title: A differential deficit in time- versus event-based prospective memory in Parkinson's disease.
abstract: 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.
  
  
  METHODS
  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.
authors.affiliation: Department of Psychology and Neuroscience Program, Trinity College, 300 Summit Street, Life Sciences Center 201, Hartford, CT 06106, USA. sarah.raskin@trincoll.edu
authors.forename: Sarah A
authors.initials: SA
authors.lastname: Raskin
authors.forename: Steven Paul
authors.initials: SP
authors.lastname: Woods
authors.forename: Amelia J
authors.initials: AJ
authors.lastname: Poquette
authors.forename: April B
authors.initials: AB
authors.lastname: McTaggart
authors.forename: Jim
authors.initials: J
authors.lastname: Sethna
authors.forename: Rebecca C
authors.initials: RC
authors.lastname: Williams
authors.forename: Alexander I
authors.initials: AI
authors.lastname: Tröster
mesh_terms: D000368:Aged; D000704:Analysis of Variance; D003072:Cognition Disorders / Q000209:etiology*; D056344:Executive Function / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D008569:Memory Disorders / Q000175:diagnosis / Q000209:etiology*; D008875:Middle Aged; D009483:Neuropsychological Tests; D010300:Parkinson Disease / Q000150:complications*; D021641:Recognition, Psychology / Q000502:physiology*; D013223:Statistics as Topic; D013997:Time Factors