Introduction

Dementia is a syndrome which involves progressive disturbance of multiple cognitivefunctions, emotional control and social behaviour in clear consciousness (InternationalClassification of Diseases, ICD-10).1 Alzheimer’s disease (AD)accounts for more than 50% of all dementias and hence is the most widelystudied. Although Alzheimer’s first description of the condition includednoncognitive features like hallucinations, delusions and screaming,2 mostresearch has focused on the cognitive features, i.e. memory loss, perceptuo-motorskills and language disturbance.