Can Non-Pharmacological Antidepressant Treatments Influence the Processing of Affective Information?

Depressive disorders are commonly associated with abnormalities in affective cognition. When processing information with emotional content, the depressed brain typically exhibits mood-congruent negative biases; that is, an abnormal preference for negative relative to positive information. In turn, recent psychopharmacological research has revealed that antidepressant drug treatments have the ability to push affective information processing more towards a preferential processing of positive information. These observations have led to the postulation of a cognitive neuropsychological model of antidepressant treatment action. This model suggests that negative biases play an important causal (rather than just epiphenomenal) role in the development of depressed mood and efficacious antidepressant interventions exert their clinical effects by acutely counterbalancing these cognitive abnormalities. In this chapter, we extend the focus to non-pharmacological treatments for depression and ask whether they too can influence affective cognition, and, if so, what these effects look like. We highlight recent studies investigating how cognitive behavioural therapy, electroconvulsive therapy, transcranial direct current stimulation, and environmental therapeutics impact on affective information processing in patients with depression. We show that, for each of these treatments, at least some evidence exists that suggests an influence on affective cognition and that in some cases the observed effects are directly in line with the cognitive neuropsychological model. However, as will become clear, the currently available evidence is rather sparse and, in many regards, incomplete. We therefore conclude that—similar to antidepressant drugs—non-pharmacological treatments can also influence affective information processing in patients with depression. However, whether these changes can counterbalance negative biases, and whether they are causally involved in the clinical effects of the different treatments, remains to be elucidated by future research.