Task-dependent modulation of the visual sensory thalamus assists visual-speech recognition

The cerebral cortex modulates early sensory processing via feed-back connections to sensory pathway nuclei. The functions of this top-down modulation for human behavior are poorly understood. Here, we show that top-down modulation of the visual sensory thalamus (the lateral geniculate body, LGN) is involved in visual-speech recognition. In two independent functional magnetic resonance imaging (fMRI) studies, LGN response increased when participants processed fast-varying features of articulatory movements required for visual-speech recognition, as compared to temporally more stable features required for face identification with the same stimulus material. The LGN response during the visual-speech task correlated positively with the visual-speech recognition scores across participants. In addition, the task-dependent modulation was present for speech movements and did not occur for control conditions involving non-speech biological movements. In face-to-face communication, visual speech recognition is used to enhance or even enable understanding what is said. Speech recognition is commonly explained in frameworks focusing on cerebral cortex areas. Our findings suggest that task-dependent modulation at subcortical sensory stages has an important role for communication: Together with similar findings in the auditory modality the findings imply that task-dependent modulation of the sensory thalami is a general mechanism to optimize speech recognition

Reduced structural connectivity between left auditory thalamus and the motion-sensitive planum temporale in developmental dyslexia

Developmental dyslexia is characterized by the inability to acquire typical reading and writing skills. Dyslexia has been frequently linked to cerebral cortex alterations; however recent evidence also points towards sensory thalamus dysfunctions: dyslexics showed reduced responses in the left auditory thalamus (medial geniculate body, MGB) during speech processing in contrast to neurotypical readers. In addition, in the visual modality, dyslexics have reduced structural connectivity between the left visual thalamus (lateral geniculate nucleus, LGN) and V5/MT, a cerebral cortex region involved in visual movement processing. Higher LGN-V5/MT connectivity in dyslexics was associated with the faster rapid naming of letters and numbers (RANln), a measure that is highly correlated with reading proficiency. We here tested two hypotheses that were directly derived from these previous findings. First, we tested the hypothesis that dyslexics have reduced structural connectivity between the left MGB and the auditory motion-sensitive part of the left planum temporale (mPT). Second, we hypothesized that the amount of left mPT-MGB connectivity correlates with dyslexics RANln scores. Using diffusion tensor imaging based probabilistic tracking we show that male adults with developmental dyslexia have reduced structural connectivity between the left MGB and the left mPT, confirming the first hypothesis. Stronger left mPT-MGB connectivity was not associated with faster RANnl scores in dyslexics, but in neurotypical readers. Our findings provide first evidence that reduced cortico-thalamic connectivity in the auditory modality is a feature of developmental dyslexia, and that it may also impact on reading related cognitive abilities in neurotypical readers

Sensory attenuation in sport and rehabilitation:perspective from research in Parkinson's disease

People with Parkinson’s disease (PD) experience motor symptoms that are affected by sensory information in the environment. Sensory attenuation describes the modulation of sensory input caused by motor intent. This appears to be altered in PD and may index important sensorimotor processes underpinning PD symptoms. We review recent findings investigating sensory attenuation and reconcile seemingly disparate results with an emphasis on task-relevance in the modulation of sensory input. Sensory attenuation paradigms, across different sensory modalities, capture how two identical stimuli can elicit markedly different perceptual experiences depending on our predictions of the event, but also the context in which the event occurs. In particular, it appears as though contextual information may be used to suppress or facilitate a response to a stimulus on the basis of task-relevance. We support this viewpoint by considering the role of the basal ganglia in task-relevant sensory filtering and the use of contextual signals in complex environments to shape action and perception. This perspective highlights the dual effect of basal ganglia dysfunction in PD, whereby a reduced capacity to filter task-relevant signals harms the ability to integrate contextual cues, just when such cues are required to effectively navigate and interact with our environment. Finally, we suggest how this framework might be used to establish principles for effective rehabilitation in the treatment of PD

Sensory, Motor and Process Skills as Compared to Symptom Severity in Adult Patients with Schizophrenia

Schizophrenia is a serious mental illness affecting millions of Americans. It is characterized by positive and negative symptoms; cognitive impairments; and sensory, motor, and process skill deficits; as well as compromised motor learning, functional difficulties, and diminished quality of life. Neuroscientists attribute the above deficits to abnormal brain development, exaggerated synaptic pruning, and neurodegenerative processes, causing disrupted connectivity and diminished plasticity in the brain, neurotransmitter dysfunction, and impaired sensory processing. Presently, there is no cure for schizophrenia. Numerous medications and rehabilitation modalities exist; however, many of the affected individuals continue to struggle daily. Recovery of these individuals implies symptom management and environmental supports to foster integration into the society and improved quality of life. Occupational therapists (OTs) utilize occupation-based assessments and interventions to evaluate and treat functional impairments in clients with various conditions, including schizophrenia, and provide their clients with environmental adaptations/modifications to enhance function. An improved understanding of the skill deficits and their relationship with schizophrenia symptomatology is necessary to refine treatment and rehabilitation for this client population, and so far, several OT scholars have attempted to research this topic. This study employed the Adolescent/Adult Sensory Profile (AASP), Assessment of Motor and Process Skills (AMPS), and Brief Psychiatric Rating Scale (BPRS) to examine the sensory, motor, and process skills of stabilized adult patients with schizophrenia spectrum disorders in relation to their symptoms. It was hypothesized that the participants would present with deficient sensory, motor, and process skills, and significant relationships would be revealed between these skill deficits and the severity of psychiatric symptoms. Analysis of the data confirmed sensory, motor, and process skill deficits in the participants. It discovered correlations between low registration and sensory sensitivity, and anxiety/depression. Relationships were also found between sensory avoidance and motor and process skill deficits. Additional findings included correlations between sensory sensitivity and sensory avoidance, between motor and process skill deficits, and between different categories of psychiatric symptoms. Study findings support the idea that schizophrenia rehabilitation necessitates addressing the skill deficits with which it comes. The concept of impaired sensory processing underlying schizophrenia symptomatology and skill deficits needs further investigation

Learning and Production of Movement Sequences: Behavioral, Neurophysiological, and Modeling Perspectives

A growing wave of behavioral studies, using a wide variety of paradigms that were introduced or greatly refined in recent years, has generated a new wealth of parametric observations about serial order behavior. What was a mere trickle of neurophysiological studies has grown to a more steady stream of probes of neural sites and mechanisms underlying sequential behavior. Moreover, simulation models of serial behavior generation have begun to open a channel to link cellular dynamics with cognitive and behavioral dynamics. Here we summarize the major results from prominent sequence learning and performance tasks, namely immediate serial recall, typing, 2XN, discrete sequence production, and serial reaction time. These populate a continuum from higher to lower degrees of internal control of sequential organization. The main movement classes covered are speech and keypressing, both involving small amplitude movements that are very amenable to parametric study. A brief synopsis of classes of serial order models, vis-à-vis the detailing of major effects found in the behavioral data, leads to a focus on competitive queuing (CQ) models. Recently, the many behavioral predictive successes of CQ models have been joined by successful prediction of distinctively patterend electrophysiological recordings in prefrontal cortex, wherein parallel activation dynamics of multiple neural ensembles strikingly matches the parallel dynamics predicted by CQ theory. An extended CQ simulation model-the N-STREAMS neural network model-is then examined to highlight issues in ongoing attemptes to accomodate a broader range of behavioral and neurophysiological data within a CQ-consistent theory. Important contemporary issues such as the nature of working memory representations for sequential behavior, and the development and role of chunks in hierarchial control are prominent throughout.Defense Advanced Research Projects Agency/Office of Naval Research (N00014-95-1-0409); National Institute of Mental Health (R01 DC02852

Functional Magnetic Resonance Imaging

"Functional Magnetic Resonance Imaging - Advanced Neuroimaging Applications" is a concise book on applied methods of fMRI used in assessment of cognitive functions in brain and neuropsychological evaluation using motor-sensory activities, language, orthographic disabilities in children. The book will serve the purpose of applied neuropsychological evaluation methods in neuropsychological research projects, as well as relatively experienced psychologists and neuroscientists. Chapters are arranged in the order of basic concepts of fMRI and physiological basis of fMRI after event-related stimulus in first two chapters followed by new concepts of fMRI applied in constraint-induced movement therapy; reliability analysis; refractory SMA epilepsy; consciousness states; rule-guided behavioral analysis; orthographic frequency neighbor analysis for phonological activation; and quantitative multimodal spectroscopic fMRI to evaluate different neuropsychological states

Early Somatosensory Processing and Crossmodal Influences

Sensory stimuli from distinct modalities are continuously linked together by the brain to create a cohesive percept of the surrounding environment—a process known as multisensory integration. Furthermore, sensory information from one modality has been shown to alter the processing of another modality. This phenomenon, now referred to as crossmodal sensory integration, has led to an abundance of research, with many studies reporting enhanced cortical responses when stimuli from different modalities (i.e., visual) occur in close temporal proximity to the onset of a tactile stimulus. Due to current COVID-19 pandemic, a time-frequency analysis (event-related spectral perturbation) of two related datasets (Faerman & Staines, 2019; Popovich & Staines, 2014) was performed in the current work. In both studies, participants were asked to attend only to crossmodal stimuli and to determine the amplitude of both the visually presented horizontal bars and vibrotactile stimuli, while electroencephalography (EEG) was recorded. Conditions involved several blocks of randomized trials with different temporal latencies between the onset of visual and tactile stimuli (i.e., 0-100ms, 100-200ms, 200-300ms). In addition, participants applied a force graded motor response using a pressure sensitive bulb, meant to represent the summation of both stimulus amplitudes. Researchers found that P50 amplitude was greatest in conditions where visual stimuli preceded tactile stimuli with later latencies of onset (0-100ms for Popovich & Staines (2014); and 200-300ms for Faerman & Staines (2019)). Given the P50 modulation reported in the studies above, the objective of the current work was to examine excitability changes of parietal cortex using de(synchronizations) in mainly the beta, alpha, and theta frequency bands, believed to occur in response to a task where both the timing and relevance of crossmodal (visual-tactile) events were manipulated. The rationale for this approach is supported by past studies that have demonstrated links between beta, alpha, and theta de(synchronizations) and a role in both sensorimotor integration and certain attentional processes (Barutchu et al., 2013; Lalo, Gilbertson, & Doyle, 2007; Siegel, Warden, & Miller). De(synchronizations) of neuronal activity are connected to the coupling and uncoupling of functional networks in the brain. Therefore, it is believed that repetitive and synchronous neuronal firing promotes the activation of functional networks because it increases the chances that neurons entrain each other in synchronous firing, and vice versa (Bastiaansen, Mazaheri, Jensen, 2012). With this background information in mind, the general hypotheses were that beta band (13-30Hz) synchronization would be greatest when a visual stimulus preceded a tactile stimulus by 100ms compared to when a tactile stimulus preceded a visual stimulus by 100ms, and that both theta and alpha synchronization would be influenced by the interaction of attention and top- down/bottom-up influences, represented by the attentional demand and the temporal relationships of the sensory processing stimuli. A one-way repeated measures analysis of variance (RM-ANOVA) confirmed a strong effect of stimulus for the theta frequency at frontal site(s), with Tukey’s post-hoc tests revealing a significant difference between the experimental condition where visual and tactile stimuli were presented simultaneously and the condition where tactile stimuli preceded visual stimuli by 100ms. A main effect of stimulus was also found for the alpha frequency range at central-parietal sites, with Tukey’s post-hoc test revealing a significant difference when visual information preceded tactile stimuli by 100-200ms and 200- 300ms. It is quite possible that the crossmodal nature of the task used in both experiments is driving, at least in part, the alpha-theta synchronizations discussed, perhaps in a similar manner to the modulations of specific ERP components (i.e., P50, P100) reported in previous studies; however further research must be conducted to provide clarity

An investigation into the neural substrates of virtue to determine the key place of virtues in human moral development

Virtues, as described by Aristotle and Aquinas, are understood as dispositions of character to behave in habitual, specific, positive ways; virtue is a critical requirement for human flourishing. From the perspective of Aristotelian-Thomistic anthropology which offers an integrated vision of the material and the rational in the human person, I seek to identify the neural bases for the development and exercise of moral virtue. First I review current neuroscientific knowledge of the capacity of the brain to structure according to experience, to facilitate behaviours, to regulate emotional responses and support goal election. Then, having identified characteristics of moral virtue in the light of the distinctions between cardinal virtues, I propose neural substrates by mapping neuroscientific knowledge to these characteristics. I then investigate the relationship between virtue, including its neurobiological features, and human flourishing. This process allows a contemporary and evidence-based corroboration for a model of moral development based on growth in virtue as understood by Aristotle and Aquinas, and a demonstration of a biological aptitude and predisposition for the development of virtue. Conclusions are drawn with respect to science, ethics, and parenting

Attention in Psychology, Neuroscience, and Machine Learning

Attention is the important ability to flexibly control limited computational resources. It has been studied in conjunction with many other topics in neuroscience and psychology including awareness, vigilance, saliency, executive control, and learning. It has also recently been applied in several domains in machine learning. The relationship between the study of biological attention and its use as a tool to enhance artificial neural networks is not always clear. This review starts by providing an overview of how attention is conceptualized in the neuroscience and psychology literature. It then covers several use cases of attention in machine learning, indicating their biological counterparts where they exist. Finally, the ways in which artificial attention can be further inspired by biology for the production of complex and integrative systems is explored

Education, Society, and the K-12 Learner

An exploration of selected components of the education profession: purpose of education. American education system, education and the legal system, child and adolescent development, and diversity. Part 1: Educational History and Policy Part 2: Educational Psychologyhttps://egrove.olemiss.edu/open/1001/thumbnail.jp