scholarly journals Neural codes in early sensory areas maximize fitness

2021 ◽  
Author(s):  
Jonathan Schaffner ◽  
Philippe Tobler ◽  
Todd Hare ◽  
Rafael Polania
Keyword(s):  
Nervous System ◽  
Computer Science ◽  
Sensory Processing ◽  
Sensory Information ◽  
Neural Responses ◽  
Neural Codes ◽  
Decision Behavior ◽  
Normative Framework ◽  
Specific Manner ◽  
Fitness Maximization

It has generally been presumed that sensory information encoded by a nervous system should be as accurate as its biological limitations allow. However, perhaps counter intuitively, accurate representations of sensory signals do not necessarily maximize the organism's chances of survival. To test this hypothesis, we developed a unified normative framework for fitness-maximizing encoding by combining theoretical insights from neuroscience, computer science, and economics. Initially, we applied predictions of this model to neural responses from large monopolar cells (LMCs) in the blowfly retina. We found that neural codes that maximize reward expectation---and not accurate sensory representations---account for retinal LMC activity. We also conducted experiments in humans and find that early sensory areas flexibly adopt neural codes that promote fitness maximization in a retinotopically-specific manner, which impacted decision behavior. Thus, our results provide evidence that fitness-maximizing rules imposed by the environment are applied at the earliest stages of sensory processing.

scholarly journals Increased influence of periphery on central visual processing in humans during walking

2018 ◽  
Author(s):  
Liyu Cao ◽  
Barbara Händel
Keyword(s):  
Sensory Processing ◽  
Visual Processing ◽  
Sensory Information ◽  
Human Perception ◽  
Neural Responses ◽  
Natural Behaviour ◽  
Visual Areas ◽  
Sensory Information Processing ◽  
Visual Cortical ◽  
Behavioural Evidence

AbstractCognitive processes are almost exclusively investigated under highly controlled settings while voluntary body movements are suppressed. However, recent animal work suggests differences in sensory processing between movement states by showing drastically changed neural responses in early visual areas between locomotion and stillness. Does locomotion also modulate visual cortical activity in humans and what are its perceptual consequences? Here, we present converging neurophysiological and behavioural evidence that walking leads to an increased influence of peripheral stimuli on central visual input. This modulation of visual processing due to walking is encompassed by a change in alpha oscillations, which is suggestive of an attentional shift to the periphery during walking. Overall, our study shows that strategies of sensory information processing can differ between movement states. This finding further demonstrates that a comprehensive understanding of human perception and cognition critically depends on the consideration of natural behaviour.

scholarly journals Tracking the Canonical Computations of Perceptual Processing in a Quasi-Continuous Sensory Flow

2017 ◽  
Author(s):  
Jean-Rémi King ◽  
Valentin Wyart
Keyword(s):  
Sensory Processing ◽  
Continuous Flow ◽  
Visual Stimulation ◽  
Sensory Information ◽  
Single Stimulus ◽  
Neural Responses ◽  
Neuronal Populations ◽  
Temporal Generalization ◽  
Eeg Recordings ◽  
Adaptation Phenomenon

AbstractThe canonical computations involved in sensory processing, such as neural adaptation and prediction-error signals, have mainly derived from studies investigating the neural responses elicited by a single stimulus. Here, we test whether these computations can be tracked in a quasi-continuous flow of visual stimulation, by correlating scalp electroencephalography (EEG) recordings to simulations of neuronal populations. Fifteen subjects were presented with ~5,000 visual gratings presented in rapid sequences. Our results show that we can simultaneously decode, from the EEG sensors, up to 4 visual stimuli presented sequentially. Temporal generalization and source analyses reveal that the information contained in each stimulus is processed by a “visual pipeline”: a long cascade of transient processing stages, which can overall encode multiple stimuli at once. Importantly, our data suggest that the early feedforward activity but not the late feedback responses are marked by an adaptation phenomenon. Overall, our approach demonstrates how theoretically-derived computations, as isolated in single-stimulus paradigms, can be generalized to conditions of a continuous flow of sensory information.

Neuromuscular Control of Movement

2018 ◽  
Keyword(s):  
Nervous System ◽  
Sensory Information ◽  
Neuromuscular Control ◽  
Complex Environments ◽  
Locomotor Rhythm ◽  
Motor Responses ◽  
Reflex Pathways ◽  
Local Reflex ◽  
Local Circuits ◽  
And Control

The control of movement is essential for animals traversing complex environments and operating across a range of speeds and gaits. We consider how animals process sensory information and initiate motor responses, primarily focusing on simple motor responses that involve local reflex pathways of feedback and control, rather than the more complex, longer-term responses that require the broader integration of higher centers within the nervous system. We explore how local circuits facilitate decentralized coordination of locomotor rhythm and examine the fundamentals of sensory receptors located in the muscles, tendons, joints, and at the animal’s body surface. These sensors monitor the animal’s physical environment and the action of its muscles. The sensory information is then carried back to the animal’s nervous system by afferent neurons, providing feedback that is integrated at the level of the spinal cord of vertebrates and sensory-motor ganglia of invertebrates.

scholarly journals Differential expression of five tRNA(UAGTrp) amber suppressors in Caenorhabditis elegans.

1988 ◽  
Vol 8 (9) ◽  
pp. 3627-3635 ◽  
Author(s):  
K Kondo ◽  
J Hodgkin ◽  
R H Waterston
Keyword(s):  
Nervous System ◽  
Caenorhabditis Elegans ◽  
Gene Family ◽  
Development Stage ◽  
Base Change ◽  
Wild Type ◽  
Specific Manner ◽  
Flanking Sequences ◽  
Single Base Change ◽  
The Individual

Caenorhabditis elegans has 12 tRNA(UGGTrp) genes as defined by Southern analysis. In order to evaluate the function of the individual members of this multigene family, we sought to recover amber (UAG)-suppressing mutations from reversion experiments with animals carrying amber mutations in a nervous system-affecting gene (unc-13) or a sex-determining gene (tra-3). Revertants were analyzed by Southern blot, exploiting the fact that the CCA to CTA change at the anticodon creates a new XbaI site. Five different members of the tRNATrp gene family were identified as suppressors: sup-7 X, sup-5 III, sup-24 IV, sup-28 X, and sup-29 IV. All five suppressor genes were sequenced and found to encode identical tRNA(UAGTrp) molecules with a single base change (CCA to CTA) at the anticodon compared with their wild-type counterparts. The flanking sequences had only limited homology. The relative expression of these five genes was determined by measuring the efficiencies of suppressers against amber mutations in genes affecting the nervous system, hypodermis, muscle, and sex determination. The results of these cross-suppression tests showed that the five members of the tRNA(Trp) gene family were differentially regulated in a tissue- or development stage-specific manner.

scholarly journals Sensory processing of children and students with autism spectrum disorder and typical development in relation to gender and age

2021 ◽  
Vol 20 (3) ◽  
pp. 185-201
Author(s):  
Ana Roknić ◽  
Sanja Vuković
Keyword(s):  
Autism Spectrum Disorder ◽  
Sensory Processing ◽  
Sensory Information ◽  
Autism Spectrum ◽  
Spectrum Disorder ◽  
Sensory Profile ◽  
Typical Development ◽  
Educational Plan ◽  
Gender And Age ◽  
Sensory Profiles

Introduction. Sensory processing is a neurobiological process in which a person uses their senses, sends information to an appropriate reception and processing center, and responds to environmental stimulations. Previous research has shown that sensory processing difficulties are more common among people with autism spectrum disorder than among people of the typical population. Objectives. The aim of this paper was to determine the patterns of sensory processing in subjects of the typical population and subjects with autism spectrum disorder, as well as gender and age differences in sensory profiles in these groups of subjects. Methods. Using The Child Sensory Profile 2 as the measuring instrument, the characteristics of sensory processing were examined in 120 subjects of both genders, 60 subjects with autism spectrum disorder and 60 subjects of typical development, ages three to 13 years and 11 months. Results. The obtained results show that there are differences between the two groups of respondents and that these differences occur in all nine subscales of the instrument. It was found that subjects with autismspectrumdisorder hadmore difficulty in processing sensory information compared to subjects of the typical population, especially in the domain of tactile perception. The results also show that the quality of sensory information processing in both groups of respondents improved with age. In relation to the respondents' gender, the obtained differences were significant in the domain of the total score of the instrument, in favor of the boys, but this was not observed in the measurements on all subscales. Conclusion. In accordance with the above findings, when creating an individual educational plan, it is necessary to take into account all the specifics of sensory processing of children with autism spectrum disorder.

scholarly journals Imagination der Bewegung durch Vibrationsreize – ein neuer Ansatz in der Frühmobilisation auf der Intensivstation?

2020 ◽  
Vol 26 (4) ◽  
pp. 214-218
Author(s):  
M. Lippert-Grüner ◽  
B. Bakaláø ◽  
R. Zajíèek ◽  
F. Duška
Keyword(s):  
Nervous System ◽  
Intensive Care ◽  
Pilot Study ◽  
Sensory Information ◽  
Early Mobilization ◽  
Motor Units ◽  
The Body ◽  
Entire Body ◽  
Vibration Effect ◽  
Illusory Movement

Zusammenfassung Die Optimierung der motorischen Leistung und die Einbindung und Vernetzung bisher nicht verwendeter motorischer Einheiten sowie die vermehrte Ausschüttung neurotropher Faktoren sind zentrale Mechanismen der Vibrationswirkung, die therapeutisch auf einzelne Körperteile oder den gesamten Körper angewendet werden können. Eine Möglichkeit, die Frühmobilisation bei kritisch kranken Patienten effektiver zu gestalten und immobilitätsbedingten Veränderungen vorzubeugen, könnte die Verwendung des Vibramoov™-Systems sein. Gezielt programmierte Vibrationssequenzen stimulieren hier das Nervensystem mit sensorischen Informationen, die die Empfindung einer Bewegung nachahmen (z. B. des Gehens) und somit Regenerations- und Reor-ganisationsprozesse im zentralen Nervensystem unterstützen können. Von Bedeutung ist dieser Therapieansatz vor allem bei Patienten, bei denen aufgrund ihres Zustandes konventionelle Maßnahmen nicht oder nur eingeschränkt durchgeführt werden können. Da bisher keine Erfah-rungen zur Anwendung bei intensivpflichtigen Patienten verfügbar sind, wurde eine Pilotstudie durchgeführt mit der Fragestellung, ob diese Therapieform sicher ist und im normalen Betrieb auf der Intensivstation verwendet werden kann. Die Ergebnisse der Pilotstudie mit fünf Patienten zei-gen, dass die Anwendung von Vibramoov™ zu keiner wesentlichen Veränderung kardiopulmo-naler Parameter im Sinne einer Non-Toleranz führte und im klinischen Setting gut umsetzbar war. Schlüsselwörter: Frührehabilitation, Imagination von Bewegung, Intensivstation, Vibramoov™ Imagination of movement through vibrational stimuli – a new approach to early mobilization in intensive care units? A pilot study Abstract The optimization of motor performance and the integration and networking of previously unused motor units, as well as the increased release of neurotrophic factors, are central mechanisms related to the vibration effect that can be applied therapeutically to individual parts of the body or to the entire body. One way to make early mobilization more effective in critically ill patients and to prevent changes due to immobility could be rehabilitation with functional proprioceptive stimulation, also known as “illusory movement”. Specifically programmed vibration sequences stimulate the nervous system with sensory information that mimics the sensation of movement (e. g., walking) and can thus support regeneration and reorganization processes in the central nervous system. This therapeutic approach is particularly important for patients who, due to their condition, cannot – or only to a limited extent – carry out conventional measures. Since no experience has so far been available for use in intensive care patients, we carried out a pilot study to answer the question of whether this form of therapy can be used safely and in normal operations in the intensive care unit. The results of the pilot study with 5 patients showed that the use of Vibramoov™ did not lead to any significant change in cardiopulmonary parameters in terms of non-tolerance and was easy to implement in a clinical setting. Keywords: early rehabilitation, illusory movements, ICU, functional proprio-ceptive stimulation

scholarly journals Going beyond rote auditory learning: Neural patterns of generalized auditory learning

2021 ◽  
Author(s):  
Shannon L.M. Heald ◽  
Stephen C. Van Hedger ◽  
John Veillette ◽  
Katherine Reis ◽  
Joel S. Snyder ◽  
...  
Keyword(s):  
Speech Perception ◽  
Sensory Processing ◽  
Auditory Processing ◽  
Auditory Evoked Potentials ◽  
Brain Regions ◽  
Auditory Evoked Potential ◽  
Cortical Processing ◽  
Rote Learning ◽  
Neural Responses ◽  
Auditory Learning

AbstractThe ability to generalize rapidly across specific experiences is vital for robust recognition of new patterns, especially in speech perception considering acoustic-phonetic pattern variability. Behavioral research has demonstrated that listeners are rapidly able to generalize their experience with a talker’s speech and quickly improve understanding of a difficult-to-understand talker without prolonged practice, e.g., even after a single training session. Here, we examine the differences in neural responses to generalized versus rote learning in auditory cortical processing by training listeners to understand a novel synthetic talker using a Pretest-Posttest design with electroencephalography (EEG). Participants were trained using either (1) a large inventory of words where no words repeated across the experiment (generalized learning) or (2) a small inventory of words where words repeated (rote learning). Analysis of long-latency auditory evoked potentials at Pretest and Posttest revealed that while rote and generalized learning both produce rapid changes in auditory processing, the nature of these changes differed. In the context of adapting to a talker, generalized learning is marked by an amplitude reduction in the N1-P2 complex and by the presence of a late-negative (LN) wave in the auditory evoked potential following training. Rote learning, however, is marked only by temporally later source configuration changes. The early N1-P2 change, found only for generalized learning, suggests that generalized learning relies on the attentional system to reorganize the way acoustic features are selectively processed. This change in relatively early sensory processing (i.e. during the first 250ms) is consistent with an active processing account of speech perception, which proposes that the ability to rapidly adjust to the specific vocal characteristics of a new talker (for which rote learning is rare) relies on attentional mechanisms to adaptively tune early auditory processing sensitivity.Statement of SignificancePrevious research on perceptual learning has typically examined neural responses during rote learning: training and testing is carried out with the same stimuli. As a result, it is not clear that findings from these studies can explain learning that generalizes to novel patterns, which is critical in speech perception. Are neural responses to generalized learning in auditory processing different from neural responses to rote learning? Results indicate rote learning of a particular talker’s speech involves brain regions focused on the memory encoding and retrieving of specific learned patterns, whereas generalized learning involves brain regions involved in reorganizing attention during early sensory processing. In learning speech from a novel talker, only generalized learning is marked by changes in the N1-P2 complex (reflective of secondary auditory cortical processing). The results are consistent with the view that robust speech perception relies on the fast adjustment of attention mechanisms to adaptively tune auditory sensitivity to cope with acoustic variability.

scholarly journals Neuropeptides and Behaviors: How Small Peptides Regulate Nervous System Function and Behavioral Outputs

2021 ◽  
Vol 14 ◽  
Author(s):  
Umer Saleem Bhat ◽  
Navneet Shahi ◽  
Siju Surendran ◽  
Kavita Babu
Keyword(s):  
Nervous System ◽  
Behavioral Plasticity ◽  
Environmental Changes ◽  
Sensory Information ◽  
Synaptic Activity ◽  
Small Peptides ◽  
C Elegans ◽  
Wide Range ◽  
Nervous System Function ◽  
Insight Into

One of the reasons that most multicellular animals survive and thrive is because of the adaptable and plastic nature of their nervous systems. For an organism to survive, it is essential for the animal to respond and adapt to environmental changes. This is achieved by sensing external cues and translating them into behaviors through changes in synaptic activity. The nervous system plays a crucial role in constantly evaluating environmental cues and allowing for behavioral plasticity in the organism. Multiple neurotransmitters and neuropeptides have been implicated as key players for integrating sensory information to produce the desired output. Because of its simple nervous system and well-established neuronal connectome, C. elegans acts as an excellent model to understand the mechanisms underlying behavioral plasticity. Here, we critically review how neuropeptides modulate a wide range of behaviors by allowing for changes in neuronal and synaptic signaling. This review will have a specific focus on feeding, mating, sleep, addiction, learning and locomotory behaviors in C. elegans. With a view to understand evolutionary relationships, we explore the functions and associated pathophysiology of C. elegans neuropeptides that are conserved across different phyla. Further, we discuss the mechanisms of neuropeptidergic signaling and how these signals are regulated in different behaviors. Finally, we attempt to provide insight into developing potential therapeutics for neuropeptide-related disorders.

scholarly journals Olfaction Modulates Early Neural Responses to Matching Visual Objects

2015 ◽  
Vol 27 (4) ◽  
pp. 832-841 ◽  
Author(s):  
Amanda K. Robinson ◽  
Judith Reinhard ◽  
Jason B. Mattingley
Keyword(s):  
Neural Activity ◽  
Visual Processing ◽  
Sensory Information ◽  
Neural Correlates ◽  
Neural Responses ◽  
Visual Objects ◽  
Cortical Areas ◽  
Early Visual Processing ◽  
Considerable Research ◽  
Matter Concentration

Sensory information is initially registered within anatomically and functionally segregated brain networks but is also integrated across modalities in higher cortical areas. Although considerable research has focused on uncovering the neural correlates of multisensory integration for the modalities of vision, audition, and touch, much less attention has been devoted to understanding interactions between vision and olfaction in humans. In this study, we asked how odors affect neural activity evoked by images of familiar visual objects associated with characteristic smells. We employed scalp-recorded EEG to measure visual ERPs evoked by briefly presented pictures of familiar objects, such as an orange, mint leaves, or a rose. During presentation of each visual stimulus, participants inhaled either a matching odor, a nonmatching odor, or plain air. The N1 component of the visual ERP was significantly enhanced for matching odors in women, but not in men. This is consistent with evidence that women are superior in detecting, discriminating, and identifying odors and that they have a higher gray matter concentration in olfactory areas of the OFC. We conclude that early visual processing is influenced by olfactory cues because of associations between odors and the objects that emit them, and that these associations are stronger in women than in men.

Mechanisms for generating temporal filters in the electrosensory system

1999 ◽  
Vol 202 (10) ◽  
pp. 1281-1289 ◽  
Author(s):  
G.J. Rose ◽  
E.S. Fortune
Keyword(s):  
Nervous System ◽  
Discharge Rate ◽  
Temporal Structure ◽  
Sensory Information ◽  
Gain Control ◽  
Membrane Properties ◽  
Control Mechanisms ◽  
Temporal Features ◽  
Level Of Activity ◽  
The Central Nervous System

Temporal patterns of sensory information are important cues in behaviors ranging from spatial analyses to communication. Neural representations of the temporal structure of sensory signals include fluctuations in the discharge rate of neurons over time (peripheral nervous system) and the differential level of activity in neurons tuned to particular temporal features (temporal filters in the central nervous system). This paper presents our current understanding of the mechanisms responsible for the transformations between these representations in electric fish of the genus Eigenmannia. The roles of passive and active membrane properties of neurons, and frequency-dependent gain-control mechanisms are discussed.

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