A Neural Circuit Model of the Striatum Resolves the Conflict between Context and Dominance Apparent in the Prefrontal Cortex

[摘要] Neural selectivity is essential to organize information in the brain. Being able to filterthe relevant information and to combine several aspects of a task is key to accomplishgoal-directed behavior. In a recent study [1], the authors recorded prefrontal neurons ofmacaque monkeys performing an attention task. The monkeys needed to respond to arelevant stimulus dimension (orientation or color, defined by a previously presented cue)to obtain a reward. Results from the study showed that prefrontal cells synchronized theiractivity at beta frequencies during stimulus presentation. Selectivity in the prefrontal cortex(PFC) to either stimulus dimension (orientation or color) was apparent because coherence atbeta frequencies was modulated by two distinct aspects: context and dominance. Contextwas correlated physiologically with a boost in coherence in the population encoding therelevant dimension. In addition, neural recordings also showed a dominance of orientationagainst color. In orientation trials, context and dominance modulations were aligned fororientation-selective cells, which were behaviorally correlated with shorter response times.In contrast, in color trials no apparent difference was present between the patterns of activityof color- and orientation-selective cells in PFC due to the misalignment between contextand dominance, even though monkeys performed the task similarly well. Interestingly, thestudy also reported the presence of pre-stimulus alpha-oscillatory activity in orientationselective cells, which appeared at the cue onset of the color trials.

[关键词] context-dependent decision-making;dominance of inhibitory control;corticostriatal processing;neural representation;oscillatory activity