Behavioral Performance and Neural Activation Differences Between Single- and Dual-Task Conditions: An event-related fMRI study

This study investigated the neural mechanisms of working memory during multitasking using event-related fMRI. Twelve healthy participants performed four task conditions: spatial-order working memory, delayed paired-association, and their dual-task combinations with counterbalanced order (spatialfirst or pair-first). Behavioral results revealed asymmetric dualtask interference, with spatial tasks showing greater performance decrements when performed second (accuracy reduction: 14.18%, p < 0.001). Neuroimaging data demonstrated distinct activation patterns: spatial task engaged dorsal frontoparietal networks, while pair task recruited ventral temporal regions. Dual-tasking elicited widespread activation increases, particularly in parietal lobes (up to 786 voxels), with task order modulating neural resource allocation. SVM classification confirmed distinct neural patterns for different task types. These findings reveal dynamic network reconfiguration during multitasking, with the dorsal frontoparietal network playing a central coordinating role, providing novel insights into cognitive resource allocation and has implications for optimizing human-computer interfaces.