Impact of negative emotion on the neural correlates of long-term recognition in younger and older adults

Frontiers in Integrative Neuroscience

Anna eRieckmann¹  Lars eBäckman¹  Grégoria eKalpouzos¹  Håkan eFischer²  Stuart W.S. MacDonald³ 

[1] Karolinska Institute - Stockholm University;University of Stockholm;University of Victoria;

关键词: Aging;    Amygdala;    Hippocampus;    Prefrontal Cortex;    emotion;    episodic memory;   

DOI  :  10.3389/fnint.2012.00074

来源: DOAJ

【 摘 要 】

Some studies have suggested that the memory advantage for negative emotional information over neutral information (negativity effect) is reduced in aging. Besides the fact that most findings are based on immediate retrieval, the neural underpinnings of long-term emotional memory in aging have so far not been investigated. To address these issues, we assessed recognition of neutral and negative scenes after one- and 3-week retention intervals in younger and older adults using fMRI. We further used an event-related design in order to disentangle successful, false and true recognition. This study revealed 4 key findings: 1) Increased retention interval induced an increased rate of false recognitions for negative scenes, cancelling out the negativity effect (present for hit rates only) on discrimination in both younger and older adults; 2) In younger, but not older, adults, reduced activity of the medial temporal lobe was observed over time for neutral scenes, but not for negative scenes, where stable or increased activity was seen; 3) Engagement of amygdala was observed in older adults after a 3-week delay during successful recognition of negative scenes (hits versus misses) in comparison with neutral scenes, which may indicate engagement of automatic processes, but engagement of ventrolateral prefrontal cortex was unrelated to amygdala activity and performance; and 4) After 3 weeks, but not after one week, true recognition of negative scenes was characterized by more activity in left hippocampus and lateral occipito-temporal regions (hits versus false alarms). As these regions are known to be related to consolidation mechanisms, the observed pattern may indicate the presence of delayed consolidation of true memories. Nonetheless, older adults’ low performance in discrimination of negative scenes could reflect the fact that overall, after long delays of retention, they rely more on general information rather than on perceptual detail in making recognition judgments.

【 授权许可】

Unknown