Selective control of prefrontal neural timescales by parietal cortex.

Abstract

Intrinsic neural timescales quantify how long a pattern of spontaneous neuronal activity persists, thereby capturing the dynamics of its endogenous fluctuations over time. We measured the intrinsic timescales of frontal eye field (FEF) neurons and examined their changes during posterior parietal cortex (PPC) inactivation. We observed two distinct classes of FEF neurons, those with short (~25ms) or long (~100ms) timescales. Short-timescale neurons showed stronger transient visual responses, whereas long-timescale neurons exhibited stronger sustained modulation by stimulus-driven attention. During PPC inactivation, intrinsic timescales increased in both neuron types, but occurred predominantly in short-timescale neurons. In addition, PPC inactivation reduced visual and attentional modulation, particularly impairing attentional modulation in long-timescale neurons. Our results provide the first causal evidence of a selective dependence of intrinsic local neural timescales on long-range connections. These findings suggest the presence of at least two network motifs with different timescales that contribute to neuronal dynamics and functional computations in the FEF.