Maratos, Elizabeth Jayne; (2001) Episodic memory for emotional information: Event-related potential and functional magnetic resonance imaging studies. Doctoral thesis (Ph.D.), University College London (United Kingdom).

Preview

Text Episodic_memory_for_emotional_.pdf Download (13MB) | Preview

Abstract

The neural correlates of emotional episodic memory are investigated in a series of neuroimaging experiments (ERP, fMRI) through the comparison of memory effects elicited during retrieval of emotional relative to neutral information. In the first two ERP studies, it is revealed that emotionally-valenced words influence recognition memory primarily by virtue of their high levels of 'semantic-cohesiveness'. Furthermore, the findings reveal that the arrangement of emotional and neutral retrieval cues at test (blocked versus intermixed) influences processing carried out upon retrieved emotional episodic information. The findings across the third and fourth ERP studies indicate that incidental retrieval of emotional context (encoding environment) gives rise to greater activity in neural systems supporting episodic retrieval than does retrieval of non-emotional context. When context retrieval is intentional, by contrast, emotional and non-emotional episodic memory are associated with equivalent levels of engagement. The findings of the fourth ERP study are consistent with the existence of additional neural circuitry that is activated selectively by emotionally toned episodic information. In a final event-related fMRI study it is revealed that the retrieval of emotionally negative relative to emotionally neutral context elicits enhanced activity in brain regions including prefrontal cortex, amygdala, hippocampus and retrosplenial cortex. Recognition of words from positive relative to neutral contexts is associated with increased activity in prefrontal and orbitofrontal cortex, and in the left anterior temporal lobe. The fMRI findings provide further support for the proposal that the incidental retrieval of emotional information enhances activity in networks supporting episodic retrieval of neutral information. In addition, the fMRI findings suggest that regions known to be activated when emotional information is encountered in the environment are also active when emotional information is retrieved from memory. Whilst the findings are noteworthy in their own right, they also have implications for future studies of emotional memory. It is proposed that the employment of paradigms which involve the retrieval of emotional context through presentation of non-emotional retrieval cues may offer advantages over paradigms wherein the retrieval cues themselves are emotional.

Download activity - last month

Export as JSONCSVXML

Download activity - last 12 months

Export as XMLCSVJSON

Downloads by country - last 12 months

Export as CSVXMLJSON

Archive Staff Only

View Item