What's Happening in the Brain
As common as repetitive behaviour is in Alzheimer's disease , it has been the focus of comparatively little research. It arises as a consequence of not just memory impairment, but also due to problems in attention, executive dysfunction and mood. In our experience, the response to treatment varies, so that the extent to which it reflects a reversible effect of the lack of the brain chemical acetylcholine is not clear. The basis of repetitive behaviours has recently been described in an Irish study by Cullen B et al., Repetitive behaviour in Alzheimer's disease: description, correlates and functions. Int J Geriatr Psychiatry. 2005;20:686-93, and work from Cambridge suggests that it reflects damage to particular parts of the frontal lobes and related deep brain structures. Nyatsanza S, et al., A study of stereotypic behaviours in Alzheimer's disease and frontal and temporal variant frontotemporal dementia . J Neurol Neurosurg Psychiatry. 2003;74:1398-402. . It has been described as being successfully treated in nursing home residents with the drug risperidone. (Rabinowitz et al., Behavioral and psychological symptoms in patients with dementia as a target for pharmacotherapy with risperidone. J Clin Psychiatry. 2004 Oct;65(10):1329-34.