B&C Tuesday Seminar “Can we change depressive beliefs ? The cognitive effects of ketamine in patients with treatment resistant depression”
4 April @ 12 h 15 min - 13 h 15 min
Abstract :Theories of depression propose that the disease is maintained by negative biases in information processing that give rise to a triad of strong and long-lasting negative beliefs about the future, oneself and the world. Moreover, a third of patients do not show symptom improvement following monoaminergic antidepressant treatment. This has led to the notion of treatment resistant depression (TRD), and has encouraged alternative treatment strategies such as subanaesthetic doses of ketamine. Ketamine has been shown to induce rapid clinical improvement of TRD within 24 hours after a single infusion. However, it is less well known how ketamine alters maladaptive cognitive schemas and automatic thoughts that are at the heart of TRD in many patients. In this talk I will present empirical results from combining behavioral testing with a pharmacological challenge and computational modeling. We found that a single ketamine infusion induced optimism biases in how patients updated their beliefs about the future, which were explained by an increased learning asymmetry from positive estimation errors. The emergence of optimistically biased belief updating further correlated to the clinical effects after one week of ketamine treatment. Moreover, I will present first results of testing early ketamine effects also on affective information processing. Taken together, this talk will provide preliminary evidence for the cognitive effects of ketamine action in TRD, which offer a useful perspective for the development of drug-augmented psychotherapy of TRD.