Frontopolar Cortex Interacts With Dorsolateral Prefrontal Cortex to Causally Guide Metacognition.

Area of Science:

• Cognitive Neuroscience
• Neuroimaging
• Brain Stimulation

Background:

• Metacognition, the ability to judge one's own cognitive performance, relies on understanding the quality and difficulty of mental processes.
• The precise neural mechanisms and brain regions involved in accurate metacognitive judgments remain largely unknown.
• The frontopolar cortex (FPC) is hypothesized to play a role in metacognition, potentially through interactions with other brain areas.

Purpose of the Study:

• To investigate the neural and psychological mechanisms underlying the frontopolar cortex's (FPC) role in metacognition.
• To test two-layer neural architectures of metacognition, where FPC communicates with regions encoding decision difficulty.
• To evaluate the contribution of self-directed mentalizing to metacognitive accuracy.

Main Methods:

• Combined high-intensity transcranial alternating current stimulation (tACS) over the FPC with functional neuroimaging.
• Administered 4 mA peak-to-peak tACS over the FPC during a metacognitive task.
• Analyzed neural coupling between FPC and dorsolateral prefrontal cortex (DLPFC) and assessed mentalizing performance.

Main Results:

• High-intensity tACS over the FPC significantly impaired metacognitive accuracy.
• Neural analysis revealed reduced FPC-DLPFC coupling during difficult metacognitive judgments following FPC tACS.
• FPC stimulation did not affect mentalizing performance, and metacognition and mentalizing networks showed only weak overlap.

Conclusions:

• The frontopolar cortex (FPC) is central to a two-layer architecture enabling accurate metacognitive judgments.
• FPC facilitates metacognition primarily through its connectivity with brain regions processing first-level task difficulty.
• Mentalizing processes contribute minimally to the FPC-mediated mechanisms of metacognitive accuracy.