Goal- and retrieval-dependent activity in the striatum during memory recognition

Area of Science:

• Neuroscience
• Cognitive Psychology

Background:

• The striatum's role in successful memory retrieval is established, but its precise function remains debated.
• Current hypotheses suggest striatal activity may reflect outcome evaluation based on behavioral goals, rather than direct memory reactivation.

Purpose of the Study:

• To investigate if striatal activity during memory recognition correlates with subjective value.
• To differentiate between striatal responses related to confidence/subjective value and those related to perceived memory oldness.

Main Methods:

• Functional magnetic resonance imaging (fMRI) was employed during a recognition memory task.
• Participants rated both recognition confidence and the pleasantness of retrieved memories.
• Behavioral and brain activation data were analyzed for correlations.

Main Results:

• A strong positive correlation was observed between memory confidence and pleasantness, both behaviorally and in striatal activation.
• Experienced pleasantness explained most of the variance in the striatal confidence signal.
• Striatal activation related to perceived oldness was distinct from that associated with confidence and pleasantness.

Conclusions:

• Striatal activation during recognition memory involves at least two independent processes.
• One process reflects a flexible evaluation dependent on context and goals (memory confidence/pleasantness).
• Another process may be related to memory retrieval itself (perceived oldness).