Confabulation and multiple sclerosis: a rare association

Abstract

Background: Fantastic confabulation in the context of Multiple Sclerosis (MS) has not previously been reported in the literature. The association is of interest because clearly demonstrable brain pathology in MS together with other cognitive and behavioural correlates may further our understanding of the neural basis underlying confabulation. Methods: A single case report with magnetic resonance imaging of the brain and detailed neuropsychological evaluation. Results: Confabulation occurred together with disinhibited and stimulus bound behaviour. While the patient's physical and emotional state limited the range of psychometric tests administered, the results revealed an inability to maintain focused, regulated information processing. Although memory difficulties were present, they were not in the nature of a severe amnesic disorder. The patient appeared to have a broad fund of knowledge, but the associations binding the information together and putting it into context were loose. All three features of a triad of responses previously described in confabulating patients were present, namely an inability to withhold answers, to monitor one's own responses and provide verbal self corrections. MRI of the brain showed bilateral periventricular lesions and discrete frontal lesions with 53% of the total lesion volume distributed in frontal areas. Cortical atrophy, most marked in frontal regions also was conspicuous. Conclusions: Confabulation linked to frontal lobe involvement may occur as part of the changes in mentation found in MS. It is, however, rare and although associated with impaired memory, may be found in the absence of a severe amnesic disorder. This conclusion is discussed in the light of observations from the literature suggesting that frontal involvement is a prerequisite before fantastic confabulation occurs.