Neural Sources and Underlying Mechanisms of Neural Responses to Heartbeats, and their Role in Bodily Self-consciousness: An Intracranial EEG Study

Response inhibition is frequently examined using visual go/no-go tasks. Recently, the auditory go/no-go paradigm has been also applied to several clinical and aging populations. However, age-related changes in the neural underpinnings of auditory go/no-go tasks are yet to be elucidated. We used magnetoencephalography combined with distributed source imaging methods to examine age-associated changes in neural responses to auditory no-go stimuli. Additionally, we compared the performance of high- and low-performing older adults to explore differences in cortical activation. Behavioral performance in terms of response inhibition was similar in younger and older adult groups. Relative to the younger adults, the older adults exhibited reduced cortical activation in the superior and middle temporal gyrus. However, we did not find any significant differences in cortical activation between the high- and low-performing older adults. Our results therefore support the hypothesis that inhibition is reduced during aging. The variation in cognitive performance among older adults confirms the need for further study on the underlying mechanisms of inhibition.

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Neural computations in children’s third-party interventions are modulated by their parents’ moral values

npj Science of Learning ◽

10.1038/s41539-021-00116-5 ◽

2021 ◽

Vol 6 (1) ◽

Author(s):

Minkang Kim ◽

Jean Decety ◽

Ling Wu ◽

Soohyun Baek ◽

Derek Sankey

Keyword(s):

Moral Values ◽

Early Years ◽

Third Party ◽

Social Cooperation ◽

Neural Responses ◽

Parent Survey ◽

Neural Computations ◽

Interaction Experiment ◽

Underlying Mechanisms ◽

Deliberative Processes

AbstractOne means by which humans maintain social cooperation is through intervention in third-party transgressions, a behaviour observable from the early years of development. While it has been argued that pre-school age children’s intervention behaviour is driven by normative understandings, there is scepticism regarding this claim. There is also little consensus regarding the underlying mechanisms and motives that initially drive intervention behaviours in pre-school children. To elucidate the neural computations of moral norm violation associated with young children’s intervention into third-party transgression, forty-seven preschoolers (average age 53.92 months) participated in a study comprising of electroencephalographic (EEG) measurements, a live interaction experiment, and a parent survey about moral values. This study provides data indicating that early implicit evaluations, rather than late deliberative processes, are implicated in a child’s spontaneous intervention into third-party harm. Moreover, our findings suggest that parents’ values about justice influence their children’s early neural responses to third-party harm and their overt costly intervention behaviour.

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Computational Modelling of Cerebellar Magnetic Stimulation: The Effect of Washout

Lecture Notes in Computer Science - Brain-Inspired Computing ◽

10.1007/978-3-030-82427-3_3 ◽

2021 ◽

pp. 35-46

Author(s):

Alberto Antonietti ◽

Claudia Casellato ◽

Egidio D’Angelo ◽

Alessandra Pedrocchi

Keyword(s):

Washout Period ◽

Magnetic Stimulation ◽

Computational Models ◽

Computational Modelling ◽

Mechanistic Explanation ◽

Neural Responses ◽

External Stimulation ◽

Associative Conditioning ◽

Underlying Mechanisms ◽

The Brain

AbstractNowadays, clinicians have multiple tools that they can use to stimulate the brain, by means of electric or magnetic fields that can interfere with the bio-electrical behaviour of neurons. However, it is still unclear which are the neural mechanisms that are involved and how the external stimulation changes the neural responses at network-level. In this paper, we have exploited the simulations carried out using a spiking neural network model, which reconstructed the cerebellar system, to shed light on the underlying mechanisms of cerebellar Transcranial Magnetic Stimulation affecting specific task behaviour. Namely, two computational studies have been merged and compared. The two studies employed a very similar experimental protocol: a first session of Pavlovian associative conditioning, the administration of the TMS (effective or sham), a washout period, and a second session of Pavlovian associative conditioning. In one study, the washout period between the two sessions was long (1 week), while the other study foresaw a very short washout (15 min). Computational models suggested a mechanistic explanation for the TMS effect on the cerebellum. In this work, we have found that the duration of the washout strongly changes the modification of plasticity mechanisms in the cerebellar network, then reflected in the learning behaviour.

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Adaptation decorrelates shape representations

10.1101/249045 ◽

2018 ◽

Author(s):

Marcelo G. Mattar ◽

Maria Olkkonen ◽

Russell A. Epstein ◽

Geoffrey K. Aguirre

Keyword(s):

Shape Space ◽

Behavioral Experiment ◽

Visual Adaptation ◽

Perceptual Discrimination ◽

Neural Responses ◽

Shape Representations ◽

Neural Representations ◽

Sensory History ◽

Shape Class ◽

Underlying Mechanisms

AbstractPerception and neural responses are modulated by sensory history. Visual adaptation, an example of such an effect, has been hypothesized to improve stimulus discrimination by decorrelating responses across a set of neural units. While a central theoretical model, behavioral and neural evidence for this theory is limited and inconclusive. Here, we use a parametric 3D shape-space to test whether adaptation decorrelates shape representations in humans. In a behavioral experiment with 20 subjects, we find that adaptation to a shape class improves discrimination of subsequently presented stimuli with similar features. In a BOLD fMRI experiment with 10 subjects we observe that adaptation to a shape class decorrelates the multivariate representations of subsequently presented stimuli with similar features in object-selective cortex. These results support the long-standing proposal that adaptation improves perceptual discrimination and decorrelates neural representations, offering insights into potential underlying mechanisms.

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Feedback optimizes neural coding and perception of natural stimuli

eLife ◽

10.7554/elife.38935 ◽

2018 ◽

Vol 7 ◽

Cited By ~ 12

Author(s):

Chengjie G Huang ◽

Michael G Metzen ◽

Maurice J Chacron

Keyword(s):

Neural Coding ◽

Spectral Power ◽

Tuning Curve ◽

Weakly Electric Fish ◽

Neural Responses ◽

Low Frequencies ◽

Natural Stimuli ◽

Descending Input ◽

Underlying Mechanisms ◽

High Pass

Growing evidence suggests that sensory neurons achieve optimal encoding by matching their tuning properties to the natural stimulus statistics. However, the underlying mechanisms remain unclear. Here we demonstrate that feedback pathways from higher brain areas mediate optimized encoding of naturalistic stimuli via temporal whitening in the weakly electric fish Apteronotus leptorhynchus. While one source of direct feedback uniformly enhances neural responses, a separate source of indirect feedback selectively attenuates responses to low frequencies, thus creating a high-pass neural tuning curve that opposes the decaying spectral power of natural stimuli. Additionally, we recorded from two populations of higher brain neurons responsible for the direct and indirect descending inputs. While one population displayed broadband tuning, the other displayed high-pass tuning and thus performed temporal whitening. Hence, our results demonstrate a novel function for descending input in optimizing neural responses to sensory input through temporal whitening that is likely to be conserved across systems and species.

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Imaging of obsessive–compulsive disorder

New Oxford Textbook of Psychiatry ◽

10.1093/med/9780198713005.003.0097 ◽

2020 ◽

pp. 1003-1010

Author(s):

Rebbia Shahab ◽

Emily R. Stern

Keyword(s):

Obsessive Compulsive Disorder ◽

Cognitive Neuroscience ◽

Small Body ◽

Reward Processing ◽

Neural Responses ◽

Obsessive Compulsive ◽

Brain Functioning ◽

Compulsive Disorder ◽

Underlying Mechanisms ◽

Monitoring Response

Neuroimaging has allowed researchers to measure the complexity of brain functioning in ways never before possible. The cognitive neuroscience approach investigates neural responses to cognitive–emotional stimuli, which has yielded critical insights into the mechanisms of psychiatric disorders. This chapter reviews some of the major findings from studies using a cognitive neuroscience approach to investigating obsessive–compulsive disorder (OCD). Focusing on studies of conflict and error monitoring, response inhibition, switching and reversal, reward processing, and decision-making, the chapter evaluates the consistency of results and interprets findings within the context of OCD symptoms. The chapter concludes by discussing the small body of work comparing brain functioning between different OCD subtypes, which highlights the importance of considering the heterogeneity of the disorder when designing and interpreting studies. Although further research is needed, this work sheds considerable light on the underlying mechanisms of OCD, which could be targeted by future strategies for intervention and prevention.

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Classification of taste responses in brain stem: membership in fuzzy sets

Journal of Neurophysiology ◽

10.1152/jn.1994.71.6.2139 ◽

1994 ◽

Vol 71 (6) ◽

pp. 2139-2150 ◽

Cited By ~ 19

Author(s):

R. P. Erickson ◽

P. M. Di Lorenzo ◽

M. A. Woodbury

Keyword(s):

Fuzzy Set ◽

Published Data ◽

Classification Methods ◽

Neural Responses ◽

Temporal Course ◽

Fuzzy Set Analysis ◽

Grade Of Membership ◽

Underlying Mechanisms ◽

Mathematical Process

1. Classification methods in sensory systems in general, and gustation in particular, tend to place each of the relevant objects, such as stimuli or neurons, into one class each. Some of these methods are based on the responsiveness of neurons to various stimuli; in these, each group must contain a variety of nonidentical members because of the individuality of each neuron or stimulus. 2. The “fuzzy” set method is appropriate for more accurate classification in such heterogeneous populations. In this method each member is given graded membership in several sets rather than membership in only one set. In the present paper we subjected previously published data on the responses of individual taste neurons to a variety of stimuli to fuzzy set analysis. 3. We found that the amounts of response of 46 neurons in the solitary nucleus of the rat to NaCl, HCl, sucrose, quinine HCl, and KCl could accurately be accounted for by giving each a grade of membership in three sets; the same held in the parabrachial nucleus of the rat for the responses of 41 neurons to the first four of these stimuli. The response was calculated as the sum of the products of the stimulus times neuron ratings in each set. 4. Temporal patterns of response have often been related, but with only moderate success, to the identity of the stimulus or neuron. These patterns could be accurately accounted for with the present method. Each of the products of designated parts of the stimulus ratings times the neuron ratings gave the basis for accurate description of the temporal course of the response of each neuron to each stimulus. 5. This method appears to account for the varieties of amount and temporal pattern of response of taste neurons with a simple mathematical process of few parameters. This suggests that within the known complexities of receptor mechanisms and mechanisms of neural processing, the neural message is reduced to a rather simple form. 6. The fuzzy set approach, which is based on disclosing underlying sets rather than placement of heterogeneous members into one of several essentialistic groups, may be useful in disclosure of the underlying mechanisms producing the neural responses in taste.

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The limits of human performance

Essays in Biochemistry ◽

10.1042/bse0440011 ◽

2008 ◽

Vol 44 ◽

pp. 11-26 ◽

Cited By ~ 14

Author(s):

Ralph Beneke ◽

Dieter Böning

Keyword(s):

Human Performance ◽

Safety Margin ◽

Afferent Input ◽

Metabolic Energy ◽

Human Organism ◽

Mechanical Resistance ◽

As Doping ◽

Gene And Protein Expression ◽

Underlying Mechanisms ◽

Biochemical Research

Human performance, defined by mechanical resistance and distance per time, includes human, task and environmental factors, all interrelated. It requires metabolic energy provided by anaerobic and aerobic metabolic energy sources. These sources have specific limitations in the capacity and rate to provide re-phosphorylation energy, which determines individual ratios of aerobic and anaerobic metabolic power and their sustainability. In healthy athletes, limits to provide and utilize metabolic energy are multifactorial, carefully matched and include a safety margin imposed in order to protect the integrity of the human organism under maximal effort. Perception of afferent input associated with effort leads to conscious or unconscious decisions to modulate or terminate performance; however, the underlying mechanisms of cerebral control are not fully understood. The idea to move borders of performance with the help of biochemicals is two millennia old. Biochemical findings resulted in highly effective substances widely used to increase performance in daily life, during preparation for sport events and during competition, but many of them must be considered as doping and therefore illegal. Supplements and food have ergogenic potential; however, numerous concepts are controversially discussed with respect to legality and particularly evidence in terms of usefulness and risks. The effect of evidence-based nutritional strategies on adaptations in terms of gene and protein expression that occur in skeletal muscle during and after exercise training sessions is widely unknown. Biochemical research is essential for better understanding of the basic mechanisms causing fatigue and the regulation of the dynamic adaptation to physical and mental training.

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Orienting and Focusing in Voluntary and Involuntary Visuospatial Attention Conditions

Journal of Psychophysiology ◽

10.1027/0269-8803/a000010 ◽

2010 ◽

Vol 24 (3) ◽

pp. 198-209 ◽

Cited By ~ 8

Author(s):

Yan Wang ◽

Jianhui Wu ◽

Shimin Fu ◽

Yuejia Luo

Keyword(s):

Gain Control ◽

Event Related Potentials ◽

Stimulus Onset ◽

Orientation Discrimination ◽

Involuntary Attention ◽

Attention Condition ◽

Voluntary Attention ◽

Visual Spatial ◽

Related Potentials ◽

Underlying Mechanisms

In the present study, we used event-related potentials (ERPs) and behavioral measurements in a peripherally cued line-orientation discrimination task to investigate the underlying mechanisms of orienting and focusing in voluntary and involuntary attention conditions. Informative peripheral cue (75% valid) with long stimulus onset asynchrony (SOA) was used in the voluntary attention condition; uninformative peripheral cue (50% valid) with short SOA was used in the involuntary attention condition. Both orienting and focusing were affected by attention type. Results for attention orienting in the voluntary attention condition confirmed the “sensory gain control theory,” as attention enhanced the amplitude of the early ERP components, P1 and N1, without latency changes. In the involuntary attention condition, compared with invalid trials, targets in the valid trials elicited larger and later contralateral P1 components, and smaller and later contralateral N1 components. Furthermore, but only in the voluntary attention condition, targets in the valid trials elicited larger N2 and P3 components than in the invalid trials. Attention focusing in the involuntary attention condition resulted in larger P1 components elicited by targets in small-cue trials compared to large-cue trials, whereas in the voluntary attention condition, larger P1 components were elicited by targets in large-cue trials than in small-cue trials. There was no interaction between orienting and focusing. These results suggest that orienting and focusing of visual-spatial attention are deployed independently regardless of attention type. In addition, the present results provide evidence of dissociation between voluntary and involuntary attention during the same task.

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Response Interference as a Mechanism Underlying Implicit Measures

European Journal of Psychological Assessment ◽

10.1027/1015-5759.24.4.218 ◽

2008 ◽

Vol 24 (4) ◽

pp. 218-225 ◽

Cited By ~ 28

Author(s):

Bertram Gawronski ◽

Roland Deutsch ◽

Etienne P. LeBel ◽

Kurt R. Peters

Keyword(s):

Task Performance ◽

Psychological Research ◽

Implicit Measures ◽

Mediation Model ◽

Response Interference ◽

Relevant Evidence ◽

Moderated Mediation Model ◽

Stimulus Features ◽

Underlying Mechanisms

Over the last decade, implicit measures of mental associations (e.g., Implicit Association Test, sequential priming) have become increasingly popular in many areas of psychological research. Even though successful applications provide preliminary support for the validity of these measures, their underlying mechanisms are still controversial. The present article addresses the role of a particular mechanism that is hypothesized to mediate the influence of activated associations on task performance in many implicit measures: response interference (RI). Based on a review of relevant evidence, we argue that RI effects in implicit measures depend on participants attention to association-relevant stimulus features, which in turn can influence the reliability and the construct validity of these measures. Drawing on a moderated-mediation model (MMM) of task performance in RI paradigms, we provide several suggestions on how to address these problems in research using implicit measures.

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