Hedonic and behavioral deficits associated with apathy in Parkinson's disease: potential treatment implications.

BACKGROUND: Many individuals with Parkinson's disease (PD) experience apathy independent of depression. METHODS: In this study, we examined hedonic and behavioral deficits related to apathy in 50 patients with PD and 42 healthy older adults who completed standardized measures. RESULTS: Regression analyses revealed that apathy was associated with anticipatory, but not consummatory, anhedonia and reduced goal-directed behavior, independent of PD diagnosis, age, education, and depressive symptoms. CONCLUSIONS: These findings suggest that apathy is characterized by deficits in anticipatory pleasure and behavioral drive rather than consummatory pleasure or reward responsiveness. Therefore, PD patients with apathy would likely benefit from psychotherapeutic treatment that encourages structured, goal-directed plans for pleasurable events and stimulation that provide adaptive hedonic effects. In addition, given the proposed shared mechanism of dopamine depletion within the ventral striatum in apathy and anticipatory anhedonia, future trials of dopamine-eliciting activities (eg, exercise and other nonpharmacologic methods) appear to be warranted to improve these symptoms in patients with PD. © 2013 Movement Disorder Society.

Cognitive predictors of verbal memory in a mixed clinical pediatric sample.

Verbal memory problems, along with other cognitive difficulties, are common in children diagnosed with neurological and/or psychological disorders. Historically, these "memory problems" have been poorly characterized and often present with a heterogeneous pattern of performance across memory processes, even within a specific diagnostic group. The current study examined archival neuropsychological data from a large mixed clinical pediatric sample in order to understand whether functioning in other cognitive areas (i.e., verbal knowledge, attention, working memory, executive functioning) may explain some of the performance variability seen across verbal memory tasks of the Children's Memory Scale (CMS). Multivariate analyses revealed that among the cognitive functions examined, only verbal knowledge explained a significant amount of variance in overall verbal memory performance. Further univariate analyses examining the component processes of verbal memory indicated that verbal knowledge is specifically related to encoding, but not the retention or retrieval stages. Future research is needed to replicate these findings in other clinical samples, to examine whether verbal knowledge predicts performance on other verbal memory tasks and to explore whether these findings also hold true for visual memory tasks. Successful replication of the current study findings would indicate that interventions targeting verbal encoding deficits should include efforts to improve verbal knowledge.