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An exploration of the level of performance on neuropsychological tests, pathognomic signs, and patterns of performance of brain-injured adults and children is highlighted. A review of their performances on the two sides of their bodies on motor and sensory perceptual measures is featured. Methods for estimating their levels of functioning are discussed. Moreover, the crucial distinction between lower-level sensory motor and higher-level cortical function abilities related to neuropsychological development and patterns of brain injury is highlighted. In addition, the crucial distinction between sensory motor and higher cortical function abilities related to neuropsychological development and patterns of brain injury will be addressed. This chapter discusses the clinical neuropsychological interpretation of the data of brain-injured adults and children. The major focus is upon Ralph M. Reitan’s methods of inference as applied to brain-injured individuals.

Functional connectivity of the resting-state (RS) brain is a vehicle to study brain dysconnectivity aspects of diseases such as schizophrenia and bipolar. Methods that are developed to measure functional connectivity are based on the underlying hypotheses regarding the actual nature of RS-connectivity including evidence of temporally dynamic versus static RS-connectivity and evidence of frequency-specific versus hemodynamically-driven connectivity over a wide frequency range. This study is derived by these observations of variation of RS-connectivity in temporal and frequency domains and evaluates such characteristics of RS-connectivity in clinical population and jointly in temporal and frequency domains (the spectro-temporal domain). We base this study on the hypothesis that by studying functional connectivity of schizophrenia patients and comparing it to the one of healthy controls in the spectro-temporal domain we might be able to make new observations regarding the differences and similarities between diseased and healthy brain connectivity and such observations could be obscured by studies which investigate such characteristics separately. Interestingly, our results include, but are not limited to, a spectrally localized (mostly mid-range frequencies) modular dynamic connectivity pattern in which sensory motor networks are anti-correlated with visual, auditory and sub-cortical networks in schizophrenia, as well as evidence of lagged dependence between default-mode and sensory networks in schizophrenia. These observations are unique to the proposed augmented domain of connectivity analysis. We conclude this study by arguing not only resting-state connectivity has structured spectro-temporal variability, but also that studying properties of connectivity in this joint domain reveals distinctive group-based differences and similarities between clinical and healthy populations., Highlights • RS-connectivity of Schizophrenia and healthy is studied in domain of time and frequency. • Dynamic connectivity is now superposition of connectivities with unique frequencies. • Augmented domain reveals novel connectivity patterns unique to schizophrenia/healthy.

Somatosensory feedback is the next step in brain computer interface (BCI). Here, we compare three cortical stimulating array modalities for generating somatosensory percepts in BCI. We compared human subjects with either a 64-channel “mini”-electrocorticography grid (mECoG; 1.2-mm diameter exposed contacts with 3-mm spacing, N = 1) over the hand area of primary somatosensory cortex (S1), or a standard grid (sECoG; 1.5-mm diameter exposed contacts with 1-cm spacing, N = 1), to generate artificial somatosensation through direct electrical cortical stimulation. Finally, we reference data in the literature from a patient implanted with microelectrode arrays (MEA) placed in the S1 hand area. We compare stimulation results to assess coverage and specificity of the artificial percepts in the hand. Using the mECoG array, hand mapping revealed coverage of 41.7% of the hand area versus 100% for the sECoG array, and 18.8% for the MEA. On average, stimulation of a single electrode corresponded to sensation reported in 4.42 boxes (range 1–11 boxes) for the mECoG array, 19.11 boxes (range 4–48 boxes) for the sECoG grid, and 2.3 boxes (range 1–5 boxes) for the MEA. Sensation in any box, on average, corresponded to stimulation from 2.65 electrodes (range 1–5 electrodes) for the mECoG grid, 3.58 electrodes for the sECoG grid (range 2–4 electrodes), and 11.22 electrodes (range 2–17 electrodes) for the MEA. Based on these findings, we conclude that mECoG grids provide an excellent balance between spatial cortical coverage of the hand area of S1 and high-density resolution.

Anorectal disorders (ADs) with symptoms of fecal incontinence (FI) and impaired evacuation are highly prevalent and represent a significant socio-economic burden. Symptoms alone do not provide sufficient information on the underlying pathology, therefore in cases where symptoms are refractory to treatment anorectal testing is indicated. The continence mechanism is complex and requires a complex interaction of involuntary and voluntary muscle activity, motor and sensory motor pathways, as well as a functioning rectal reservoir. The armamentarium of diagnostic tools in ADs has grown over recent years to include high-resolution anorectal manometry, EndoFLIP for the assessment of anal distensibility, and novel imaging technologies, such as magnetic resonance imaging. These innovations have improved our understanding of anorectal structure and function. However, no single test can diagnose FI and an evacuatory disorder on its own and current guidelines recommend a series of tests to assess anorectal structure as well as sensory and motor function.

Arsenic (As) is one of the most toxic naturally occurring contaminants in the environment. The major source of human exposure to inorganic As (iAs) is through contaminated drinking water. Although both genotoxicity and carcinogenicity derived from this metalloid have been thoroughly studied, the effects of iAs on the development and function of the central nervous system (CNS) have received less attention and only a few studies have focused on neurobehavioral effects. Thus, in order to characterize developmental and behavioral alterations induced by iAs exposure, pregnant Wistar rats were exposed to 0.05 and 0.10 mg/L iAs through drinking water during gestation and lactation. Sensory-motor reflexes in each pup were analyzed and the postnatal day when righting reflex, cliff aversion and negative geotaxis were observed was recorded. Functional Observational Battery (FOB) and locomotor activity in an open field were assessed in 90-day-old offspring. Results show that rats exposed to low iAs concentrations through drinking water during early development evidence a delay in the development of sensory-motor reflexes. Both FOB procedure and open-field tests showed a decrease in locomotor activity in adult rats. This study reveals that exposure to the above-mentioned iAs concentrations produces dysfunction in the CNS mechanisms whose role is to regulate motor and sensory development and locomotor activity., Centro de Investigación y Desarrollo en Criotecnología de Alimentos

This article reviews the sensory-motor behavioral progression of typically developing human infants from birth to about 1 year of age. The authors focus on the different sensory-motor achievements that each period of development requires as infants progress toward the acquisition of upright locomotion and the acquisition of adaptive goal-directed reaching and grasping behaviors. They show that the formation and mastery of these fundamental motor skills in infancy does not follow in a linear process, but rather a complex, whole-body, and experience-dependent one needing the reciprocal integration and mutual reorganization of multiple competing developing systems.

The assessment of changes in sensory-motor function in clinical research presents a unique set of difficulties. Clinimetrics is the science of measurement as related to the identification of a clinical disorder, the tracing of the progression of the condition under study, and calculation of its impact. The selection of appropriate measures for clinical studies of sensory-motor function must consider validity, sensitivity, specificity, responsiveness, reliability, and feasibility. Reasonable measures of motor function in clinical research include manual examination of muscle strength, electrophysiology, functional scales, patient-reported outcomes (e.g., quality of life), and for severe conditions such as ALS, survival. The assessment of sensory function includes targeted electrophysiology and QOL, as well as more focused measures such as quantitative sensory testing and the scoring of positive symptoms. Each individual measure and each combination of endpoints has its strengths and limitations.

El pdf del artículo es la versión pre-print.-- et al., This paper formalises Object-Action Complexes (OACs) as a basis for symbolic representations of sensory-motor experience and behaviours. OACs are designed to capture the interaction between objects and associated actions in artificial cognitive systems. This paper gives a formal definition of OACs, provides examples of their use for autonomous cognitive robots, and enumerates a number of critical learning problems in terms of OACs., The research leading to these results received funding from the European Union through the Sixth Framework PACO-PLUS project (IST-FP6-IP-027657) and the Seventh Framework XPERIENCE project (FP7/2007-2013, Grant No. 270273).

Publisher Summary Sensory motor therapy uses mindfulness-based techniques to increase awareness and acceptance of body sensations and impulses. This technique encourages an increased awareness of the body, particularly the level of arousal, changes in voice, breath, movements, and posture associated with states of wellbeing. A language for describing body states emerges as the therapist notices changes in these. Interventions teach mindfulness, focusing the client on the present experience of core organizers: thoughts, emotions, movement, sensation, and the five senses perceptions with a specific goal of enhancing self-modulation. Mobilization is associated with states of compassion, acceptance, exploration, and self-care. The therapist notices, celebrates, and builds on emerging skills as clients become more able to listen and respond to the body, gradually shifting to a state of wellbeing. These skills are necessary to reduce the dis-regulation associated with very painful memories or emotions. It follows that these techniques may be particularly useful in those who have suffered sexual trauma or who have extreme physical dis-regulation due to eating disorder.

Publisher Summary This chapter reviews that the goal of brain surgery is to remove as much pathological tissue as possible, yet preserve brain function. Brain surgery in or near eloquent cortex requires understanding of the anatomic localization of eloquent brain function in these regions prior to resection of brain tissue. It discusses that brain mapping with direct cortical electrical stimulation essentially involves assessing whether electrical stimulation to a small region of cortical surface results in a neurological change in the patient, such as a movement or speech arrest. The chapter reviews that the reliability of electrocortical stimulation mapping for predicting the postoperative functional outcomes depends on whether the stimulation used is sufficient to alter the cortical activity, the effects of stimulation are focal, and the appropriate task is chosen to test the function of the cortical region stimulated. Direct cortical stimulation for brain mapping can be done extraoperatively using implanted subdural electrodes, as is often done in patients undergoing an epilepsy surgery evaluation or intraoperatively. Both the techniques generally employ the same principles toward mapping the brain function but differ somewhat with regard to their benefits and limitations. This chapter focuses on the technical aspects of intraoperative brain mapping using direct cortical stimulation.

The generation of goal-directed movements requires the solution of many difficult computational problems. In addition to generating the forces needed for movement there are a number of essentially geometric problems. Among these are transformations from extrinsic to intrinsic reference frames, removing under-specification due to excess degrees of freedom and path multiplicity, and error correction. There are no current motor control computational models that address these issues in the context of realistic arm movement with redundant degrees of freedom. In this chapter, we describe a geometric stage between sensory input and physical execution. The geometric stage determines movement paths without reference to forces. It is implemented with a gradient technique that can generate movement paths online. The model is demonstrated by simulating a seven degree of freedom arm that moves in three-dimensional space. Simulated orientation-matching movements generated by the model are compared with human experimental movement data to assess the validity of several of the model's behavioral predictions.

This paper addresses the issue of continual, incremental development of behaviors in reactive agents. The reactive agents are neural-network based and use reinforcement learning techniques. A continually developing system is one that is constantly capable of extending its repertoire of behaviors. An agent increases its repertoire of behaviors in order to increase its performance in and understanding of its environment. Continual development requires an unlimited growth potential; that is, it requires a system that can constantly augment current behaviors with new behaviors, perhaps using the current ones as a foundation for those that come next. It also requires a process for organizing behaviors in meaningful ways and a method for assigning credit properly to sequences of indefinitely long-lasting behaviors. The solution proposed here is hierarchical and bottom up. I introduce a new kind of neuron (termed a “bion―), whose characteristics permit it to be automatically constructed into sensory-motor hierarchies as determined by experience. The bion is being developed to resolve the problems of incremental growth, temporal history limitation, network organization, and credit assignment among component behaviors.

This article suggests a psychophysiological foundation for cognitive theory, and more generally for goal-oriented or purposive behavior. Of all my articles, this is the one which drives deepest into uncharted territory. I say this partly because new implications of my own concepts and constructions in the article are still crystallizing in my mind.

Publisher Summary This chapter discusses adaptation in the oculomotor system. Adaptive modification in oculomotor behavior is observed in many ecological and artificial conditions. There are a number of different processes that contribute to adaptation. One of them is a physiological mechanism that consists of modification of the gain and phase of sensory motor loops. This is similar to parameter adjustments occurring in servo-controlled systems and is modeled using the theoretical framework of linear systems theory. The oculomotor system is suited for such description because it is organized in functionally identifiable subsystems. These subsystems have either a stabilizing or an orienting role and are divided arbitrarily into reflexes. The general similarity between servo-controlled systems and oculomotor networks has led neurophysiologists and psychologists to concentrate on modifications occurring within each subsystem and search for detailed neuronal transformations that could explain the whole behavior by synaptic plasticity. The chapter also discusses an alternate approach that uses other mechanisms of adaptation.

Publisher Summary This chapter discusses the human frontal lobe function in sensory-motor association. It illustrates an essential character of frontal lobe function—abnormal disturbances have no general importance provided that they affect only a very limited zone of cortex. The chapter describes the actual discoveries relating to frontal lobe function. It describes the correlations between the contingent negative variation (CNV) or expectancy wave and the psychological situation in adults. CNV grows slowly over the first few dozen presentations of associated stimuli after instructions to respond to the imperative stimuli. The CNV persists indefinitely as long as the subject retains an interest and concern with the adult's response. The probabilistic relation between stimulus association and the CNV in the brain is best demonstrated by diluting the probability of association with a known proportion of unreinforced conditional stimuli. With its immensely rich connections to all sources of sensory information, its capacity for economical storage and cross-correlation of information, and its exquisite sensitivity to subtle shades of social and semantic implication, the frontal cortex provides the essential link between the elementary stages of structural evolution and the present phase of psychosocial development of the human organism.