Neural Mechanisms Supporting the Relationship between Working Memory Capacity and Proactive Control

Area of Science:

• Cognitive Neuroscience
• Neuroimaging
• Individual Differences

Background:

• Prior research suggests a link between working memory capacity (WMC) and proactive control.
• The neural underpinnings of this relationship remain unclear.
• The Dual Mechanisms of Cognitive Control (DMCC) project provides a suitable dataset for investigation.

Purpose of the Study:

• To investigate the neural mechanisms underlying the relationship between WMC and proactive control.
• To identify specific brain regions and circuits involved in translating cognitive goals into action preparation.
• To explore the potential for cognitive enhancement targeting these neural pathways.

Main Methods:

• Utilized fMRI data from the DMCC project (N > 100) with tasks assessing proactive and reactive control.
• Behavioral analyses using the AX-CPT paradigm to measure target preparation (A-cue Bias index).
• fMRI analyses linked behavioral measures to neural activity in specific brain regions (rDLPFC, lMOT) and employed latent path analysis.

Main Results:

• Behavioral findings replicated prior work, showing A-cue Bias increased with proactive control and correlated with WMC.
• fMRI data revealed A-cue Bias was linked to increased activity in the left motor cortex (lMOT).
• WMC correlated with increased right dorsolateral prefrontal cortex (rDLPFC) activity, and latent path analysis supported the rDLPFC-lMOT circuit's role in mediating the WMC-A-cue Bias relationship.

Conclusions:

• The rDLPFC-lMOT neural circuit preferentially mediates the relationship between WMC and proactive control.
• This circuit translates strategic task goals into response preparation, a key mechanism of proactive control.
• Individual differences in this circuit suggest potential for cognitive enhancement strategies.