Multitasking without task switching

Previous studies on multitasking reported inconsistent results about correlations between multitasking experiences and task switching ability. To resolve this inconsistency, some researchers suggested two strategies for multitasking: shifting attention between two tasks (task switching) and distributing attention to both tasks. In a daily multitasking situation, people could perform one main task while partially paying attention to smartphone notifications. This situation is likely to involve the latter strategy (i.e., distributing attention to the main task and the smartphone). Thus, we predict that practical multitasking ability would correlate with people’s ability to distribute attention to multiple tasks/stimuli. In the present study, we developed a novel task that measured practical multitasking ability, and investigated whether this ability correlated with attention distribution ability. In addition, we measured participants’ multitasking experiences using the Media Use Questionnaire (MUQ; Ophir et al., 2009) and tested whether MUQ scores correlated with multitasking ability. In the practical multitasking task, participants saw a sequence of pictures in the center and choose the second-to-the-last picture at the end of the sequence (main task). At the same time, participants monitored and reported the gender of face images that occasionally appeared around the central picture (secondary task). The sum of the normalized scores of both tasks was used as an index of multitasking ability. We also measured participants’ attention distribution ability (face ensemble task; Cha et al., 2021) and face recognition ability (Cambridge Face Memory Test; Duchaine & Nakayama, 2006). We found a positive correlation between multitasking ability and attention distribution ability after controlling for face recognition ability. Whereas the correlation between multitasking ability and MUQ scores was close to zero. These results suggest that practical multitasking could involve distributing attention to the main and secondary tasks, and practical multitasking skills may not improve with experiences.