Leistungserwartungen und neuropsychologische Defizite bei Menschen mit depressiven Störungen - Ein experimentelles Design zur Untersuchung des Zusammenhangs von induzierten Leistungserwartungen und der Leistungsperformanz in der neuropsychologischen Facette des verbalen Gedächtnisses

Background: Dysfunctional expectations have been highlighted as a core feature of depressive disorders. Findings from behavioral studies suggest that, in general, expectations can be modified by interventions and that these expectational modifications can influence cognitive and motor functions. Placebo- and anxiety- related research indicates that expectation-focused approaches could play a bigger role in depression therapy, for example by implementing expectation-focused psychological interventions. Yet, it has not been examined whether expectational modification could improve depressive patients’ cognitive ability, even though cognitive deficits such as verbal memory problems have been mentioned as relevant disorder-related disabilities. For this reason, an online experiment was developed in order to analyze if positive feedback could have a positive effect on situational expectations and if improved expectations could positively influence the subjects’ verbal memory test performance. Methods: People who were currently or formerly depressed (n = 76) were randomly assigned to an experimental condition (EG, n = 39), in which participants received positive performance related feedback, or to a control condition (CG, n = 37) which only offered neutral feedback. Performance related expectations and memory test performance in the German version of the Auditory Verbal Learning Test (Verbaler Merk- und Lernfähigkeitstest, VLMT) were measured before and after the intervention. Results: Our results suggest that subjects from the EG positively updated their performance related expectations after receiving positive feedback, whereas participants in the CG did not. However, improvement in situational expectations that was demonstrated in the EG did not have a positive effect on the test performance. Expectational improvement was rather associated with smaller increases in test performance in the EG. Conclusion: Our findings indicate that depressed people could be more accessible to positive feedback than previous work suggests. The prevalence of immunization strategies was not observed. Nevertheless, positive feedback did not seem to have the same positive impact on test performance as it has been demonstrated in healthy samples but rather seemed to thwart test performance in the depressed sample. Motivational and volitional deficits could account for these surprising findings. Further research is needed to explore the proposed mechanisms that could be involved. A better understanding of the links between feedback, expectations and cognitive performance could have important consequences regarding future treatment options of depressive disorders.