The concept of biased thinking - or cognitive biases - is relevant to psychotherapy research and clinical conceptualization, beyond cognitive theories. The present naturalistic study aimed to examine the changes in biased thinking over the course of a short-term dynamic psychotherapy (STDP) and to discover potential links between these changes and symptomatic improvement. This study focuses on 32 self-referred patients consulting for Adjustment Disorder according to DSM-IV-TR. The therapists were experienced psychodynamically oriented psychiatrists and psychotherapists. Coding of cognitive biases (using the Cognitive Errors Rating Scale; CERS) was made by external raters based on transcripts of interviews of psychotherapy; the reliability of these ratings on a randomly chosen 24% of all sessions was established. Based on the Symptom Check List SCL-90-R given before and after, the Reliable Change Index (RCI) was used. The assessment of cognitive errors was done at three time points: early (session 4-7), mid-treatment (session 12-17), and close to the end (after session 20) of the treatment. The results showed that the total frequency of cognitive biases was stable over time (p = .20), which was true both for positive and for negative cognitive biases. In exploring the three main subscales of the CERS, we found a decrease in selective abstraction (p = .02) and an increase in personalization (p = .05). A significant link between RCI scores (outcome) and frequency of positive cognitive biases was found, suggesting that biases towards the positive might have a protective function in psychotherapy.
Therapists may be attentive to changes in biased thinking across short-term dynamic psychotherapy for adjustment disorder. Therapists may foster the emergence of positive cognitive biases at mid-treatment for adjustment disorder.