Theory of Mind in Bipolar Disorder, with Comparison to the Impairments Observed in Schizophrenia

Abstract

Our ability to make sense of information on the potential intentions and dispositions of others is of paramount importance for understanding their communicative intent, and for judging what an appropriate reaction might be. Thus, anything that impinges on this ability has the potential to cause significant social impairment, and compromise an individual’s level of functioning. Both bipolar disorder and schizophrenia are known to feature theory of mind impairment. We conducted a theoretical review to determine the extent and types of theory of mind impairment in bipolar disorder, and evaluate their relationship to medication and symptoms. We also considered possible mediatory mechanisms, and set out to discover what else could be learnt about the impairment in bipolar disorder by comparison to the profile of impairment in schizophrenia. The literature established that in bipolar disorder (i) some form of theory of mind impairment has been observed in all mood states, including euthymia, (ii) the form of theory of mind assessed and task used to make the assessment influence the impairment observed, and (iii) there might be some relationship to cognitive impairment, although a relationship to standard clinical variables was harder to establish. What also became clear in the literature on bipolar disorder itself was the possible relationship of theory of mind impairment to history of psychotic symptoms. Direct comparative studies, including patients with schizophrenia, were thus examined, and provided several important directions for future research on the bases of impairment in bipolar disorder. Particularly prominent was the issue of whether theory of mind impairment could be considered a candidate endophenotype for the psychoses, although current evidence suggests that this may be premature. The differences in impairment across schizophrenia and bipolar disorder may, however, have genuine differential effects on social functioning and the likely success of remediation.

The metabolic basis of psychosis in bipolar disorder: A positron emission tomography study

“…Moreover, in our study we also found that BD patients had FDG uptake alterations in middle and inferior temporal cortex, regions found to be widely involved in the pathogenesis of mood disorders . This is not surprising especially because the temporal lobe is associated with several cognitive functions, such as language processing and Theory of Mind, that are often described impaired in BD patients . Moreover, the temporal cortex is functionally connected to the amygdala and prefrontal cortex and it seems to have a role in detection and representation of emotions, along with occipital cortex .…”

“…28 This is not surprising especially because the temporal lobe is associated with several cognitive functions, such as language processing and Theory of Mind, 29 that are often described impaired in BD patients. 30 Moreover, the temporal cortex is functionally connected to the amygdala and prefrontal cortex and it seems to have a role in detection and representation of emotions, along with occipital cortex. 17 Our results seem therefore in line with previous studies, showing a GM shrinkage 28 and an altered metabolic function 16,31 in temporal areas in BD patients.…”

Theory of mind impairment and its clinical correlates in patients with schizophrenia, major depressive disorder and bipolar disorder

“…However, there are still some other studies which found significant relationships between ToM impairment with clinical symptoms and general cognitive functions (Bora et al, 2016a;Bora et al, 2009b). Mitchell and Young (2015) think that the relationship between ToM impairments with positive psychotic symptoms may not be disease-specific, but symptom-specific. Marjoram et al (2005) examined ToM abilities in patients with SCZ and affective disorders and found that hallucinations and delusions were associated with ToM impairment, regardless of diagnosis.…”

Genetic contribution to ‘theory of mind’ in adolescence

“…Similarly, a meta-analysis identified significant impairments in tasks involving theory of mind in individuals with schizophrenia 16 . Difficulties in theory of mind have also been identified in people with unipolar and bipolar disorders [17][18][19] , eating disorders 20 , and attention deficit and hyperactivity disorder or ADHD 21 . For example, a recent meta-analysis of theory of mind in people with eating disorders (15 studies, 677 cases and 514 controls) identified significant deficits in theory of mind in individuals with anorexia compared to typical controls 22 .…”