Cognitive Control & the Functional Organization of the Frontal Cortex
Brown University
Summary
The goal of this basic experimental clinical trial is to understand the effect of multitasking practice on the structure of neural representations of tasks in the human lateral prefrontal cortex and control brain regions. The main question it aims to answer is: What changes in neural representational structure predict improvements in multitasking behavior due to multitasking practice? Healthy human participants will learn two independent tasks, each mapping a set of stimuli to motor responses based on different rules. Participants will be randomized to one of two interventions. Participants assigned to the multitask practice intervention (MPI) will practice multitasking the two tasks over multiple days. Those assigned to the single-task practice intervention (SPI) will instead practice each task separately while controlling for the total number of practice opportunities associated with each task across the interventions. Both before and after the practice, the ability of all participants to perform both tasks simultaneously will be behaviorally measured using a well-established psychological refractory period (PRP) paradigm, and their neural representations will be measured using functional MRI while they perform the two tasks. Researchers will then compare improvements in multitasking behavior across the two groups, as well as changes in neural representational geometry of the tasks in the lateral prefrontal cortex and control brain regions, and test whether multitasking training is associated with specific changes in neural representations in the lateral prefrontal cortex.
Description
Background and Study Rationale: Human performance on a task deteriorates when it is performed concurrently with another task. This multitasking cost has been attributed to competition for shared computational or biological resources and there is considerable debate in the field about the specific nature of these putative resources. Extensive multitasking practice is known to reduce, and sometimes, abolish these costs. These practice-related gains have been attributed to changes in central processing, more efficient task scheduling, or the learning of specialized task representations. The huma…
Eligibility
- Age range
- 18–35 years
- Sex
- All
- Healthy volunteers
- Yes
Inclusion Criteria: * Normal or corrected to normal vision. Exclusion Criteria: * Left handedness * Presence or history of neurological or psychiatric disorders * Usage of brain related medications * Previous head injury and time spent unconscious * Any implanted medial fragment or device in the body of the participant. * Tattoos above the neck * Injury to the eye or other body part involving a metallic object or fragment. * Welding, grinding, or cutting of metal in lifetime of participant without usage of safety protection glasses. * injury to the participant by a metallic object or foreig…
Interventions
- BehavioralMultitask Practice Intervention (MPI)
Multitask practice intervention (MPI) includes multiple behavioral testing sessions during which participants receive practice with multitasking two tasks using the psychological refractory period procedure.
- BehavioralSingle-task Practice Intervention (SPI)
Single task practice intervention (SPI) includes multiple behavioral testing sessions during which participants receive separate practice on two tasks.
Location
- Metcalf Research Building, Brown University & MRI Research Facility, Brown UniversityProvidence, Rhode Island