Representation of Control and its Influence on Semantic Representation

Abstract

We tested predictions made by Guided Activation Theory (GAT) of cognitive control – that there are Task Specific Representations (TSRs) and that these representations effect goal-oriented behavior by modulating the activity of representations. We first investigated whether a common representation of control could be decoded across subjects using newly developed functional alignment tool, and whether our prediction of TSRs could be improved with the added power of more samples. In the second set of experiments, we showed that frontal areas in the brain modulate semantic representation to reflect similarity ratings of objects. In addition, we used a novel index of representational expression and its attention modulation — the spatial variance of patterns of activity identified using MVPA, for functional connectivity analysis. These results suggested that frontal cortex activity could be used to predict judgments of similarity by decoding representation of dimensions a subject was focusing on. To test this, we identified dimension-specific representations in neural data and looked at whether these representations could improve prediction of behavioral similarity judgments on a trial-by-trial basis.