Prioritizing working memory resources depends on prefrontal cortex.

Area of Science:

• Cognitive Neuroscience
• Neurobiology

Background:

• The precise role of the prefrontal cortex in working memory is debated, with theories focusing on memory storage versus content control.
• Understanding this distinction is crucial for advancing cognitive neuroscience and developing targeted interventions.

Purpose of the Study:

• To investigate whether the prefrontal cortex primarily stores working memories or controls their prioritization.
• To differentiate between memory storage and resource allocation models 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 on memory performance.

Main Results:

• TMS of the superior precentral sulcus, but not the intraparietal sulcus, disrupted resource prioritization.
• This disruption led to an counterintuitive improvement in memory for low-priority items, aligning with model predictions.
• Demonstrated a causal link between prefrontal cortex control and working memory resource allocation.

Conclusions:

• The prefrontal cortex actively controls the allocation of cognitive resources supporting working memory.
• Findings support models emphasizing prefrontal cortex's role in dynamic resource management over passive memory storage.
• Provides causal evidence for the resource allocation theory of prefrontal cortex function in working memory.