RESUMO
INTRODUCTION: Executive dysfunction is regularly reported in patients with Alzheimer's disease. Nevertheless few studies have focused on planning ability in this neurodegenerative disease. OBJECTIVES: This study aimed to investigate the formulation and the execution of plans in Alzheimer's disease using an ecological planning subtask derived from the Behavioural Assessment of the Dysexecutive Syndrome test battery, the "Zoo Map Test". There are two trials. The first trial consists of a "high demand" version of the subtask in which the subjects must plan in advance the order in which they will visit designated locations in a zoo (formulation level). In the second, or "low demand" version, the subject is simply required to follow a concrete externally imposed strategy to reach the locations to visit (execution level). The test was given to 16 patients with Alzheimer's disease and 13 normal elderly subjects. RESULTS: The two way ANOVAs mainly showed more difficulties in patients with Alzheimer's disease than in healthy elderly in both conditions. The difference between formulation and execution was greater in patients with Alzheimer's disease than in healthy elderly. Planning impairments mainly correlated with behavioural changes (in particular motivational changes) observed by patient's relatives. CONCLUSION: These results suggest that patients with Alzheimer's disease have some problems to mentally develop logical strategies and to execute complex predetermined plans, which are partially related to behavioural changes.
