Recognition memory span in autopsy-confirmed Dementia with Lewy Bodies and Alzheimer's Disease.

Evidence from patients with amnesia suggests that recognition memory span tasks engage both long-term memory (i.e., secondary memory) processes mediated by the diencephalic-medial temporal lobe memory system and working memory processes mediated by fronto-striatal systems. Thus, the recognition memory span task may be particularly effective for detecting memory deficits in disorders that disrupt both memory systems. The presence of unique pathology in fronto-striatal circuits in Dementia with Lewy Bodies (DLB) compared to AD suggests that performance on the recognition memory span task might be differentially affected in the two disorders even though they have quantitatively similar deficits in secondary memory. In the present study, patients with autopsy-confirmed DLB or AD, and Normal Control (NC) participants, were tested on separate recognition memory span tasks that required them to retain increasing amounts of verbal, spatial, or visual object (i.e., faces) information across trials. Results showed that recognition memory spans for verbal and spatial stimuli, but not face stimuli, were lower in patients with DLB than in those with AD, and more impaired relative to NC performance. This was despite similar deficits in the two patient groups on independent measures of secondary memory such as the total number of words recalled from long-term storage on the Buschke Selective Reminding Test. The disproportionate vulnerability of recognition memory span task performance in DLB compared to AD may be due to greater fronto-striatal involvement in DLB and a corresponding decrement in cooperative interaction between working memory and secondary memory processes. Assessment of recognition memory span may contribute to the ability to distinguish between DLB and AD relatively early in the course of disease.

Predictors of discrepancies in Parkinson's disease patient and caregiver ratings of apathy, disinhibition, and executive dysfunction before and after diagnosis.

Parkinson's disease (PD) patient and caregiver reports of patient functioning are often used interchangeably in clinical and research settings; however, the consistency of these reports is largely unknown. This study aimed to investigate the consistency and predictors of discrepancy between self- and caregiver reports of patient apathy, disinhibition, and executive dysfunction. Fifty-one pairs of nondemented PD patients and their caregivers completed the frontal systems behavior scale (FrSBe). Patients were administered a neuropsychological battery, and mood and burden were assessed in a subset of caregivers. Patients and caregivers significantly differed in their ratings of all retrospective prediagnosis behaviors and current levels of disinhibition. Current levodopa equivalent dosages predicted patient-caregiver rating differences in prediagnosis and current apathy and current executive dysfunction, while patient motor function, cognition, and mood failed to predict any disparities in ratings. Caregiver burden and depression were associated with apathy rating discrepancies, while burden was associated with discrepancies in ratings of disinhibition. These results suggest that consistency of patient and caregiver behavioral ratings may vary depending on the behavior assessed; and underscore the importance of considering the reporter when using subjective measures, as discrepancies in behavioral reports may be influenced by specific patient and/or caregiver symptoms or factors.

Prospective memory deficits are associated with poorer everyday functioning in Parkinson's disease.

Although individuals with Parkinson's disease (PD) evidence moderate deficits in prospective memory (PM), it is not known whether PM deficits confer an increased risk of poorer everyday functioning. In the current study, 33 individuals with PD and 26 demographically similar normal controls (NC) were administered performance-based and self-report measures of PM and everyday functioning, including medication and financial management. As compared to NC, PD participants demonstrated significantly lower scores on performance-based measures of PM and financial capacity, worse performance at a trend level on performance-based medication management and endorsed significantly greater self-reported declines in PM and instrumental activities of daily living (iADLs). In the PD sample, the laboratory measure of PM significantly correlated with performance-based measures of financial capacity and medication management and a self-report measure of medication management. Self-reported PM failures significantly correlated with perceived declines in iADLs, worse medication management, and poorer health-related quality of life. Although future studies are needed to examine the incremental ecological validity of PM in PD, findings from this study extend prior research by providing preliminary evidence that PM impairment may play a significant role in a range of critical everyday functions in PD.