Abstract EN:

Several kinds of deficiencies have been characterized in Parkinson's Disease (PD). From the beginning of their illness, PD patients suffer from impairments in working memory and executive functions when handling information, in particular when experiencing new situations. Impairments in planning processes and strategy selection are observed in problem solving tasks. However, the cognitive processes which underlie those symptoms are still poorly identified. The aim of the present work is to characterize those cognitive processes from an analysis of verbal reports produced during the solving of the Tower of Hanoi - a test frequently used with this kind of patients. A comparative analysis is made of PD patients' verbal reports with those of control subjects, and with the participants' performance. For this purpose, reference is made to Culioli's theory of enunciative operations, these operations being cognitively interpreted as markers of cognitive processes, according to Caron-Pargue. Verbal reports were produced by 10 non-demented PD patients, and by 20 control subjects (10 matched Aged, and 10 Young). Their productions were compared, and put into relation with their performances, on the whole strategy, and also on each of the subgoals of the solving process. The problem was the 4-disk Tower of Hanoi, with disks of different sizes and colours, and 4 successive trials were made. Besides, the effect of verbalization was checked by comparing the performances with those of subjects who did not verbalize – namely 10 PD patients, 10 Aged and 10 Young, solving the same problem in 4 successive trials. Beyond a large common basis shared, in the learning process, by PD Patients and control subjects, the results allow to identify PD's deficiencies on particular points. Implicit learning, characterized from propositional contents, shows a contextualized construction, lending itself to a de-automatization as it advances…