Summary: Study reports the putamen, not just the cortex, contributes to the brain’s ability to multitask.
Source: SfN
Multitasking performance stems from the speed of information exchange between inner and outer regions of the brain, according to new research in eNeuro.
Doing two things at once courts disaster, as multitasking requires outer cortical brain regions to rapidly communicate with each other. The speed of this information exchange limits multitasking capability yet can improve with practice. But that’s not the whole story: multitasking also depends on the striatum, a previously overlooked region deep inside the brain.
Garner et al. compared the brain activity of 100 healthy adults before and after a week of multitasking practice. The participants completed two different tasks, first separately and then at the same time. The putamen — a brain region in the striatum involved in habitual behavior — and two cortical regions were activated by the tasks separately and increased activity during multitasking.
After testing a variety of potential models, the research team found that multitasking ability hinged on how effectively the putamen could exchange information with the cortical areas. A week of practice improved the participant’s task performance in concert with an increase in communication rates between the putamen and the cortex.
About this neuroscience research article
Source:
SfN
Contacts:
Calli McMurray – SfN
Image Source:
The image is credited to Garner et al., eNeuro 2020.
Original Research: Closed access
“Cognitive Capacity Limits Are Remediated by Practice-Induced Plasticity Between the Putamen and Pre-Supplementary Motor Area” by K.G. Garner, M.I. Garrido and P.E. Dux. eNeuro.
Abstract
Cognitive Capacity Limits Are Remediated by Practice-Induced Plasticity Between the Putamen and Pre-Supplementary Motor Area
Humans show striking limitations in information processing when multitasking, yet can modify these limits with practice. Such limitations have been linked to a frontal-parietal network, but recent models of decision-making implicate a striatal-cortical network. We adjudicated these accounts by investigating the circuitry underpinning multitasking in 100 human individuals and the plasticity caused by practice. We observed that multitasking costs, and their practice induced remediation, are best explained by modulations in information transfer between the striatum and the cortical areas that represent stimulus-response mappings. Specifically, our results support the view that multitasking stems at least in part from taxation in information sharing between the putamen and pre-supplementary motor area (pre-SMA). Moreover, we propose that modulations to information transfer between these two regions leads to practice-induced improvements in multitasking.
Significance statement
Humans show striking limitations in information processing when multitasking, yet can modify these limits with practice. Such limitations have been linked to a frontal-parietal network, but recent models of decision-making implicate a striatal-cortical network. We adjudicated these accounts by investigating the circuitry underpinning multitasking in 100 individuals and the plasticity caused by practice. Our results support the view that multitasking stems at least in part from taxation in information sharing between the putamen and pre-supplementary motor area (pre-SMA). We therefore show that models of cognitive capacity limits must consider how subcortical and cortical structures interface to produce cognitive behaviours, and we propose a novel neurophysiological substrate of multitasking limitations.
