Prioritizing Working Memory Resources Depends on the Prefrontal Cortex

Area of Science:

• Neuroscience
• Cognitive Psychology

Background:

• The precise role of the prefrontal cortex in working memory is debated, with theories focusing on either memory storage or content control.
• Understanding this distinction is crucial for developing accurate models of cognitive function.

Purpose of the Study:

• To investigate whether the prefrontal cortex primarily stores working memory content or controls the allocation of cognitive resources.
• To differentiate between storage and control theories of prefrontal cortex function in working memory.

Main Methods:

• Utilized transcranial magnetic stimulation (TMS) to perturb the lateral prefrontal cortex in human participants (both sexes).
• Employed a working memory task requiring behavioral prioritization of memory items.
• Developed a computational model to predict the effects of control disruption.

Main Results:

• Disruption of the superior precentral sulcus via TMS led to improved memory for low-priority items, as predicted by the computational model.
• Perturbation of the intraparietal sulcus did not yield the same effect.
• Results suggest a causal role for the lateral prefrontal cortex in resource allocation.

Conclusions:

• The prefrontal cortex's primary role in working memory is the control of resource allocation, not the passive storage of information.
• Findings support computational models emphasizing the dynamic control of cognitive resources over static memory storage frameworks.