[Apathy in Parkinson's disease].

INTRODUCTION Apathy is a behavioural syndrome due to dysfunction of the process that gives rise to actions induced by external or personal stimuli. Apathy is very common in Parkinson's disease, with a prevalence that ranges between 16-48%. Three subtypes of apathy are currently accepted, which are anatomically and functionally different: cognitive, emotional and due to a deficit in auto-activation. Each of these subtypes is involved to a variable degree in the apathy of Parkinson's disease. The diagnosis is desupported by clinical, diagnostic and neuropsychological tests. The evaluation of the apathy must be done simultaneously along with with depression cognitive deficit. CONCLUSIONS Apathy has become a very important symptom to bear in mind in Parkinson's disease patients as it has significant repercussions on the quality of life of the patient. It is very important to do a differential diagnosis with the depression and the cognitive deficit since the therapeutic approach is different. Specific scales to measure this symptom should be included in the evaluation protocols of cognitive function in Parkinson's disease.