Why Does the Single Neuron Activity Change from Trial to Trial during Sensory-Motor Task?

Abstract:Single neuron activities from cortical areas of a monkey were recorded while performing a sensory-motor task (a choice reaction time task). Quantitative trial-by-trial analysis revealed that the timing of peak activity exhibited large variation from trial to trial, compared to the variation in the behavioral reaction time of the task. Therefore, we developed a multi-unit dynamic neural network model to investigate the effects of structure of neural connections on the variation of the timing of peak activity. Computer simulation of the model showed that, even though the units are connected in a cascade fashion, a wide variation exists in the timing of peak activity of neurons because of parallel organization of neural network within each unit.

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Work Rhythm and Breathing Rhythm in a Repetitive Perceptual–Motor Task: The Effects of Synchronization on Performance

Proceedings of the Human Factors Society Annual Meeting ◽

10.1177/154193128703101208 ◽

1987 ◽

Vol 31 (12) ◽

pp. 1336-1340 ◽

Cited By ~ 1

Author(s):

Robert A. Henning

Keyword(s):

Reaction Time ◽

Error Rate ◽

Motor Performance ◽

Motor Task ◽

Reaction Time Task ◽

Work Rate ◽

Task Structure ◽

Rest Break ◽

Perceived Difficulty ◽

Perceptual Motor Performance

A laboratory investigation was conducted to determine if synchronization between the work rhythm and the respiratory biorhythm benefits perceptual-motor performance. The effect of work-respiratory (W–R) synchronization on reaction time, error rate, and perceived difficulty was evaluated for a visual choice reaction time task. Interstimulus intervals were chosen to induce a work rhythm. Prior to the experiment, the task was performed in a self-paced mode so that a baseline work rate could be identified for each subject. Each subject (N=22) then performed the task at 3 machine-paced work rhythms; 1) equal to the work rhythm of the baseline work rate, 2) 33% faster than the work rhythm of the baseline work rate, and 3) 33% slower than the work rhythm of the baseline work rate. Each condition consisted of two, 4 min trials separated by a brief rest break. Work rate (in responses per minute) was held constant across conditions through adjustments in task structure. Regression analysis revealed that W–R synchronization was associated with a 1% reduction in error rate and a 15 msec reduction in reaction time. These results suggest that W–R synchronization benefits perceptual–motor performance of repetitive tasks.

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Task Demand-dependent Contribution of Frontal-Sensory Cortical Projections to Attentional Behavior in Mice

10.1101/2021.04.08.439093 ◽

2021 ◽

Author(s):

Kevin J Norman ◽

Julia Bateh ◽

Priscilla Maccario ◽

Christina Cho ◽

Keaven Caro ◽

...

Keyword(s):

Reaction Time ◽

Visual Attention ◽

Reaction Time Task ◽

Serial Reaction Time Task ◽

Task Demand ◽

Neuron Activity ◽

Serial Reaction Time ◽

Top Down ◽

Serial Reaction ◽

Attentional Behavior

Top-down attention is a dynamic cognitive process that facilitates the detection of the task-relevant stimuli from our complex sensory environment. A neural mechanism capable of deployment under specific task-demand conditions would be crucial to efficiently control attentional processes and improve goal-directed attention performance in task demand-dependent manner. Previous studies have shown that frontal top-down neurons projecting from anterior cingulate area (ACA) to the visual cortex (VIS; ACAvis) are required for attentional behavior during the 5-choice serial reaction time task (5CSRTT) in mice. However, it is unknown whether the contribution of this projecting neurons is dependent on the extent of task demand. Here, we examine the differential contribution of ACAvis projection neurons to the attentional behavior in adult male mice performing two visual attention tasks of varying task demand: the 5CSRTT and 2-choice serial reaction time task (2CSRTT). We found that optogenetic suppression ACAvis projections immediately before stimulus presentation has no effect during the 2CSRTT in contrast to the impaired performance during the 5CSRTT. Fiber photometry calcium imaging of ACAvis neuron activity revealed that these neurons, which are recruited after errors during 5CSRTT, are not recruited during 2CSRTT. These results suggest that ACAvis projections are necessary only when task demand is high and that ACAvis neuron activity may not provide an error monitoring signal when task demand is low. Collectively, this frontal-sensory ACAvis projection regulates visual attention behavior during specific high task demand conditions, pointing to a flexible circuit-based mechanism for promoting attentional behavior.

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Using Neuronal Latency to Determine Sensory–Motor Processing Pathways in Reaction Time Tasks

Journal of Neurophysiology ◽

10.1152/jn.00508.2004 ◽

2005 ◽

Vol 93 (5) ◽

pp. 2974-2986 ◽

Cited By ~ 44

Author(s):

James J. DiCarlo ◽

John H. R. Maunsell

Keyword(s):

Reaction Time ◽

Behavioral Response ◽

Functional Organization ◽

Reaction Time Task ◽

Sensory Response ◽

Motor Processing ◽

Sensory Motor ◽

Processing Pathways ◽

Neurophysiological Data ◽

A New Technique

We describe a new technique that uses the timing of neuronal and behavioral responses to explore the contributions of individual neurons to specific behaviors. The approach uses both the mean neuronal latency and the trial-by-trial covariance between neuronal latency and behavioral response. Reliable measurements of these values were obtained from single-unit recordings made from anterior inferotemporal (AIT) cortex and the frontal eye fields (FEF) in monkeys while they performed a choice reaction time task. These neurophysiological data show that the responses of AIT neurons and some FEF neurons have little covariance with behavioral response, consistent with a largely “sensory” response. The responses of another group of FEF neurons with longer mean latency covary tightly with behavioral response, consistent with a largely “motor” response. A very small fraction of FEF neurons had responses consistent with an intermediate position in the sensory-motor pathway. These results suggest that this technique is a valuable tool for exploring the functional organization of neuronal circuits that underlie specific behaviors.

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Modeling Within-Person Variance in Reaction Time Data of Older Adults

GeroPsych ◽

10.1024/1662-9647/a000045 ◽

2011 ◽

Vol 24 (4) ◽

pp. 169-176 ◽

Cited By ~ 4

Author(s):

Philippe Rast ◽

Daniel Zimprich

Keyword(s):

Reaction Time ◽

Cognitive Aging ◽

Reaction Times ◽

Reaction Time Task ◽

Reaction Time Data ◽

Scale Model ◽

Time Data ◽

Time Task ◽

The Mean ◽

Second Wave

In order to model within-person (WP) variance in a reaction time task, we applied a mixed location scale model using 335 participants from the second wave of the Zurich Longitudinal Study on Cognitive Aging. The age of the respondents and the performance in another reaction time task were used to explain individual differences in the WP variance. To account for larger variances due to slower reaction times, we also used the average of the predicted individual reaction time (RT) as a predictor for the WP variability. Here, the WP variability was a function of the mean. At the same time, older participants were more variable and those with better performance in another RT task were more consistent in their responses.

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