Poster B123, Sunday, March 25, 8:00-10:00 am, Exhibit Hall C
Dissociating Components of Multitasking Using HD-tDCS
Francesca Raileanu1, Thomas McWilliams1, Geoffrey Genova1, Scott Mongold1, Morgan Taylor1, Jasper Park1, Anisha Jain1, Isabella Montoya1, Joseph Pajka1, Erika Hussey1,2, Nathan Ward1; 1Tufts University, 2Natick Soldier Research, Development, and Engineering Center
Multitasking is a common cognitive activity that often leads to performance declines, presenting a need to understand how to offset errors. We investigated the efficacy of transcranial direct current stimulation (tDCS) to selectively influence sub-processes of multitasking, including dividing attention between tasks, or dual-tasking (DT), and switching between tasks, or task-switching (TS). Participants (N=24) received tDCS as they completed a novel task that parametrically manipulated TS and DT demands. Using neuronavigation models, we developed high-definition (HD-)tDCS montages that delivered electric current to mutually exclusive neural regions that support TS and DT demands (based on functional neuroimaging results from another study using the same task). All participants completed four tDCS sessions: anodal over TS areas, anodal over DT areas, anodal over TS+DT areas, and sham tDCS over TS+DT areas. Additionally, we tested montages that either maximized focality for each condition while allowing stimulus intensity to vary, or equalized stimulus intensity across conditions while varying focality. A mixed ANOVA of Montage Type (2) x Stimulation Type (4) x TS Demand (2) x DT Demand (2) revealed a three-way interaction between Stimulation Type, TS Demand, and DT Demand, suggesting that HD-tDCS models targeting neural resources reputed to support TS and DT demands lead to changes in TS and DT abilities. Furthermore, we found no interactive effects of Montage Type, indicating little relative benefit to selecting montages that prioritize focality versus intensity. Together, these results offer initial evidence that neuronavigation-informed tDCS montages hold promise for mitigating performance declines associated with sub-processes of multitasking.
Topic Area: EXECUTIVE PROCESSES: Goal maintenance & switching