ERP and Theta Activity Associated with Facial Emotion Memory

<p>Facial emotion recognition is an important component of daily functioning and is highly connected to the social element of human interaction. At present, it is not clear whether initial stimulus encoding or memory maintenance of the face promotes accurate facial emotion memory. The purpose of this study was to explore the mechanisms of facial affect memory. Specifically, we aimed to compare whether type of emotion, length of delay interval, or robustness of encoding the initial stimulus were associated with accurate facial emotion recognition and memory. A task of explicit emotion memory was given to 30 participants. A visual stimulus of a face expressing one of 6 emotions (Very Happy, Happy, Neutral, Sad, Fear, Anger) was presented for 200ms. After a delay of either 500ms, 1000ms, or 2000ms participants were presented with another facial stimulus (with a different identity than the first stimulus) displaying either a matched or mismatched emotional expression. Participants indicated whether or not the second emotion matched the first by pressing a button with their dominant hand. Electroencephalography (EEG) was recorded from 32 channels during the entire task. A repeated measures ANOVA was used to determine if there were significant within-subject differences in event-related potential (ERP) amplitudes based on Facial Emotion, Delay Condition, and Time Interval. Finally, regression analyses were used to test whether the relationship between ERP amplitude and Theta Power predict behavioral performance. P1 amplitudes at occipital electrode sites and N170 amplitudes at parietal sites differed by emotional expression. Increased P1 at occipital sites was the best predictor of correct matching of positive emotions whereas N170 amplitudes at parietal sites predicted correct identification of negative emotions. Correct matching of faces expressing Fear was predicted by ERPs and Theta Power more than any other emotion. Theta Power was greatest in shorter delay intervals and declined throughout all delay intervals, but was not associated with behavioral performance. Emotions influence how well stimuli are perceived and encoded. Increased robustness of encoding of emotional visual stimuli predicts correct identification of emotions more than emotion maintenance during the delay.</p>

Name thesis:degree_name

Doctor of Philosophy (PhD)

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

Psychology

Year

2017

Author dc:creator

• Herman, Shaina Roxanne

Contributors dc:contributor

• Brenner, Colleen A.
• Hartman, Richard E.
• Lee, Grace J.

• Clinical Psychology
• Psychology
• Social and Behavioral Sciences
• Emotions; Human information processing; Visual Perception; Memory;
• Facial Emotion Recognition; Social Interaction; Memory Maintenance; Facial affect memory; Event-related potential

Statement dc:rights

• This title appears here courtesy of the author, who has granted Loma Linda University a limited, non-exclusive right to make this publication available to the public. The author retains all other copyrights.

Language dc:language

English

Repository record dc:identifier

https://scholarsrepository.llu.edu/etd/472

OAI identifier oai:identifier

oai:scholarsrepository.llu.edu:etd-1473