Effects of overt and covert attention on decision-making dynamics in prefrontal cortex

Abstract

Value-based decision-making is a dynamic and idiosyncratic process which requires appraising the value of options and comparing the values to select the best choice. An emerging view of orbitofrontal cortex (OFC) is that it achieves this by representing values serially during deliberation, alternating back-and-forth between transient states that encode the value of different options. While the time spent in each value state is known to reflect choice behavior, the source of the alternating dynamics remains unclear. One possibility is that fluctuations in value may be driven by attentional shifts between the choice options. Conversely, value dynamics in OFC may be generated locally, enabling OFC value signals to influence decision-making independently from attention. To test these hypotheses, we recorded from OFC and lateral prefrontal cortex (LPFC), a major attentional area in prefrontal cortex, to determine whether their population-level activity correlated in a manner consistent with crosstalk between neuronal systems involved in value and spatial attention. We found that OFC and LPFC selectively encoded option values and spatial locations, respectively, reflecting their specialized roles in cognition. Despite this functional dissociation, both OFC and LPFC dynamics were strongly affected by overt attention: which caused the value and spatial location of the fixated option to be represented at the same time. Additionally, fluctuations in the encoding strength of value in OFC and space in LPFC were temporally correlated above and beyond the effect of gaze, reflecting the effect of covert attention.