Finding and classifying the different cognitive stages in dual tasks

Abstract

This study investigates the neural processes involved in dual-task performance, specifically focusing on the psychological refractory period (PRP) effect. The central bottleneck theory, resource sharing theory, and response initiation theory are examined to understand how the brain manages concurrent tasks. Using EEG data from participants performing a flanker task and a pitch tone task with varying stimulus onset asynchronies (SOAs), HMP is applied to detect cognitive stages. The findings indicate that brain stages remain consistent across conditions, supporting the central bottleneck theory. The results show that the PRP effect is attributable to a bottleneck occurring before the central processing stage, with delays observed when tasks overlap (i.e. short SOA). Specifically, the second stage of Task 2 exhibited a significant increase in duration under short SOA conditions, indicating cognitive slack. Additionally, voltage levels within the central processing stage remained relatively stable, further supporting the central bottleneck theory over the resource sharing theory.