UC Santa Barbara

Performance in task switching (TS) is an important measure of cognitive flexibility. However, multiple debates in this field remain unresolved after decades of research, which prevents the development of a coherent TS theory, and limits the application of insights from TS to other fields. One of the reasons is that many TS studies included only rule-based (RB) tasks with shared sets of stimuli, responses, or both, which may lead to overlapping task sets and obscure the interpretation. In order to unravel the puzzle, the current study used distinct sets of stimuli and responses, and compared task switching across two conditions: switching between RB and procedural tasks versus between two RB tasks, and used functional Magnetic Resonance Imaging (fMRI) to observe the brain activity during task switching. Furthermore, general linear model analysis, multivariate pattern analysis and dynamic causal modeling were conducted on fMRI data to identify key features of TS neural mechanisms. The results suggested that activations in the orbitofrontal cortex showed multitask-specific patterns that can be used to identify TS components in fMRI studies. Furthermore, a set of TS principles was proposed for building TS neural computational models for future research.