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Objective: The aim of the current study was to clarify the nature and extent of impairment in time- versus
event-based prospective memory in Parkinson’s disease (PD). Prospective memory is thought to involve
cognitive processes that are mediated by prefrontal systems and are executive in nature. Given that
individuals with PD frequently show executive dysfunction, it is important to determine whether these
individuals may have deficits in prospective memory that could impact daily functions, such as taking
medications. Although it has been reported that individuals with PD evidence impairment in prospective
memory, it is still unclear whether they show a greater deficit for time- versus event-based cues. Method:
Fifty-four individuals with PD and 34 demographically similar healthy adults were administered a
standardized measure of prospective memory that allows for a direct comparison of time-based and
event-based cues. In addition, participants were administered a series of standardized measures of
retrospective memory and executive functions. Results: Individuals with PD demonstrated impaired
prospective memory performance compared to the healthy adults, with a greater impairment demonstrated
for the time-based tasks. Time-based prospective memory performance was moderately correlated
with measures of executive functioning, but only the Stroop Neuropsychological Screening Test emerged
as a unique predictor in a linear regression. Conclusions: Findings are interpreted within the context of
McDaniel and Einstein’s (2000) multiprocess theory to suggest that individuals with PD experience
particular difficulty executing a future intention when the cue to execute the prescribed intention requires
higher levels of executive control.


This article may not exactly replicate the final version published in the APA journal. It is not the copy of record.