Negative affect interacts with perceptual affective biases.

BACKGROUND: Affective biases are central to mood and anxiety disorders, with individuals often interpreting ambiguous facial expressions more negatively. Adaptation paradigms, where exposure to emotional stimuli shifts perception, provide a tool to separate perceptual from decisional biases, but have not been used to study emotional biases relevant to affective disorders.

AIMS: To determine whether affective biases in facial emotion perception arise from perceptual or decisional processes, and to examine how these biases are modulated by individual differences in negative affect.

METHODS: Eighty participants completed emotion and identity discrimination tasks before and after adaptation. Participants made binary judgements of morphed facial expressions (happy/sad) and identities (Bonny/Sheila), followed by confidence ratings. Logistic and Gaussian functions were used to estimate adaptation effects from shifts in the point of subjective equality (PSE) and peak uncertainty.

RESULTS/OUTCOMES: Adaptation produced repulsive aftereffects: exposure to happy faces biased perception towards sadness, and vice versa, with analogous effects for identity. Correlated shifts in PSE and uncertainty indicated a perceptual rather than decisional origin. Negative affect (derived from Beck Depression Inventory and State Trait Anxiety Inventory-trait questionnaires) moderated this relationship, such that individuals higher in negative affect showed stronger perceptual biases towards sadness.

CONCLUSIONS/INTERPRETATION: Findings suggest that negative affect modulates low-level perceptual encoding of emotional expressions. This supports cognitive neuropsychological models positing that antidepressants first target early perceptual biases and highlight perceptual encoding as a potential mechanism underlying affective biases in mood and anxiety disorders.