Exploring Behavioral Oscillations with Endogenous Cues

Abstract

Attention seeks to maximize processing of potentially relevant information from a vast array of available information. One process by which does so is by covertly sampling from multiple locations in the environment even during sustained attention in one location. Previous studies have reported these sampling behaviors producing consistent, rhythmic oscillations in behavioral measures when this attentional sampling process is reset with an exogenous cue. However, the origin of rhythmicity and the subsequent behavioral oscillations are not fully understood. It has been suggested that the sampling rhythms are generated by reset events such as external spatial cues. Here, we investigated potential changes in behavioral responses produced by having an endogenous color cue direct subject attention to a specific location during covert attention task instead of an external, exogenous cue. Subject behavioral performance was measured as a function of success in recognizing a contrast change, and response time to indicate they saw a contrast change, over the cue-target delay. These behavioral responses oscillated between 4-8 Hz (theta frequency range) at the non-cued locations. Increased probability to see targets at non-cued locations (increased sampling behavior) was also associated with greater relative pupil dilation, potentially indicating neural correlates in the ongoing rhythmic sampling. Through this investigation, we demonstrated that local spatial resetting events are not necessary for the origin of rhythmic sampling and that endogenous cue can reset attentional sampling and sync behavioral oscillations.