Reduced positive emotion and underarousal are uniquely associated with subclinical depression symptoms: Evidence from psychophysiology, self-report, and symptom clusters.

Multiple models of aberrant emotional processing in depression have been advanced. However, it is unclear which of these models best applies to emotional disturbances in subclinical depressive symptoms. The current study employed a battery of psychophysiological measures and emotional ratings in a picture-viewing paradigm to examine whether the underarousal, low positive emotion, heightened negative emotion, or emotion context insensitivity model of emotional dysfunction in subclinical depressive symptoms received greatest support. Postauricular reflex and skin conductance response potentiation for pleasant minus neutral pictures (measuring low positive emotion), overall skin conductance magnitude and late positive potential (LPP) amplitude (measuring underarousal), and pleasant minus aversive valence ratings (measuring emotion context insensitivity) and aversive minus neutral arousal ratings (measuring heightened negative emotionality) were all negatively related to depressive symptomatology. Of these, postauricular reflex potentiation and overall LPP amplitude were incrementally associated with depressive symptoms over the other measures. Postauricular reflex potentiation, overall skin conductance magnitude, and aversive minus neutral arousal ratings were incrementally associated with depressive symptomatology after controlling for other symptoms of internalizing disorders. Though no model was unequivocally superior, the low positive emotion and underarousal models received the most support from physiological measures and symptom reports, with self-report data matching patterns consistent with the emotion context insensitivity model.