Dynamic Construction of a Coherent Attentional State in a Prefrontal Cell Population

Summary

Prefrontal cortex has been proposed to show highly adaptive information coding, with neurons dynamically allocated to processing task-relevant information. To track this dynamic allocation in monkey prefrontal cortex, we used time-resolved measures of neural population activity in a simple case of competition between target (behaviorally critical) and nontarget objects in opposite visual hemifields. Early in processing, there were parallel responses to competing inputs, with neurons in each hemisphere dominated by the contralateral stimulus. Later, the nontarget lost control of neural activity, with emerging global control by the behaviorally critical target. The speed of transition reflected the competitive weights of different display elements, occurring most rapidly when relative behavioral significance was well established by training history. In line with adaptive coding, the results show widespread reallocation of prefrontal processing resources as an attentional focus is established.

Highlights

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  Prefrontal neurons show classic properties of a limited attentional resource

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  Division of processing resources impairs accuracy of neural discriminations

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  As processing unfolds, neurons are reallocated to the most important stimuli

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  The speed and degree of reallocation depend on relative attentional weights

Abstract

Like a flexible processing resource, prefrontal cortex can respond to many kinds of information. Kadohisa et al. show how neurons in monkey prefrontal cortex are dynamically reallocated to construct a coherent attentional focus as a visual display is processed.