Declarative memory in early Parkinson's disease: Serial position learning effects

This study tested the question of whether executive failure associated with frontal lobe deficit is associated with, and therefore, may influence decl arative memory dysfunction in Parkinson's disease (PD). A variety of memory and 'frontal sensitive' tasks were used. The 'frontal lobe dysfunction' hy pothesis was tested in part, by examining the serial position effects (SPE) of word list learning across five successive trials. The relationship betw een memory and 'frontal sensitive' task scores was tested also. A total of 39 PD patients early in the course of the disease and 31 matched controls w ere included in the study. The PD subjects showed mild memory deficits in c omparison to the healthy control group. In the face of any hypothesized sel ective 'dysexecutive' syndrome in PD group, the latter groups learning stra tegy across five trials did not differ from that of the control group. Also , the expected interrelation between memory and 'frontal sensitive' scores was not obtained. Therefore, the hypothesis that frontal dysfunction alone may account for memory impairments in PD is not fully supported.