Self-reported cognition in Exhaustion Disorder: From brain to experience

Exhaustion disorder (ED) is a relatively new diagnosis associated with cognitive symptoms, which are normally assessed using standardized cognitive tests or questionnaires targeting everyday cognitive failures (i.e., subjective cognitive complaints, SCCs). The purpose of this thesis was to add empirical knowledge on the self-reported, first-hand experience of cognitive function in ED. More specifically, it aimed to learn how SCCs relate to test performance, psychological distress and neural activity. Further objectives were to evaluate the types of difficulties being expressed, and what aspects can be considered helpful or hindering with respect to cognitive recovery. Study 1 found that when compared to healthy controls, ED patients reported substantially higher levels of SCCs, and were more likely to express difficulties in situations without external memory cues. In both groups, the level of SCCs was correlated with psychological distress and not with cognitive test-results. Using functional magnetic resonance imaging, Study 2 investigated the relationship between SCCs, test performance and brain activity. There was no association between SCCs and behavioural results on the in-scanner task, tapping response inhibition. However, a positive correlation was detected between SCCs and relatively more brain activity in a cluster in the right-side occipital lobe during the more difficult task condition. This exploratory finding may indicate compensational neural activity, possibly involving visual processing or the altering between task positive and task negative neural networks. Study 3 analysed interviews with people who had participated in ED-rehabilitation 6-10 years earlier, and displayed a range of individual experiences. Cognitive symptoms had been highly distressing. Lingering problems were also noted in several cognitive areas, but maintenance of attention and executive control may be domain-general areas of importance. Cognitive recovery was seen as closely tied to context, including the overall life situation and general recovery from ED, which varied between individuals. Hence, different restorative or compensatory strategies were considered helpful, as were optimization of the external environment and a change in approach towards the own self and cognitive performance. In sum, this thesis studied the subjectively reported cognitive symptoms in ED. It has supported and extended previous findings by showing how substantial cognitive difficulties may be experienced, and that the expression of these problems is intricately linked to different facets and levels of cognition.