Prefrontal working memory activity predicts episodic memory performance: A neuroimaging study.

Working memory (WM) and long term memory (LTM) are different neuropsychological processes, although distinction between these domains is an area of debate. LTM is thought to rely on hippocampal circuitry. Cognitive neuroscience models imply that WM processing may at least partially support LTM within regions of the prefrontal cortex (PFC). We sought to determine the association between PFC based WM processing and LTM in the visuospatial domain. In contrast to prior work, we aimed to query if WM was involved in learning and free recall trials as measured by standard neuropsychological tests of LTM. Forty-three older adults (24 with a diagnosis of amnestic Mild Cognitive Impairment and 19 elderly controls) were included in the analysis. Patients completed a fMRI task of visuospatial maintenance WM in which they were required to match a previously studied complex shape with one of two probes. Extent of activity in the right PFC during the WM task was tabulated for each patient. Hippocampal volume was quantified from T1 scans. On a separate day patients completed neuropsychological testing, including the Brief Visuospatial Memory Test- Revised (BVMT-R), which includes learning trials (total recall), delayed free recall, and recognition. Right PFC activity was associated with performance on BVMT-R total recall and delayed recall. Results from multiple regression showed that PFC activity explained an additional 9 % of the variance in memory performance above right hippocampal volume. These findings suggest that PFC processing that supports WM (including stimuli maintenance, retrieval, and selection) are also involved in LTM learning and recall.

Telemedicine and the evaluation of cognitive impairment: the additive value of neuropsychological assessment.

INTRODUCTION: The number of people in the United States living with dementia is projected to rise to over 7.1 million in the next 12 years, representing a 40% increase from current levels. This anticipated "dementia tsunami" has led to a recent state and national policy emphasis on early detection, improved care quality, reduced caregiver burden, and increased access to care. The ability to achieve these objectives is limited by few dementia specialists in rural and small communities and the challenges of travel to and within congested urban regions for dementia patients and their caregivers. Telemedicine is one such means for responding to this lack of access to subspecialty assessment and care. We describe our early experiences with this technology applied to neuropsychological assessments, with data from 31 patients. METHODS: As part of an interdisciplinary dementia care demonstration project, clinical video teleconferencing provides real-time high resolution video interactions between dementia subspecialists in a major metropolitan medical center and patients in 3 outlying clinics located 180, 150, and 100 miles away. Comprehensive neuropsychological assessments, designed to address referral questions related to neurocognitive disorders via clinical video teleconferencing, are conducted as one component of interdisciplinary care. OUTCOMES: Eighty-seven percent of patients referred for neuropsychological assessment had an inaccurate neurocognitive diagnosis at the time of referral. Unmet and unrecognized mental health treatment needs were identified in over 77% of patients. In addition, acceptance was good for patients, caregivers, and clinicians. DISCUSSION: Teleneuropsychology is proving to be an excellent resource for clarifying cognitive and psychiatric diagnoses, and integrating individual strengths, weaknesses, and preferences into treatment and care plans used by other health care providers, patients, and caregivers.

Differences in anxiety among patients with early- versus late-onset Alzheimer's disease.

The authors sought to evaluate the incidence and correlates of anxiety in early-onset Alzheimer's disease (EOAD) versus the more typical late-onset AD (LOAD). A group of 23 EOAD and 22 LOAD patients were compared by the Neuropsychiatric Inventory Anxiety subscale. Demographic and disease-related relationships with anxiety were evaluated, as well as types of anxiety symptoms that were endorsed. EOAD patients had significantly more anxiety symptoms than LOAD patients. Among those with EOAD, anxiety was associated with male gender, higher Mini-Mental State Exam score, and separation from caregivers. Among LOAD patients, anxiety was associated with psychotic and activating psychiatric symptoms. These results have implications for the management and alleviation of anxiety in AD.