Examining differences in cognitive and affective theory of mind between persons with high and low extent of somatic symptoms: an experimental study

BACKGROUND Medically unexplained somatic symptoms are common, associated with disability and strongly related to depression and anxiety disorders. One interesting, but to date rarely tested, hypothesis is that deficits in both theory of mind (ToM) and emotional awareness may undergird the phenomenon of somatization. This study sought to investigate whether or not differences in ToM functioning and self-reported emotional awareness are associated with somatic symptoms in a sample from the general population. METHODS The sample consisted of 50 healthy participants (37 females, 13 males) aged between 22 and 64 years (46.8 ± 11.7) of whom 29 reported a high extent of somatic symptoms (HSR), whereas 21 reported a low extent of somatic symptoms (LSR) based on the 30 highest and lowest percentiles of the Symptom List norms. The participants' affective and cognitive ToM were assessed with two experimental paradigms by experimenters who were blind to the participants' group membership. In addition, self-reports regarding emotional awareness, alexithymia, depressive and anxiety symptoms and current affect were collected. RESULTS In the experimental tasks, HSR showed lower affective ToM than LSR but the groups did not differ in cognitive ToM. Although HSR reported lower emotional awareness than LSR in the self-report measure, this group difference vanished when we controlled for anxiety and depression. Depression, anxiety, emotional awareness and alexithymia were correlated positively. CONCLUSIONS The data supported the hypothesis that deficits in affective ToM are related to somatic symptoms. Neither cognitive ToM nor self-reported emotional awareness were associated with somatic symptoms. Self-reported emotional awareness, alexithymia and symptoms of depression and anxiety shared a considerable amount of variance.