Abstract
Cognitive alexithymia is associated with impairments in identifying, verbalizing, and analyzing (particularly negative) emotions, which may be rooted in atypical hemispheric laterality and/or stimulus properties. We investigated how alexithymic traits affected processing of emotional scenes using a laterality task in which participants judged the pleasantness of 120 images presented in the presence or absence of a peripheral distractor. Half of the scenes depicted implied motion. Right-handed adults (N = 106) were classified as exhibiting low, moderate, or high levels of cognitive alexithymia using scores from the Toronto Alexithymia Scale – 20 (Parker et al., 2003). Contrary to expectations, no laterality effects were observed. Participants made correct judgments more quickly when a peripheral distractor was presented with the scene, F(2, 103) = 90.43, p < .001, ηp2 = .468. Participants were also slower at correctly judging negatively valenced scenes, F(1, 103) = 6.50, p = .012, ηp2 = .059, and those that contained implied motion, F(1, 103) = 6.04, p = .016, ηp2 = .055, suggesting that these scenes were difficult to process. Accuracy was higher for positive scenes with no implied motion than for other types of scenes, F(1, 103) = 32.93, p < .001, ηp2 = .242. Finally, participants with low levels of alexithymia showed better accuracy for positive scenes but no effect of implied motion, whereas those with moderate-to-high alexithymia showed the opposite pattern [Group X Motion: F(2, 103) = 4.03, p = .02, ηp2 = .073; Group X Valence: F(2, 103) = 3.03, p = .05, ηp2 = .056]. Overall, our results show that stimulus properties, such as implied motion and valence, influence how effectively people with varying levels of cognitive alexithymia process emotional information. These findings provide new insights into the nature of alexithymic deficits and into the functioning of the social brain more generally.
Meeting abstract presented at VSS 2018