements—and with Unified Batten Disease Rating Scale (UBDRS) scores.ResultsIn CLN3 disease, 6MWT scores were already impaired from first testing near diagnosis (mean z scores of −3.6 and −4.7 at 7 and 8 years of age, respectively). Afterwards, 6MWT scores continuously declined with age (r = −0.64, p < 0.0001) and with increasing UBDRS scores (r = −0.60, p = 0.0001), confirming correlation with disease progression. The decrease was more pronounced at a later age, as shown by the nonlinear multilevel model for 6MWT results in CLN3 disease (y = 409.18 − [0.52 × age2]). In contrast, an upward trend of 6MWT scores with age was observed in the control cohort with isolated visual impairment (r = 0.56; p = 0.04) similar to healthy, sighted children. The control cohort with additional neurologic impairments displayed a slightly decreased 6MWT walking distance independent of age.ConclusionsThe 6MWT unveils early onset of motor decline in CLN3 disease.

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Forbes, Jessica, and Ianessa Humbert. "Impact of the Chin-Down Posture on Temporal Measures of Patients With Dysphagia: A Pilot Study." American Journal of Speech-Language Pathology 30, no. 3 (May 18, 2021): 1049–60. http://dx.doi.org/10.1044/2021_ajslp-19-00223.

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Purpose The chin-down position is a commonly prescribed posture by health care professionals to alleviate the symptoms of dysphagia. Yet, how the technique influences swallowing physiology lacks clarity. Our goal was to examine the impact of the postural technique on patients with various medical conditions and swallowing impairments. Method Temporal and functional measures were examined with videofluoroscopy in the chin-down and neutral head position on 15 patients. Also, timing differences between head positions were examined to determine the presence of improvement during the chin-down posture. Results The primary finding was chin-down posture swallows prolonged the elapsed time between when the prematurely spilled bolus entered the pharynx relative to swallow onset compared to the neutral head position ( p = .006). Also, no improvement in airway protection was found when performing the postural technique. Conclusions The chin-down posture may benefit patients with specific swallowing impairments. However, the general use of the technique for all patients who experience swallowing difficulty might be negligent and could potentially have adverse or no effect on patient outcomes. Future studies examining patients with the same pathophysiology are needed to understand the benefit of the chin-down posture based on swallowing impairment.

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Cantrell, Brett W. "Generic Bank: Accounting for Debt Securities Sales and Impairments." Issues in Accounting Education 34, no. 4 (June 1, 2019): 15–29. http://dx.doi.org/10.2308/iace-52469.

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ABSTRACT This case examines the accounting rules for debt security impairments with a particular focus on the role of securities sales in determining whether debt securities are impaired. Generic Bank's securities portfolio contains material unrealized losses, and the bank desires to sell debt securities near the close of the fiscal year to free up resources for liquidity purposes. The case permits an examination of possible financial reporting consequences from security sales transactions under ASC 326-30, and how the structure, timing, and necessity of sales interacts with financial reporting discretion. The case also allows students to take the role of either a bank executive or an external auditor to understand how different incentives may influence areas of judgment within financial reporting. The case requirements are appropriate for upper-level undergraduate or graduate financial accounting courses.

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Sadighi, Zsila S., Elizabeth Curtis, Jennifer Zabrowksi, Catherine Billups, Amar Gajjar, Raja Khan, and Ibrahim Qaddoumi. "Neurologic impairments from pediatric low-grade glioma by tumor location and timing of diagnosis." Pediatric Blood & Cancer 65, no. 8 (May 9, 2018): e27063. http://dx.doi.org/10.1002/pbc.27063.

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Cheng, Ruey-Kuang, Mikel Etchegaray, and Warren H. Meck. "Impairments in timing, temporal memory, and reversal learning linked to neurotoxic regimens of methamphetamine intoxication." Brain Research 1186 (December 2007): 255–66. http://dx.doi.org/10.1016/j.brainres.2007.10.002.

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Light, Gregory A. "Probing cortico-cortical interactions that underlie the multiple sensory, cognitive, and everyday functional deficits in schizophrenia." Behavioral and Brain Sciences 27, no. 6 (December 2004): 799. http://dx.doi.org/10.1017/s0140525x04340185.

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Schizophrenia patients exhibit impairments across multiple clinical, cognitive, and functional domains. A fundamental abnormality of the timing and/or efficiency of neural processes across disparate brain regions (i.e., cortico-cortical communications) may underlie many of the deficits in schizophrenia. Because gamma synchrony is temporally correlated with many cognitive processes, probing patterns of gamma activation may shed light on the functional integrity of neural circuits in schizophrenia and related disorders.

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Nist, Marliese Dion, and Rita H. Pickler. "An Integrative Review of Cytokine/Chemokine Predictors of Neurodevelopment in Preterm Infants." Biological Research For Nursing 21, no. 4 (May 29, 2019): 366–76. http://dx.doi.org/10.1177/1099800419852766.

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Preterm infants are at risk of brain injury and poor neurodevelopmental outcomes including impairments in cognition, behavioral functioning, sensory perception, and motor performance. Systemic inflammation has been identified as an important, potentially modifiable precursor of neurologic and neurodevelopmental impairments. Inflammation is typically measured by quantifying circulating cytokines and chemokines. However, it is unclear which specific cytokines/chemokines most consistently predict neurodevelopment in preterm infants. In this integrative review, we evaluated and analyzed the literature ( N = 37 publications) to determine the cytokines/chemokines most predictive of neurodevelopment in preterm infants, the optimal timing for these measurements, and the ideal source for collecting cytokines/chemokines. Synthesis of the findings of these studies revealed that interleukin (IL)-6, IL-1β, IL-8, and tumor necrosis factor (TNF)-α collected during the first 3 weeks of life are most predictive of subsequent neurodevelopment. Methodological variation among studies hinders more specific analysis, including the evaluation of cytokine thresholds and meta-analyses, that would allow for the use of cytokines/chemokines to predict neurodevelopment. Future research should focus on identifying explicit cytokine values, specifically for IL-6, IL-1β, IL-8, and TNF-α, that are most predictive for identifying preterm infants most at risk of impairment, keeping in mind that longitudinal measures of cytokines/chemokines may be more predictive of future outcomes than single-time point measures.

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Piai, Vitória, Elke De Witte, Joanna Sierpowska, Xiaochen Zheng, Leighton B. Hinkley, Danielle Mizuiri, Robert T. Knight, Mitchel S. Berger, and Srikantan S. Nagarajan. "Language Neuroplasticity in Brain Tumor Patients Revealed by Magnetoencephalography." Journal of Cognitive Neuroscience 32, no. 8 (August 2020): 1497–507. http://dx.doi.org/10.1162/jocn_a_01561.

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Little is known about language impairment in brain tumor patients, especially in the presurgical phase. Impairment in this population may be missed because standardized tests fail to capture mild deficits. Additionally, neuroplasticity may also contribute to minimizing language impairments. We examined 14 presurgical patients with brain tumors in the language-dominant hemisphere using magnetoencephalography (MEG) while they performed a demanding picture–word interference task, that is, participants name pictures while ignoring distractor words. Brain tumor patients had behavioral picture-naming effects typically observed in healthy controls. The MEG responses also showed the expected pattern in its timing and amplitude modulation typical of controls, but with an altered spatial distribution of right hemisphere sources, in contrast to the classic left hemisphere source found in healthy individuals. This finding supports tumor-induced neural reorganization of language before surgery. Crucially, the use of electrophysiology allowed us to show the “same” neuronal response in terms of its timing and amplitude modulation in the right hemisphere, supporting the hypothesis that the processes performed by the right hemisphere following reorganization are similar in nature to those (previously) performed by the left hemisphere. We also identified one participant with a fast-growing tumor affecting large parts of critical language areas and underlying ventral and dorsal white matter tracts who showed a deviant pattern in behavior and in the MEG event-related responses. In conclusion, our results attest to the validity of using a demanding picture-naming task in presurgical patients and provide evidence for neuroplasticity, with the right hemisphere performing similar computations as the left hemisphere typically performs.

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Fernández-Ruiz, Antonio, Azahara Oliva, Marisol Soula, Florbela Rocha-Almeida, Gergo A. Nagy, Gonzalo Martin-Vazquez, and György Buzsáki. "Gamma rhythm communication between entorhinal cortex and dentate gyrus neuronal assemblies." Science 372, no. 6537 (April 1, 2021): eabf3119. http://dx.doi.org/10.1126/science.abf3119.

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Gamma oscillations are thought to coordinate the spike timing of functionally specialized neuronal ensembles across brain regions. To test this hypothesis, we optogenetically perturbed gamma spike timing in the rat medial (MEC) and lateral (LEC) entorhinal cortices and found impairments in spatial and object learning tasks, respectively. MEC and LEC were synchronized with the hippocampal dentate gyrus through high- and low-gamma-frequency rhythms, respectively, and engaged either granule cells or mossy cells and CA3 pyramidal cells in a task-dependent manner. Gamma perturbation disrupted the learning-induced assembly organization of target neurons. Our findings imply that pathway-specific gamma oscillations route task-relevant information between distinct neuronal subpopulations in the entorhinal-hippocampal circuit. We hypothesize that interregional gamma-time-scale spike coordination is a mechanism of neuronal communication.

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Loewke, Adrienne C., Alex Garrett, Athreya Steiger, Nathan Fisher, H. Craig Heller, Damien Colas, and Norman F. Ruby. "Loss of Circadian Timing Disrupts Theta Episodes during Object Exploration." Clocks & Sleep 2, no. 4 (December 1, 2020): 523–35. http://dx.doi.org/10.3390/clockssleep2040038.

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This study examined whether theta oscillations were compromised by the type of circadian disruption that impairs hippocampal-dependent memory processes. In prior studies on Siberian hamsters, we developed a one-time light treatment that eliminated circadian timing in the central pacemaker, the suprachiasmatic nucleus (SCN). These arrhythmic animals had impaired hippocampal-dependent memory whereas animals made arrhythmic with SCN lesions did not. The current study examined whether theta oscillations are compromised by the same light treatment that produced memory impairments in these animals. We found that both methods of inducing circadian-arrhythmia shortened theta episodes in the EEG by nearly 50%. SCN-lesioned animals, however, exhibited a 3-fold increase in the number of theta episodes and more than doubled the total time that theta dominated the EEG compared to SCN-intact circadian-arrhythmic animals. Video tracking showed that changes in theta were paralleled by similar changes in exploration behavior. These results suggest that the circadian-arrhythmic SCN interferes with hippocampal memory encoding by fragmenting theta oscillations. SCN-lesioned animals can, however, compensate for the shortened theta episodes by increasing their frequency. Implications for rhythm coherence and theta sequence models of memory formation are discussed.

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Illingworth, Gaby. "The challenges of adolescent sleep." Interface Focus 10, no. 3 (April 17, 2020): 20190080. http://dx.doi.org/10.1098/rsfs.2019.0080.

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Sleep is vital for our physical, emotional and cognitive health. However, adolescents face many challenges where their sleep is concerned. This is reflected in their sleep patterns including the timing of their sleep and how much sleep they achieve on a regular basis: their sleep is characteristically delayed and short. Notably, insufficient sleep is associated with impairments in adolescent functioning. Endogenous and exogenous factors are known to affect sleep at this age. Alterations in the bioregulation of sleep, comprising the circadian timing system and the sleep/wake homeostatic system, represent the intrinsic mechanisms at work. Compounding this, environmental, psychosocial and lifestyle factors may contribute to shortened sleep. This review discusses the amount of sleep gained by adolescents and its implications, the challenges to adolescent sleep and the interventions introduced in an effort to prioritize sleep health in this important developmental period.

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Walther, Sebastian, Fabian Ramseyer, Wolfgang Tschacher, Tim Vanbellingen, and Stephan Bohlhalter. "Poster #M190 DISORGANIZATION AND TIMING OF MOTOR BEHAVIOR: INSIGHT FROM GESTURE IMPAIRMENTS AND MOVEMENT PATTERNS IN SCHIZOPHRENIA." Schizophrenia Research 153 (April 2014): S259. http://dx.doi.org/10.1016/s0920-9964(14)70740-6.

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Sparkman, N. L., R. A. Kohman, and G. W. Boehm. "#129 Learning impairments induced by peripheral lipopolysaccharide administration are dependent upon frequency, dose, and timing of administration." Brain, Behavior, and Immunity 19, no. 4 (July 2005): e67. http://dx.doi.org/10.1016/j.bbi.2005.10.136.

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Rubia, K., E. Taylor, A. B. Smith, H. Oksannen, S. Overmeyer, and S. Newman. "Neuropsychological analyses of impulsiveness in childhood hyperactivity." British Journal of Psychiatry 179, no. 2 (August 2001): 138–43. http://dx.doi.org/10.1192/bjp.179.2.138.

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BackgroundNeuropsychological analyses of impulsiveness are needed to refine assessment of attention-deficit hyperactivity disorder (ADHD).AimsTo investigate specific impairments in hyperactive children in a neuropsychological task battery of impulsiveness, the Maudsley Attention and Response Suppression (MARS) task battery, and to identify the neural substrates.MethodImpulsiveness was assessed using different tasks of inhibitory control and time management (MARS) in 55 children with ADHD, other diagnoses and controls. Functional magnetic resonance images were obtained from adolescents with and without ADHD during three of the tasks.ResultsChildren with ADHD, but not psychiatric controls, were impaired on tests of response inhibition, but not of motor timing. Reduced right prefrontal activation was observed in hyperactive adolescents during higher level inhibition and delay management, but not during simple sensorimotor coordination.ConclusionsAttention-deficit hyperactivity disorder is characterised by specific deficits in tasks of motor response inhibition, but not motor timing, and by dysfunction of frontostriatal brain regions.

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Toplak, M. E., and R. Tannock. "Tapping and Anticipation Performance in Attention Deficit Hyperactivity Disorder." Perceptual and Motor Skills 100, no. 3 (June 2005): 659–75. http://dx.doi.org/10.2466/pms.100.3.659-675.

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The objective of this study was to examine the precise timing of a motor response in a sample of adolescents with ADHD and comparison participants. 46 participants with ADHD ( M age = 15.6, SD = 1.4; 40 boys) and 44 control participants ( M age = 15.3, SD = 1.4; 40 boys) were recruited through a metropolitan hospital. Participants were administered a tapping task and an anticipation task. Adolescents with ADHD displayed significantly more intra-individual variability on the visual 1000-msec. frequency interval of the tapping task and displayed lower accuracy on the cued and uncued trials of the anticipation task than comparison participants. Intra-individual variability on the tapping task was correlated with intra-individual variability on the anticipation task within both the ADHD and control groups. These findings suggest that adolescents with ADHD have impairments in both the cognitive representation and motor production of the precise timing of a motor response.

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Brinkerhoff, Sarah A., Patrick G. Monaghan, and Jaimie A. Roper. "Adapting gait with asymmetric visual feedback affects deadaptation but not adaptation in healthy young adults." PLOS ONE 16, no. 2 (February 25, 2021): e0247706. http://dx.doi.org/10.1371/journal.pone.0247706.

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Split-belt treadmill walking allows researchers to understand how new gait patterns are acquired. Initially, the belts move at two different speeds, inducing asymmetric step lengths. As people adapt their gait on a split-belt treadmill, left and right step lengths become more symmetric over time. Upon returning to normal walking, step lengths become asymmetric in the opposite direction, indicating deadaptation. Then, upon re-exposure to the split belts, step length asymmetry is less than the asymmetry at the start of the initial exposure, indicating readaptation. Changes in step length symmetry are driven by changes in step timing and step position asymmetry. It is critical to understand what factors can promote step timing and position adaptation and therefore influence step length asymmetry. There is limited research regarding the role of visual feedback to improve gait adaptation. Using visual feedback to promote the adaptation of step timing or position may be useful of understanding temporal or spatial gait impairments. We measured gait adaptation, deadaptation, and readaptation in twenty-nine healthy young adults while they walked on a split-belt treadmill. One group received no feedback while adapting; one group received asymmetric real-time feedback about step timing while adapting; and the last group received asymmetric real-time feedback about step position while adapting. We measured step length difference (non-normalized asymmetry), step timing asymmetry, and step position asymmetry during adaptation, deadaptation, and readaptation on a split-belt treadmill. Regardless of feedback, participants adapted step length difference, indicating that walking with temporal or spatial visual feedback does not interfere with gait adaptation. Compared to the group that received no feedback, the group that received temporal feedback exhibited smaller early deadaptation step position asymmetry (p = 0.005). There was no effect of temporal or spatial feedback on step timing. The feedback groups adapted step timing and position similarly to walking without feedback. Future work should investigate whether asymmetric visual feedback also results in typical gait adaptation in populations with altered step timing or position control.

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Demeter, Stephen L., Christopher Brigham, James B. Talmage, J. Mark Melhorn, and Steven D. Feinberg. "Apportionment of Musculoskeletal Injuries." Guides Newsletter 20, no. 5 (September 1, 2015): 3–11. http://dx.doi.org/10.1001/amaguidesnewsletters.2015.sepoct01.

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Abstract When they apportion impairment in musculoskeletal cases, evaluators encounter a variety of unique issues and problems. The first step in apportionment is scientifically based causation analysis. Arbitrary or opinion-based unscientific apportionment estimates that amount to little more than speculation should be avoided. The AMA Guides to the Evaluation of Permanent Impairment (AMA Guides), Fourth and Fifth Editions, are similar in their assessment of orthopedic impairment, but significant differences exist between these and the Sixth Edition. Individuals may experience impairments on several occasions. For example, if the first injury was rated using an earlier edition of the AMA Guides and a second injury occurs and is rated using a more current edition, then the most recent edition in the current jurisdiction is used to recalculate the rating for the first injury. Regarding which edition of the AMA Guides to use, evaluators should be aware of the jurisdictional requirements and also the timing to ensure that the individual is at maximum medical improvement. If the issue to be determined is apportioning the cause of the injury and not the impairment rating, then different criteria are used and the AMA Guides to the Evaluation of Disease and Injury Causation, Second Edition, is an invaluable resource. Extensive sidebars discuss qualitative vs qualitative apportionment and steps that evaluators can take to ensure that body regions and conditions are not confused (ie, that an apples-to-apples comparison is taking place).

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Pedro, Victor M., Nicole C. Lim, and Elena Oggero. "CORTICAL INTEGRATIVE THERAPY EFFECTIVENESS IN THE TREATMENT OF POST-CONCUSSION SYNDROME AND MILD TRAUMATIC BRAIN INJURY." Biomedical Sciences Instrumentation 57, no. 2 (April 1, 2021): 191–98. http://dx.doi.org/10.34107/yhpn942204191.

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Post-Concussion Syndrome (PCS) is a relatively prevalent condition that emerges after sustaining a head injury. Individuals with PCS experience prolonged impairments and distress associated with the injury which can impact the individuals’ quality of life experiences. In this retrospective chart review of refractory adult patients diagnosed with PCS and mild Traumatic Brain Injury (mTBI), the effectiveness of Cortical Integrative Therapy (PedroCIT®) was investigated by comparing measures of postural stability, brain sequencing and timing, and self-reports of physical and psychosocial symptoms of PCS obtained before and after PedroCIT®. Multivariate and Repeated Measures General Linear Models showed improvements across the measures from before to after treatment in all subjects, highlighting the effectiveness of PedroCIT®. To further underscore the capacity of PedroCIT® to elicit improvements in patients who have been resistant to treatment prior to PedroCIT®, the duration of time that the subjects underwent PedroCIT® was compared to the duration of time since the injury to the subjects’ first PedroCIT® intervention session. The findings of this study showed significant improvements from pre- to post-treatment in postural stability, brain sequencing and timing, and self-reported symptoms for patients affected by PCS and mTBI, and treatment outcomes were largely not contingent upon the severity of the condition at the beginning of treatment. Altogether, this retrospective study suggests that refractory individuals affected by PCS and mTBI can benefit from undergoing PedroCIT® and their treatment outcomes may not be related to the degree of impairment presented at the beginning of treatment.

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Mehta, Rupal, Marco Cannella, Sharon M. Henry, Susan Smith, Simon Giszter, and Sheri P. Silfies. "Trunk Postural Muscle Timing Is Not Compromised In Low Back Pain Patients Clinically Diagnosed With Movement Coordination Impairments." Motor Control 21, no. 2 (April 2017): 133–57. http://dx.doi.org/10.1123/mc.2015-0049.

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Smith DaWalt, Leann, Jinkuk Hong, Jan S. Greenberg, and Marsha R. Mailick. "Mortality in individuals with autism spectrum disorder: Predictors over a 20-year period." Autism 23, no. 7 (February 28, 2019): 1732–39. http://dx.doi.org/10.1177/1362361319827412.

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Research has shown that individuals with autism spectrum disorder have higher rates of health problems throughout childhood, adolescence, and adulthood, and that this may result in elevated risk of early mortality. This study reported the rate, timing, and causes of death in a large community-based cohort of adolescents and adults with autism spectrum disorder ( n = 406) over a 20-year period (1998–2018) and identified predictors of mortality. Over this period, 6.4% of individuals died at an average age of 39 years. Causes of death included chronic conditions (such as cancer and heart disease), accidents (such as choking on food and accidental poisoning), and health complications due to medication side effects. Even after controlling for age and health status, significant predictors of mortality were early childhood levels of impairments in social reciprocity and high levels of functional impairments at the start of the study period. The results suggest the importance of social engagement and functional self-sufficiency across the life course, as well as adequate access to health care for individuals with autism spectrum disorder.

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Iqbal, Naveed, Abdulmajid Lawal, and Azzedine Zerguine. "MitigatingWireless Channel Impairments in Seismic Data Transmission Using Deep Neural Networks." Sensors 21, no. 18 (September 12, 2021): 6105. http://dx.doi.org/10.3390/s21186105.

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The traditional cable-based geophone network is an inefficient way of seismic data transmission owing to the related cost and weight. The future of oil and gas exploration technology demands large-scale seismic acquisition, versatility, flexibility, scalability, and automation. On the one hand, a typical seismic survey can pile up a massive amount of raw seismic data per day. On the other hand, the need for wireless seismic data transmission remains immense. Moving from pre-wired to wireless geophones faces major challenges given the enormous amount of data that needs to be transmitted from geophones to the on-site data collection center. The most important factor that has been ignored in the previous studies for the realization of wireless seismic data transmission is wireless channel effects. While transmitting the seismic data wirelessly, impairments like interference, multi-path fading, and channel noise need to be considered. Therefore, in this work, a novel amalgamation of blind channel identification and deep neural networks is proposed. As a geophone already is responsible for transmitting a tremendous amount of data under tight timing constraints, the proposed setup eschews sending any additional training signals for the purpose of mitigating the channel effects. Note that the deep neural network is trained only on synthetic seismic data without the need to use real data in the training process. Experiments show that the proposed method gives promising results when applied to the real/field data set.

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Seamon, Bryant A., Richard R. Neptune, and Steven A. Kautz. "Using a Module-Based Analysis Framework for Investigating Muscle Coordination during Walking in Individuals Poststroke: A Literature Review and Synthesis." Applied Bionics and Biomechanics 2018 (June 3, 2018): 1–16. http://dx.doi.org/10.1155/2018/3795754.

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Factorization methods quantitatively group electromyographic signals from several muscles during dynamic tasks into multiple modules where each module consists of muscles that are coactive during the movement. Module-based analyses may provide an analytical framework for testing theories of poststroke motor control recovery based on one’s ability to move independently from mass flexion-extension muscle group coactivation. Such a framework may be useful for understanding the causality between underlying neural impairments, biomechanical function, and walking performance in individuals poststroke. Our aim is to synthesize current evidence regarding the relationships between modules, gait mechanics, and rehabilitation in individuals poststroke. We synthesized eleven studies that performed module-based analyses during walking tasks for individuals poststroke. Modules were primarily identified by nonnegative matrix factorization, and fewer modules correlated with poor walking performance on biomechanical and clinical measures. Fewer modules indicated reduced ability to control individual muscle timing during paretic leg stance. There was evidence that rehabilitation can lead to the use of more and/or better-timed modules. While future work will need to establish the ability of modules to identify impairment mechanisms, they appear to offer a promising analytical approach for evaluating motor control.

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McBean, Amanda L., and Hawley E. Montgomery-Downs. "Diurnal Fatigue Patterns, Sleep Timing, and Mental Health Outcomes Among Healthy Postpartum Women." Biological Research For Nursing 17, no. 1 (March 24, 2014): 29–39. http://dx.doi.org/10.1177/1099800414528278.

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Postpartum women have frequently interrupted sleep, report high levels of fatigue, and may experience circadian rhythm disruptions. They are also susceptible to mood impairments, anxiety, and stress. The current study explored associations between maternal postpartum daily fatigue patterns, which should vary according to circadian influences and mental health. Seventy-one primiparous, healthy mothers completed multiple daily self-reports of fatigue during postpartum Weeks 2 and 12 and were categorized at each week as having either a rhythmic or random fatigue pattern during the daytime. Wrist actigraphy data were used to calculate sleep midpoints. Surveys assessed chronotype, mood, anxiety, and stress. At postpartum Week 2, there were no differences in mental health measures between fatigue groups. At postpartum Week 12, higher overall fatigue levels were associated with increased anxiety, stress, and mood disruption. However, overall fatigue levels did not differ between fatigue groups. Women with a rhythmic fatigue pattern reported significantly less stress and more vigor than women with a random fatigue pattern. An earlier sleep midpoint was associated with a rhythmic fatigue pattern during postpartum Week 12. These data suggest that, despite similar average daily fatigue levels, having a rhythmic daily pattern of fatigue may be advantageous for mental health outcomes among postpartum women.

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Li, Xue, Lu Wang, Shuling Zhang, Xiang Hu, Huijun Yang, and Lei Xi. "Timing-Dependent Protection of Swimming Exercise against d-Galactose-Induced Aging-Like Impairments in Spatial Learning/Memory in Rats." Brain Sciences 9, no. 9 (September 14, 2019): 236. http://dx.doi.org/10.3390/brainsci9090236.

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This study was designed to investigate beneficial effects of swimming exercise training on learning/memory, synaptic plasticity and CREB (cAMP response element binding protein) expression in hippocampus in a rat model of d-galactose-induced aging (DGA). Eighty adult male rats were randomly divided into four groups: Saline Control (group C), DGA (group A), Swimming exercise before DGA (group S1), and Swimming during DGA (group S2). These four groups of animals were further divided into Morris water maze training group (M subgroup) and sedentary control group (N subgroup). Spatial learning/memory was tested using Morris water maze training. The number and density of synaptophysin (Syp) and metabotropic glutamate receptor 1 (mGluR1) in hippocampal dentate gyrus area, CREB mRNA and protein expression and DNA methylation levels were determined respectively with immunohistochemistry, western blot, real-time PCR, and MassArray methylation detection platform. We found that compared with group C, DGA rats showed aging-like poor health and weight loss as well as hippocampal neurodegenerative characteristics. Exercise training led to a time-dependent decrease in average escape latency and improved spatial memory. Exercise training group (S2M) had significantly increased swim distance as compared with controls. These functional improvements in S2M group were associated with higher Syp and mGluR1 values in hippocampus (p < 0.01) as well as higher levels of hippocampal CREB protein/mRNA expression and gene methylation. In conclusion, swimming exercise training selectively during drug-induced aging process protected hippocampal neurons against DGA-elicited degenerative changes and in turn maintained neuronal synaptic plasticity and learning/memory function, possibly through upregulation of hippocampal CREB protein/mRNA and reduction of DGA-induced methylation of CREB.

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Desrochers, Brunfeldt, Sidiropoulos, and Kagerer. "Sensorimotor Control in Dystonia." Brain Sciences 9, no. 4 (April 11, 2019): 79. http://dx.doi.org/10.3390/brainsci9040079.

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This is an overview of the sensorimotor impairments in dystonia, a syndrome characterized by sustained or intermittent aberrant movement patterns leading to abnormal movements and/or postures with or without a tremulous component. Dystonia can affect the entire body or specific body regions and results from a plethora of etiologies, including subtle changes in gray and white matter in several brain regions. Research over the last 25 years addressing topics of sensorimotor control has shown functional sensorimotor impairments related to sensorimotor integration, timing, oculomotor and head control, as well as upper and lower limb control. In the context of efforts to update the classification of dystonia, sensorimotor research is highly relevant for a better understanding of the underlying pathology, and potential mechanisms contributing to global and regional dysfunction within the central nervous system. This overview of relevant research regarding sensorimotor control in humans with idiopathic dystonia attempts to frame the dysfunction with respect to what is known regarding motor control in patients and healthy individuals. We also highlight promising avenues for the future study of neuromotor control that may help to further elucidate dystonia etiology, pathology, and functional characteristics.

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Rebstock, Alicia M., and Sarah E. Wallace. "Effects of a Combined Semantic Feature Analysis and Multimodal Treatment for Primary Progressive Aphasia: Pilot Study." Communication Disorders Quarterly 41, no. 2 (September 10, 2018): 71–85. http://dx.doi.org/10.1177/1525740118794399.

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Primary progressive aphasia (PPA) is a neurodegenerative condition characterized by language and cognitive decline. Word-retrieval deficits are the most common PPA symptom and contribute to impaired spoken expression. Intense semantic interventions show promise for improving word retrieval in people with PPA. In addition, people with PPA may learn to use alternative communication modalities when they are unable to retrieve a word. However, executive function impairments can cause people to struggle to switch among modalities to repair communication breakdowns.This study examined the effects of a combined semantic feature analysis and multimodal communication program (SFA+MCP) on word-retrieval accuracy, switching among modalities, and overall communicative effectiveness in a person with PPA. An adult female with PPA completed SFA+MCP. Baseline, probe, intervention, and postintervention sessions were completed to measure word-retrieval accuracy and switching between communication modalities. A postintervention listener task was completed to measure communicative effectiveness. Changes in word-retrieval accuracy and switching were minimal. However, the listeners’ identification of the participant’s communication attempts was more accurate following treatment, suggesting increased overall communicative effectiveness. Further investigations of SFA+MCP, specifically relative to timing, intensity, and appropriate modifications for people with cognitive impairments associated with PPA are warranted.

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Schimmel, Wietske C. M., Karin Gehring, Patrick E. J. Hanssens, and Margriet M. Sitskoorn. "Cognitive functioning and predictors thereof in patients with 1–10 brain metastases selected for stereotactic radiosurgery." Journal of Neuro-Oncology 145, no. 2 (September 24, 2019): 265–76. http://dx.doi.org/10.1007/s11060-019-03292-y.

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Abstract Purpose Information on predictive factors of cognitive functioning in patients with (multiple) brain metastases (BM) selected for radiosurgery may allow for more individual care and may play a role in predicting cognitive outcome after radiosurgery. The aim of this study was to evaluate cognitive performance, and predictors thereof, in patients with 1–10 BM before radiosurgery. Methods Cognition was measured before radiosurgery using a standardized neuropsychological test battery in patients with 1–10 BM (expected survival > 3 months; KPS ≥ 70; no prior BM treatment). Regression formulae were constructed to calculate sociodemographically corrected z scores. Group and individual cognitive functioning was analyzed. Multivariable regression was used to explore potential predictors. Results Patients (N = 92) performed significantly worse than controls (N = 104) on all 11 test variables (medium-large effect sizes for 8 variables). Percentages of impairment were highest for information processing (55.3%), dexterity (43.2%) and cognitive flexibility (28.7%). 62% and 46% of patients had impairments in at least two, or three test variables, respectively. Models including combinations of clinical and psychological variables were predictive of verbal memory, psychomotor speed, information processing and dexterity. Neither number nor volume of metastases predicted patients’ test performance. Conclusions Already before radiosurgery, almost half of the patients suffered from severe cognitive deficits in at least three test variables. At group and individual level, information processing, cognitive flexibility, and dexterity were most affected. These cognitive impairments may impair daily functioning and patients’ ability to make (shared) treatment decisions. Both clinical (symptomatic BM; timing of BM diagnosis) and psychological (mental fatigue) characteristics influenced cognitive performance. Clinical trial information Cognition and Radiation Study A (CAR-Study A; ClinicalTrials.gov Identifier: NCT02953756; Medical Ethics Committee file number: NL53472.028.15/P1515).

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Sveistrup, Heidi, Patricia A. Burtner, and Marjorie H. Woollacott. "Two Motor Control Approaches That May Help to Identify and Teach Children with Motor Impairments." Pediatric Exercise Science 4, no. 3 (August 1992): 249–69. http://dx.doi.org/10.1123/pes.4.3.249.

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Children in physical education classes, special education classes, and rehabilitation programs have extremely varied abilities and deficits in motor tasks. Among the problems faced by the teachers, therapists, and other specialists is the identification of the underlying mechanisms that produce the problems observed in these children. In addition, teachers and others must design an appropriate intervention strategy. This paper discusses two approaches being used to study the underlying systems and computations that contribute to the control and regulation of movement. The systems approach focuses on the problems that children with specific pathologies have in regulating their balance and equilibrium. The computational or modular approach addresses the motor deficits observed in certain children in terms of three possible computational units: timing, force production, and motor sequencing. These approaches may provide additional techniques for identifying the pathology underlying the behavioral deficits of children with motor impairment. Also, with these tools it may be possible to design alternative programs that will address the causes as well as the effects of the deficits observed in certain groups of children.

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Bonuzzi, Giordano Marcio Gatinho, Umberto César Corrêa, Gisele Ladik Antunes, Carlos Bandeira de Mello Monteiro, Alaércio Perotti Júnior, Andrea Michele Freudenheim, and Camila Torriani-Pasin. "Effects of the task complexity on the performance of a Coincidence Timing Task of people with Down syndrome." Motricidade 12, no. 4 (May 3, 2017): 15. http://dx.doi.org/10.6063/motricidade.7318.

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With the present study, we aimed to investigate the task complexity effects on the performance of a coincidence timing task in individuals with Down syndrome. The experimental group was consisted by 26 subjects with Down syndrome, 20 years old (± 5), and classified as mild or moderate in International Classification of Functioning and Health. Each participant in the experimental group was matched by in function of gender and age with a participant in a control group without Down syndrome. Both groups performed a coincident timing task, in which the participant had different levels of structural and functional complexity. Performance measure was derived from the consistency (absolute error), accuracy (variable error) and direction of response (constant error). Individuals with Down syndrome presented spatiotemporal organization impairments related to the difficulty in dealing with motor demand in order to interact with the perceptive demand. They also experienced difficulty in adapt to task complexity, causing performance error in the task. Individuals with Down syndrome have deficits in perceptive and space-time organization, and this phenomenon may be explained by the difficulty in integrating perceptive stimulus to motor actions with a high number of elements involved.

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Prendergast, Andrew J. "Malnutrition and vaccination in developing countries." Philosophical Transactions of the Royal Society B: Biological Sciences 370, no. 1671 (June 19, 2015): 20140141. http://dx.doi.org/10.1098/rstb.2014.0141.

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Malnutrition contributes to an estimated 45% of deaths among children under 5 years of age in developing countries, predominantly due to infections. Malnourished children therefore stand to benefit hugely from vaccination, but malnutrition has been described as the most common immunodeficiency globally, suggesting that they may not be able to respond effectively to vaccines. The immunology of malnutrition remains poorly characterized, but is associated with impairments in mucosal barrier integrity, and innate and adaptive immune dysfunction. Despite this, the majority of malnourished children can mount a protective immune response following vaccination, although the timing, quality and duration of responses may be impaired. This paper reviews the evidence for vaccine immunogenicity in malnourished children, discusses the importance of vaccination in prevention of malnutrition and highlights evidence gaps in our current knowledge.

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Sonuga-Barke, Edmund, Paraskevi Bitsakou, and Margaret Thompson. "Beyond the Dual Pathway Model: Evidence for the Dissociation of Timing, Inhibitory, and Delay-Related Impairments in Attention-Deficit/Hyperactivity Disorder." Journal of the American Academy of Child & Adolescent Psychiatry 49, no. 4 (April 2010): 345–55. http://dx.doi.org/10.1016/j.jaac.2009.12.018.

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Cahana-Amitay, Dalia, Avron Spiro, Jason A. Cohen, Abigail C. Oveis, Emmanuel A. Ojo, Jesse T. Sayers, Loraine K. Obler, and Martin L. Albert. "Effects of Metabolic Syndrome on Language Functions in Aging." Journal of the International Neuropsychological Society 21, no. 2 (February 2015): 116–25. http://dx.doi.org/10.1017/s1355617715000028.

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AbstractThis study explored effects of the metabolic syndrome (MetS) on language in aging. MetS is a constellation of five vascular and metabolic risk factors associated with the development of chronic diseases and increased risk of mortality, as well as brain and cognitive impairments. We tested 281 English-speaking older adults aged 55–84, free of stroke and dementia. Presence of MetS was based on the harmonized criteria (Alberti et al., 2009). Language performance was assessed by measures of accuracy and reaction time on two tasks of lexical retrieval and two tasks of sentence processing. Regression analyses, adjusted for age, education, gender, diabetes, hypertension, and heart disease, demonstrated that participants with MetS had significantly lower accuracy on measures of lexical retrieval (action naming) and sentence processing (embedded sentences, both subject and object relative clauses). Reaction time was slightly faster on the test of embedded sentences among those with MetS. MetS adversely affects the language performance of older adults, impairing accuracy of both lexical retrieval and sentence processing. This finding reinforces and extends results of earlier research documenting the negative influence of potentially treatable medical conditions (diabetes, hypertension) on language performance in aging. The unanticipated finding that persons with MetS were faster in processing embedded sentences may represent an impairment of timing functions among older individuals with MetS. (JINS, 2015, 21, 116–125)

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LeBlanc, Jocelyn J., and Michela Fagiolini. "Autism: A “Critical Period” Disorder?" Neural Plasticity 2011 (2011): 1–17. http://dx.doi.org/10.1155/2011/921680.

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Cortical circuits in the brain are refined by experience during critical periods early in postnatal life. Critical periods are regulated by the balance of excitatory and inhibitory (E/I) neurotransmission in the brain during development. There is now increasing evidence of E/I imbalance in autism, a complex genetic neurodevelopmental disorder diagnosed by abnormal socialization, impaired communication, and repetitive behaviors or restricted interests. The underlying cause is still largely unknown and there is no fully effective treatment or cure. We propose that alteration of the expression and/or timing of critical period circuit refinement in primary sensory brain areas may significantly contribute to autistic phenotypes, including cognitive and behavioral impairments. Dissection of the cellular and molecular mechanisms governing well-established critical periods represents a powerful tool to identify new potential therapeutic targets to restore normal plasticity and function in affected neuronal circuits.

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Novaira, Horacio J., Ariel L. Negron, Jones B. Graceli, Silvia Capellino, Andrew Schoeffield, Gloria E. Hoffman, Jon E. Levine, Andrew Wolfe, Fredric E. Wondisford, and Sally Radovick. "Impairments in the reproductive axis of female mice lacking estrogen receptor β in GnRH neurons." American Journal of Physiology-Endocrinology and Metabolism 315, no. 5 (November 1, 2018): E1019—E1033. http://dx.doi.org/10.1152/ajpendo.00173.2018.

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The effect of estrogen on the differentiation and maintenance of reproductive tissues is mediated by two nuclear estrogen receptors (ERs), ERα, and ERβ. Lack of functional ERα and ERβ genes in vivo significantly affects reproductive function; however, the target tissues and signaling pathways in the hypothalamus are not clearly defined. Here, we describe the generation and reproductive characterization of a complete-ERβ KO (CERβKO) and a GnRH neuron-specific ERβKO (GERβKO) mouse models. Both ERβKO mouse models displayed a delay in vaginal opening and first estrus. Hypothalamic gonadotropin-releasing hormone (GnRH) mRNA expression levels in both ERβKO mice were similar to control mice; however female CERβKO and GERβKO mice had lower basal and surge serum gonadotropin levels. Although a GnRH stimulation test in both female ERβKO models showed preserved gonadotropic function in the same animals, a kisspeptin stimulation test revealed an attenuated response by GnRH neurons, suggesting a role for ERβ in normal GnRH neuron function. No alteration in estrogen-negative feedback was observed in either ERβKO mouse models after ovariectomy and estrogen replacement. Further, abnormal development of ovarian follicles with low serum estradiol levels and impairment of fertility were observed in both ERβKO mouse models. In male ERβKO mice, no differences in the timing of pubertal onset or serum luteinizing hormone and follicle-stimulating hormone levels were observed as compared with controls. Taken together, these data provide in vivo evidence for a role of ERβ in GnRH neurons in modulating puberty and reproduction, specifically through kisspeptin responsiveness in the female hypothalamic-pituitary-gonadal axis.

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Ware, Janice, Jennifer L. Butcher, Beatrice Latal, Anjali Sadhwani, Caitlin K. Rollins, Cheryl L. Brosig Soto, Samantha C. Butler, Patricia B. Eiler-Sims, Catherine V. Ullman Shade, and Gil Wernovsky. "Neurodevelopmental evaluation strategies for children with congenital heart disease aged birth through 5 years: recommendations from the cardiac neurodevelopmental outcome collaborative." Cardiology in the Young 30, no. 11 (November 2020): 1609–22. http://dx.doi.org/10.1017/s1047951120003534.

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AbstractThis paper provides specific guidelines for the neurodevelopmental evaluation of children aged birth through 5 years with complex congenital heart disease. There is wide recognition that children with congenital heart disease are at high risk for neurodevelopmental impairments that are first apparent in infancy and often persist as children mature. Impairments among children with complex congenital heart disease cross developmental domains and affect multiple functional abilities. The guidelines provided are derived from the substantial body of research generated over the past 30 years describing the characteristic developmental profiles and the long-term trajectories of children surviving with complex congenital heart conditions. The content and the timing of the guidelines are consistent with the 2012 American Heart Association and the American Academy of Pediatrics scientific statement documenting the need for ongoing developmental monitoring and assessment from infancy through adolescence. The specific guidelines offered in this article were developed by a multidisciplinary clinical research team affiliated with the Cardiac Neurodevelopmental Outcome Collaborative, a not-for-profit organisation established to determine and implement best neurodevelopmental practices for children with congenital heart disease. The guidelines are designed for use in clinical and research applications and offer an abbreviated core protocol and an extended version that expands the scope of the evaluation. The guidelines emphasise the value of early risk identification, use of evidence-based assessment instruments, consideration of family and cultural preferences, and the importance of providing multidimensional community-based services to remediate risk.

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Kadic, Aida Salihagic. "Fetal Neurology: The Role of Fetal Stress." Donald School Journal of Ultrasound in Obstetrics and Gynecology 9, no. 1 (2015): 30–39. http://dx.doi.org/10.5005/jp-journals-10009-1386.

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ABSTRACT Fetal development and growth, as well as the timing of birth is influenced by the intrauterine environment. Many environmental factors causing the fetal stress can interfere with fetal development and leave long-term and profound consequences on health. Fetal glucocorticoid overexposure has primarily significant consequences for the development of the central nervous system. In response to an adverse intrauterine conditions, the fetus is able to adapt its physiology to promote survival. However, these adaptations can result in permanent changes in tissue and organ structure and function that directly ‘program’ predisposition to disease. Cardiometabolic disorders, behavioral alterations and neuropsychiatric impairments in adulthood and/ or childhood may have their roots in the fetal period of life. Fetal response to stress and its prenatal and lifelong consequences are discussed in this review. How to cite this article Kadić AS. Fetal Neurology: The Role of Fetal Stress. Donald School J Ultrasound Obstet Gynecol 2015;9(1):30-39.

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Schwerdt, H. N., K. Amemori, D. J. Gibson, L. L. Stanwicks, T. Yoshida, N. P. Bichot, S. Amemori, et al. "Dopamine and beta-band oscillations differentially link to striatal value and motor control." Science Advances 6, no. 39 (September 2020): eabb9226. http://dx.doi.org/10.1126/sciadv.abb9226.

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Parkinson’s disease is characterized by decreased dopamine and increased beta-band oscillatory activity accompanying debilitating motor and mood impairments. Coordinate dopamine-beta opposition is considered a normative rule for basal ganglia function. We report a breakdown of this rule. We developed multimodal systems allowing the first simultaneous, chronic recordings of dopamine release and beta-band activity in the striatum of nonhuman primates during behavioral performance. Dopamine and beta signals were anticorrelated over seconds-long time frames, in agreement with the posited rule, but at finer time scales, we identified conditions in which these signals were modulated with the same polarity. These measurements demonstrated that task-elicited beta suppressions preceded dopamine peaks and that relative dopamine-beta timing and polarity depended on reward value, performance history, movement, and striatal domain. These findings establish a new view of coordinate dopamine and beta signaling operations, critical to guide novel strategies for diagnosing and treating Parkinson’s disease and related neurodegenerative disorders.

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Speth, Robert C., Mikayla D’Ambra, Hong Ji, and Kathryn Sandberg. "A heartfelt message, estrogen replacement therapy: use it or lose it." American Journal of Physiology-Heart and Circulatory Physiology 315, no. 6 (December 1, 2018): H1765—H1778. http://dx.doi.org/10.1152/ajpheart.00041.2018.

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The issue of cardiovascular and cognitive health in women is complex. During the premenopausal phase of life, women have healthy blood pressure levels that are lower than those of age-matched men, and they have less cardiovascular disease. However, in the postmenopausal stage of life, blood pressure in women increases, and they are increasingly susceptible to cardiovascular disease, cognitive impairments, and dementia, exceeding the incidence in men. The major difference between pre- and postmenopausal women is the loss of estrogen. Thus, it seemed logical that postmenopausal estrogen replacement therapy, with or without progestin, generally referred to as menopausal hormone treatment (MHT), would prevent these adverse sequelae. However, despite initially promising results, a major randomized clinical trial refuted the benefits of MHT, leading to its falling from favor. However, reappraisal of this study in the framework of a “critical window,” or “timing hypothesis,” has changed our perspective on the benefit-to-risk ratio of MHT, and this review discusses the historical, current, and future approaches to MHT.

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Bonnan, Mickael, and Philippe Cabre. "Plasma Exchange in Severe Attacks of Neuromyelitis Optica." Multiple Sclerosis International 2012 (2012): 1–9. http://dx.doi.org/10.1155/2012/787630.

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Background. Neuromyelitis optica (NMO) attacks are poorly controlled by steroids and evolve in stepwise neurological impairments. Assuming the strong humoral response underlying NMO attacks, plasma exchange (PLEX) is an appropriate technique in severe NMO attacks.Objective. Presenting an up-to-date review of the literature of PLEX in NMO.Methods. We summarize the rationale of PLEX in relation with the physiology of NMO, the main technical aspects, and the available studies.Results. PLEX in severe attacks from myelitis or optic neuritis are associated with a better outcome, depending on PLEX delay (“time is cord and eyes”). NMO-IgG status has no influence. Finally, we build up an original concept linking the inner dynamic of the lesion, the timing of PLEX onset and the expected clinical results.Conclusion. PLEX is a safe and efficient add-on therapy in NMO, in synergy with steroids. Large therapeutic trials are required to definitely assess the procedure and define the time opportunity window.

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Tucker-Drob, Elliot M. "Cognitive Aging and Dementia: A Life-Span Perspective." Annual Review of Developmental Psychology 1, no. 1 (December 24, 2019): 177–96. http://dx.doi.org/10.1146/annurev-devpsych-121318-085204.

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This review summarizes empirical findings and theoretical concepts in cognitive aging and late-life dementia research, with emphases on ( a) person-to-person heterogeneity in trajectories of cognitive change over time, ( b) how trajectories of child cognitive development determine peak levels of adult cognitive function from which aging-related cognitive declines occur, and ( c) how lifelong trajectories of cognitive function relate to the timing of severe cognitive impairments characteristic of dementia. I consider conceptual issues surrounding categorical versus dimensional models of late-life dementia and discuss how current diagnostic approaches affect inferences in the empirical study of disease progression. Together, the incomplete current understanding of the biological foundations of aging-related cognitive declines and the continuous nature of many biomarkers commonly used in dementia diagnosis and classification pose both opportunities and challenges in the current research landscape. Future research will benefit from accurately measuring and analyzing continuous variation in longitudinal trajectories of cognitive function.

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Jacobson, Tara K., Matthew D. Howe, Brandy Schmidt, James R. Hinman, Monty A. Escabí, and Etan J. Markus. "Hippocampal theta, gamma, and theta-gamma coupling: effects of aging, environmental change, and cholinergic activation." Journal of Neurophysiology 109, no. 7 (April 1, 2013): 1852–65. http://dx.doi.org/10.1152/jn.00409.2012.

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Hippocampal theta and gamma oscillations coordinate the timing of multiple inputs to hippocampal neurons and have been linked to information processing and the dynamics of encoding and retrieval. One major influence on hippocampal rhythmicity is from cholinergic afferents. In both humans and rodents, aging is linked to impairments in hippocampus-dependent function along with degradation of cholinergic function. Cholinomimetics can reverse some age-related memory impairments and modulate oscillations in the hippocampus. Therefore, one would expect corresponding changes in these oscillations and possible rescue with the cholinomimetic physostigmine. Hippocampal activity was recorded while animals explored a familiar or a novel maze configuration. Reexposure to a familiar situation resulted in minimal aging effects or changes in theta or gamma oscillations. In contrast, exploration of a novel maze configuration increased theta power; this was greater in adult than old animals, although the deficit was reversed with physostigmine. In contrast to the theta results, the effects of novelty, age, and/or physostigmine on gamma were relatively weak. Unrelated to the behavioral situation were an age-related decrease in the degree of theta-gamma coupling and the fact that physostigmine lowered the frequency of theta in both adult and old animals. The results indicate that age-related changes in gamma and theta modulation of gamma, while reflecting aging changes in hippocampal circuitry, seem less related to aging changes in information processing. In contrast, the data support a role for theta and the cholinergic system in encoding and that hippocampal aging is related to impaired encoding of new information.

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Baek, K., N. Doñamayor, L. S. Morris, D. Strelchuk, S. Mitchell, Y. Mikheenko, S. Y. Yeoh, et al. "Impaired awareness of motor intention in functional neurological disorder: implications for voluntary and functional movement." Psychological Medicine 47, no. 9 (February 10, 2017): 1624–36. http://dx.doi.org/10.1017/s0033291717000071.

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Abstract:

BackgroundFunctional neurological disorders (FNDs), also known as conversion disorder, are unexplained neurological symptoms unrelated to a neurological cause. The disorder is common, yet poorly understood. The symptoms are experienced as involuntary but have similarities to voluntary processes. Here we studied intention awareness in FND.MethodA total of 26 FND patients and 25 healthy volunteers participated in this functional magnetic resonance study using Libet's clock.ResultsFND is characterized by delayed awareness of the intention to move relative to the movement itself. The reporting of intention was more precise, suggesting that these findings are reliable and unrelated to non-specific attentional deficits. That these findings were more prominent with aberrant positive functional movement symptoms rather than negative symptoms may be relevant to impairments in timing for an inhibitory veto process. Attention towards intention relative to movement was associated with lower right inferior parietal cortex activity in FND, a region early in the processing of intention. During rest, aberrant functional connectivity was observed with the right inferior parietal cortex and other motor intention regions.ConclusionsThe results converge with observations of low inferior parietal activity comparing involuntary with voluntary movement in FND, emphasizing core deficiencies in intention. Heightened precision of this impaired intention is consistent with Bayesian theories of impaired top-down priors that might influence the sense of involuntariness. A primary impairment in voluntary motor intention at an early processing stage might explain clinical observations of slowed effortful voluntary movement, heightened self-directed attention and underlie functional movements. These findings further suggest novel therapeutic targets.

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Journal articles on the topic 'Timing impairments'

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