Age differences in medial prefrontal activity for subsequent memory of truth value

Area of Science:

• Neuroscience
• Cognitive Psychology
• Gerontology

Background:

• Aging is associated with declines in source memory, but socioemotional content can mitigate these differences.
• Dorsomedial prefrontal cortex (dmPFC) and ventromedial prefrontal cortex (vmPFC) activity are implicated in source memory, with differential recruitment potentially linked to personal relevance.
• Perceived truth value of information may influence attention and personal connection, impacting memory encoding.

Purpose of the Study:

• To investigate how the perceived truth value of information affects prefrontal cortex (PFC) activity during source memory encoding across age groups.
• To explore age-related differences in neural recruitment within the PFC during memory encoding of true versus false statements.

Main Methods:

• Twelve young adults (18-23 years) and 12 older adults (63-80 years) participated.
• Participants encoded true and false statements.
• Brain activity associated with subsequent memory was measured using functional neuroimaging.

Main Results:

• Behavioral memory performance was comparable between young and older adults.
• Young adults showed greater dmPFC activity, while older adults exhibited enhanced vmPFC and insula engagement.
• Neural activity differences suggest young adults may prioritize general knowledge, while older adults focus on emotional relevance.

Conclusions:

• Age-related differences in PFC recruitment during source memory encoding can underlie age-equivalent behavioral performance.
• Older adults' engagement of vmPFC and insula may reflect a focus on the emotional salience of information.
• Findings highlight distinct neural strategies for memory encoding that maintain behavioral function across the lifespan.