An Emotional Bias in Processing Facial Expressions: Similarities and Differences across Age

Parks for their insightful comments on earlier versions of this thesis. Finally, I extend my gratitude to Ron and Allison Hilimire and Laura Hilimire for supporting me in my academic endeavors. Page Figure 1: Illustration of the sequence of a trial. 17 Figure 2: Young adult ERPs elicited by faces at lateral electrode sites. 22 Figure 3: Young adult ERPs elicited by faces at midline electrode sites. 23 Figure 4: Older adult ERPs elicited by faces at lateral electrode sites. 24 Figure 5: Older adult ERPs elicited by faces at midline electrode sites. 25 Figure 6: Young adult ERPs to probes located centrally over the faces 32 at short SOA. Figure 7: Older adult ERPs to probes located centrally over the faces at 32 at the short SOA. Figure 8: Young adult P1/N1 differences to probes located centrally over 35 the faces at the short SOA. Asterisks denote significance at p < 0.05. Figure 9: Older adult P1/N1 differences to probes located centrally over 35 the faces at the short SOA. Asterisks denote significance at p < 0.05. Figure 10: Young adult ERPs to probes located peripherally above the 38 faces at the short SOA. Figure 11: Older adult ERPs to probes located peripherally above the 38 faces at the short SOA. Figure 12: Young adult P1/N1 differences to probes located peripherally 40 above the faces at the short SOA. Asterisks denote significance at p < 0.05. Figure 13: Reaction time and accuracy for young and older adults. 44 Asterisks denote significance at p < 0.05. Both, young and older adults had faster RTs to emotional faces. EOG Electrooculogram ms Milliseconds cm Centimeters ix SUMMARY Previous research indicates that young adults (aged 18-30) tend to exhibit a " negativity bias " such that they enhance processing of negative emotional stimuli compared to neutral stimuli. Because of age-differences in emotion regulatory goals, older adults (aged 60+) often exhibit enhanced processing for positive rather than for negative stimuli – a " positivity effect. " I examined age-related differences in processing emotional facial expressions using event-related potentials (ERPs) elicited by task-relevant emotional (i.e., angry, sad, happy) and neutral face images and concurrent task-irrelevant central and peripheral probes. The results indicate that young and older have similarities and differences in their processing of emotional expressions. Both groups exhibit enhanced processing of all emotional facial expressions. This suggests that there is neither a " negativity …