Schizophrenia

It has been argued that the formal thought disorder observed in schizophrenia strongly resembles spontaneous confabulation, in that it is often unprovoked and the content is frequently bizarre or fantastic.47 In fact, some authors have asserted that delusions and formal thought disorder may be indistinguishable from spontaneous confabulations except for the clinical context in which they arise.48,49 These observations have led to the investigation of confabulations in patients with schizophrenia. Although formal thought disorder is typically associated with spontaneous confabulations, most studies in patients with schizophrenia have focused on provoked confabulations, because these can be elicited in a structured setting.

In a study of provoked confabulations by Nathaniel-James and Frith,47 12 persons with schizophrenia and 12 controls were asked to recall 6 separate stories read aloud to them. A confabulation was defined as recall of information not present in the original narrative. Each person was also given a neuropsychological battery that included tests of memory and executive function. All of the schizophrenic participants confabulated to varying degrees, whereas only 1 control did so. Moreover, the authors found an association between the tendency to confabulate and the presence of formal thought disorder (eg, tangential thinking or loose associations). However, those with schizophrenia but without any formal thought process disorder also confabulated.

The authors concluded that the presence of thought disorder may contribute more to the severity of confabulations than to their presence in these patients. They also found an association between the number of confabulations in schizophrenic patients and an impaired ability to suppress inappropriate responses, as demonstrated by tests of executive functioning.

Not surprisingly—Simpson and Done50 found that delusions in those with schizophrenia also increased the frequency of confabulations, compared with nondeluded and nonpsychiatric controls.

In summary: formal thought disorder, the inability to suppress inappropriate responses, and the presence of delusions all appear to increase the likelihood or severity of confabulations in patients with schizophrenia.

CONCLUSION AND FUTURE DIRECTIONS

Confabulation is a significant clinical problem in many patients with neuropsychiatric disorders. As our opening clinical vignette suggests, a misunderstanding of confabulation can lead to inappropriate counter-transference on the part of clinical staff. We have also tried to show how confabulation may represent a “bridge” between psychiatry and neurology. Indeed, we believe that our understanding of several neuropsychiatric syndromes may be enhanced by our knowledge of confabulation.

To cite one example: Eack and coworkers51 have pointed to deficits in “foresight”—the ability to think of the long-term consequences of one’s behavior—in many patients with schizophrenia. These researchers have amassed MRI data that suggest foresight in patients with schizophrenia is related to the amount of gray matter in the right orbitofrontal and ventromedial prefrontal cortex. In particular, they hypothesize that reductions in gray matter volume in these regions may be associated with impaired foresight in schizophrenia. We have noted considerable (though not unequivocal) evidence that links damage to the orbitofrontal cortex with spontaneous confabulation.

We now ask: is there a link between impaired foresight and spontaneous confabulation in patients with schizophrenia? Futhermore, could any patient with damage to the orbitofrontal cortex—whether from stroke, demyelinating disease, or head trauma—be at increased risk for both impaired insight and confabulation? Now, both foresight and the accurate recollection of events require brain structures that can correctly assess and sequence past, present, and future. Could problems with such “temporal manipulation” be one thread that ties together schizophrenia and other conditions that involve orbitofrontal damage?

Answers to these questions must await further research but could have important implications for the cognitive rehabilitation of patients with various types of brain injury or disease.52 In short, we believe that confabulation is an excellent heuristic concept for building bridges between neurology and psychiatry.
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