Variation of temporal order reveals deficits in categorisation of facial expressions in patients afflicted with depression

ABSTRACTIntroduction: It is well established that depressive disorders are associated with abnormalities in the processing of affective information. However, type of stimuli, perceptual complexity and cognitive demand are important factors in evaluating these findings. In particular, processing mechanisms of perceptual boundaries in ecologically valid face stimuli are largely unknown in depression.Methods: In the current study, intensity-ordered frame sequences provided a dynamic visualisation of happy or sad facial expressions fading from or to neutral expressions. Patients (n = 20) with major depression (MD) disorder and controls (n = 20) indicated their perceptual boundaries between neutral and emotional face depending on direction and emotion. The averaged time of the perceptual boundary entered a group × condition ANOVA and regression analysis.Results: MD group did not systematically shift perceptual boundaries in the dynamic emotional faces but yielded altered statistics in information processing. T...