The Prefrontal-Hippocampal Comparator: Volition and Episodic Memory

Area of Science:

• Neuroscience
• Cognitive Psychology
• Computational Neuroscience

Background:

• The prefrontal-hippocampal comparator model proposes a mechanism for evaluating actions and their consequences.
• Understanding the neural basis of episodic memory and its relation to voluntary action is crucial.

Purpose of the Study:

• To review recent research supporting and refining the prefrontal-hippocampal comparator model.
• To elucidate the roles of the hippocampus, prefrontal cortex, and corollary discharge in episodic memory and action evaluation.

Main Methods:

• This is a review of existing research, synthesizing findings from various studies.
• The review focuses on experimental evidence related to hippocampal function, episodic memory, and prefrontal cortex activity.

Main Results:

• Hippocampal area CA1 functions as an associative match-mismatch comparator.
• Voluntary movement enhances episodic memory formation for goal-directed behaviors.
• Hippocampal theta power acts as a prediction error signal in memory tasks.
• The self-referential aspect of human episodic memory involves corollary discharge from the prefrontal cortex to the hippocampus.

Conclusions:

• The hippocampus, particularly CA1, plays a key role in comparing expected and actual outcomes via corollary discharge.
• Dysfunction in corollary discharge may underlie symptoms observed in schizophrenia.
• Further research is needed to fully resolve outstanding questions and advance the model.