Nathan Hantke

Apathy and depression in subjective cognitive impairment (SCI) and mild cognitive impairment (MCI)

Background: Apathy, a behavioral syndrome characterized by amotivation and diminished goal-oriented behavior, and depression are commonly reported in MCI and dementia. Both apathy and depression have been associated with functional decline in these populations. Additionally, apathy is an important predictor of conversion from MCI to dementia. This study sought to investigate the relationships among apathy, depression and functional ability in geriatric patients with subjective and objective memory difficulties before progression to dementia. Methods: Participants were patients (n 1⁄4 40; mean age 1⁄4 74 + 7.9) with subjective memory complaints who were referred for neuropsychological assessment. All patients were proficient in English. The neuropsychological test battery included objective cognitive measures, as well as a self-report measure of mood, the Geriatric Depression Scale (GDS) and two familyreport measures of behavior: the Functional Activities Questionnaire (FAQ) and the Frontal Systems Behavior Scale (FrSBe). The FrSBe measures the frequency of behaviors associated with three frontal-behavioral domains: apathy (FrSBe-A), executive dysfunction (FrSBe-ED) and disinhibition (FrSBe-D). Participants were classified with Subjective Cognitive Impairment (SCI) if they performed within 1.5 standard deviations of the normative mean on objective cognitive measures. Participants were classified with Mild Cognitive Impairment-Amnestic (MCI-A) if they performed greater than 1.5 standard deviations below the normative mean on the delayed recall portion of the Hopkins Verbal Learning Test-Revised (HVLT-R), Logical Memory subtest of the Wechsler Memory Scale-III (WMS-III) or the Brief Visual Memory Test-Revised (BVMT-R).Results: The GDS correlated significantly with the FrSBe Total Score (r 1⁄4 .455) and each dimension of the FrSBe; FrSBe-A (r 1⁄4 .369), FrSBe-ED (r 1⁄4 .416) and FrSBe-D (r 1⁄4 .411). The GDS also correlated significantly with the FAQ (r 1⁄4 .376). The FAQ correlated significantly with the FrSBe-A (r 1⁄4 .472), but not with the FrSBe-ED or the FrSBe-D. Conclusions: In this sample of geriatric patients with subjective memory complaints and some with Amnestic MCI, significant relationships were found among self-report of depression and family members’ ratings of frontal systems behavior and functional capabilities. Specifically, apathy and depression were associated with functional ability. P2-271 TRAJECTORY CHANGE OF GLOBAL COGNITIVE FUNCTION PRIOR TO DEMENTIA DIAGNOSIS

Delta Activity at Sleep Onset and Cognitive Performance in Community-Dwelling Older Adults

STUDY OBJECTIVES Frontal intermittent rhythmic delta activity (FIRDA) has long been considered to be an abnormal variant in the electroencephalogram (EEG) among older adults. Prior work also indicates a predominance of slow wave EEG activity among patients with dementia. However, instability of state control occurring with aging generally and among many neurodegenerative diseases raises the possibility that FIRDA might represent the intrusion of sleep related elements of the EEG into the waking state. We examined delta activity at sleep onset (DASO) in community-dwelling, older adults without dementia, and examined whether this activity is related to poorer cognitive performance. METHODS 153 community-dwelling, older adults without dementia underwent overnight polysomnography and measures of global cognition, delayed verbal memory, information processing speed, attention, inhibition, verbal naming, and visuospatial ability. Delta activity during sleep/wake transitions (scored either as Waking or N1) was analyzed visually. RESULTS Participants were 83 women and 70 men, mean age 71.3 ± 0.6 y. DASO was present in 30 participants (19.6%). Age, years of education, sex, and body mass index did not differ between DASO (+) and (-) groups. Multiple regression analyses indicated faster reading of the Stroop color words in DASO (+) subjects (P = 0.007). None of the other cognitive domains differed between the two groups. CONCLUSIONS DASO was relatively common in our sample of community-dwelling, older adults without dementia. DASO was not associated with poorer performance on any cognitive domain. Instead, individuals with DASO demonstrated better performance on a simple reading task. Although these findings suggest that an abnormal EEG activity may represent normal variation, our work underscores the importance of distinguishing DASO from FIRDA when examining sleep in older adults. COMMENTARY A commentary on this article appears in this issue on page 725.

Subjective, but Not Objective Sleep is Associated with Subsyndromal Anxiety and Depression in Community-Dwelling Older Adults

OBJECTIVE To examine the relationship between subclinical anxiety and depressive symptoms and objective sleep architecture measures and subjective sleep reports in older adults. METHODS Community-dwelling older adults (N = 167) self-rated their current severity of anxiety symptoms, depressive symptoms, daytime sleepiness, and global sleep quality. Participants received overnight ambulatory polysomnography to assess sleep architecture. Multivariate linear regression models examined associations between anxiety and depressive symptoms and objective and subjective sleep measures. RESULTS Significant findings emerged for subjective sleep, with higher depression and anxiety scores associated with worse global sleep quality and greater anxiety scores associated with greater daytime sleepiness. No significant associations were observed between subclinical levels of anxiety or depressive symptoms with sleep architecture. CONCLUSION Subclinical levels of late-life anxiety and depression have distinct associations with subjective sleep disturbance. Findings implicate subjective measures of sleep quality and daytime sleepiness as stronger trait markers for subthreshold psychiatric symptoms than objective sleep biomarkers.

Altered Microstructural Caudate Integrity in Posttraumatic Stress Disorder but Not Traumatic Brain Injury.

Objective Given the high prevalence and comorbidity of combat-related PTSD and TBI in Veterans, it is often difficult to disentangle the contributions of each disorder. Examining these pathologies separately may help to understand the neurobiological basis of memory impairment in PTSD and TBI independently of each other. Thus, we investigated whether a) PTSD and TBI are characterized by subcortical structural abnormalities by examining diffusion tensor imaging (DTI) metrics and volume and b) if these abnormalities were specific to PTSD versus TBI. Method We investigated whether individuals with PTSD or TBI display subcortical structural abnormalities in memory regions by examining DTI metrics and volume of the hippocampus and caudate in three groups of Veterans: Veterans with PTSD, Veterans with TBI, and Veterans with neither PTSD nor TBI (Veteran controls). Results While our results demonstrated no macrostructural differences among the groups in these regions, there were significant alterations in microstructural DTI indices in the caudate for the PTSD group but not the TBI group compared to Veteran controls. Conclusions The result of increased mean, radial, and axial diffusivity, and decreased fractional anisotropy in the caudate in absence of significant volume atrophy in the PTSD group suggests the presence of subtle abnormalities evident only at a microstructural level. The caudate is thought to play a role in the physiopathology of PTSD, and the habit-like behavioral features of the disorder could be due to striatal-dependent habit learning mechanisms. Thus, DTI appears to be a vital tool to investigate subcortical pathology, greatly enhancing the ability to detect subtle brain changes in complex disorders.

Disentangling cognition and emotion in older adults: the role of cognitive control and mental health in emotional conflict adaptation.

Recent research suggests cognition has a bidirectional relationship with emotional processing in older adults, yet the relationship is still poorly understood. We aimed to examine a potential relationship between late‐life cognitive function, mental health symptoms, and emotional conflict adaptation. We hypothesized that worse cognitive control abilities would be associated with poorer emotional conflict adaptation. We further hypothesized that a higher severity of mental health symptoms would be associated with poorer emotional conflict adaptation.

Unlocking neurocognitive substrates of late-life affective symptoms using the research domain criteria: worry is an essential dimension

While investigations have sought to identify the distinct and shared contributions of anxiety and depression to neurocognitive processes in late life, less is known regarding the further contribution of worry, a unique and critical dimension of affective dysregulation. Capturing the full range of symptoms, as inspired by the NIH Research Domain Criteria (RDoC), may provide finer-grained information on inter-relationships among worry, anxiety and depression on neurocognitive processing in later life. The objective of this study was to determine if the dimensional trait of worry intensifies known negative associations of dimensional measures of anxiety and depressive symptoms with neurocognitive processes, specifically cognitive control and memory processes. Using a cross-sectional and observational design, this study was conducted within a translational research center located with a Veterans medical center in Northern California. One hundred and nineteen community-residing older adults ages 65–91 years participated, and were characterized with psychiatric and neurocognitive dimensional measures. Affective symptom severity was assessed with the Penn State Worry Questionnaire, the Beck Anxiety Inventory (BAI), and the Beck Depression Inventory-II. Primary neurocognitive outcomes were inhibitory control assessed using a Stroop paradigm and delayed verbal memory assessed with the Rey Auditory Verbal Learning Test. Secondary outcomes included other less frequently examined cognitive control mechanisms (working memory, information processing, and verbal fluency) and memory processes (visual delayed memory). Contrary to prediction, the dimensional trait of worry attenuated negative associations between anxiety and depressive symptoms and inhibitory control on the one hand, and between depressive symptoms and delayed verbal memory processes on the other. In the secondary models, symptom dimensions were not associated with other cognitive control or visual delayed memory processes. Our fine-grained approach, in line with the NIMH RDoC model, suggests the neurocognitive processes associated with dimensional measures of late-life affective symptoms are dissociable. Specifically, dimensional measures of worry operate independently from other anxiety and depression symptoms to reveal differential patterns of neurocognitive processes associated with affective dysregulation.

Longitudinal association of delta activity at sleep onset with cognitive and affective function in community-dwelling older adults

This investigation sought to determine whether delta activity at sleep onset (DASO) in the sleep electroencephalography of older adults represents normal variation or is associated with clinical pathology. To this end, we examined its longitudinal associations with cognitive and affective function in older adults without dementia.

Evidence of massive neural plasticity induced by exercise in MCI patients

ment. Reduction of atrophic changes of the temporal lobes: right up to 12%, left up to 11%. Reduction of AD severity with transition to TDR-1 stage. Figure 4. Same patient P., 37 years old, CT. 2 years after conservative treatment. Increase in the total degree of severety of atrophic changes of the temporal lobes up to 18%. Increased AD severity with transition to TDR-1 stage. Poster Presentations: P1 P250

Predictors of activities of daily living in older adults: The Frontal Systems Behavior Scale (FrSBe) and neuropsychological test performance

famous name and face retrieval in relation to performance on the FCSRT and to PiB retention (DVR, cerebellar reference) as a continuous variable in the precuneus, co-varying for age. Results: Retrieval of famous names (t(24)1⁄41.14, p 1⁄4 .267) and occupations (t(24)1⁄41.55, p 1⁄4 .135) was equivalent for MCI and CN subjects. Across the entire sample, retrieval of the names of famous individuals was positively related to both free recall (r1⁄4.723, p1⁄4.001) and cued recall on the FCSRT (r1⁄4.629, p1⁄4.003). Similarly, retrieval of occupations of famous individuals was positively related to free recall (r1⁄4.579, p1⁄4.007) and cued recall (r1⁄4.566, p1⁄4.009) on the FCSRT. Within the PiB-PET subgroup, increasing Abeta deposition was related to worse performance retrieving occupations (r1⁄4.555, p1⁄40.01) with a trend for retrieving famous names (r1⁄4.366, p1⁄4.074). Conclusions: Results suggest that semantic memory decline co-occurs with episodic memory decline and is furthermore associated with underlying Alzheimer’s pathology. Semantic memory decline may be a useful early marker in MCI and preclinical AD.