Associations between anxiety, centromedial amygdala volume, and complex verbal fluency in middle-aged to older adults.

Symptoms of anxiety are related to decreases in cognitive performance in middle-aged to older adults (i.e., ages 50 and older; MOA). Verbal fluency (VF), assessed with the Delis-Kaplan Executive Function System (D-KEFS) Category Switching (VF-CS) task, captures elements of executive function such as semantic memory, response initiation and inhibition, and cognitive flexibility. The present study examined the link between anxiety symptoms and VF-CS to better understand how this association affects such executive functions in MOA. We hypothesized that higher subclinical Beck Anxiety Inventory (BAI) scores would be associated with lower VF-CS. To further investigate the underlying neurobiological basis of an expected inverse relationship, total amygdala volume, centromedial amygdala (CMA) volume, and basolateral amygdala (BLA) volume were examined as they related to VF-CS scores on the D-KEFS. Based on extant research on connectivity and functioning between the CMA and BLA, we hypothesized that larger BLA volumes would be associated with lower anxiety scores and exhibit positive relationships with VF-CS. A sample of 63 MOA were recruited from the Providence, Rhode Island area as a part of a parent study on cardiovascular diseases. Participants completed self-report measures about physical and emotional health, a neuropsychological assessment, and a magnetic resonance imaging scan (MRI). Multiple hierarchical regressions were performed to examine relationships between variables of interest. Contrary to hypotheses, no significant relationship emerged between VF-CS and BAI scores, and BLA volume was not associated with either BAI scores or VF-CS. However, a significant positive relationship was observed between CMA volume and VF-CS. The significant relationship found between CMA and VF-CS may reflect the upward slope of the quadratic relationship between arousal and cognitive performance on the Yerkes-Dodson curve. These findings newly implicate CMA volume specifically as a possible neuromarker linking emotional arousal and cognitive performance in MOA.

Estimating premorbid intelligence in persons with traumatic brain injury: an examination of the Test of Premorbid Functioning.

Knowledge of intelligence is essential for interpreting cognitive performance following traumatic brain injury (TBI). The Test of Premorbid Functioning (ToPF), a word reading test co-normed with the Wechsler Adult Intelligence Scale 4th Edition (WAIS-IV), was examined as a tool for estimating premorbid intelligence in persons with a history of TBI. Fifty-two participants with mild, moderate, or severe TBI were administered the ToPF and WAIS-IV between two weeks and 19 months post-injury. The independent ability of the ToPF/demographic score and the Verbal Comprehension Index (VCI) to predict WAIS-IV Full Scale IQ (FSIQ) was examined, as were discrepancies between ToPF and WAIS-IV scores within and between participants. The ToPF/demographic predicted FSIQ accounted for a significant proportion of variability in actual FSIQ, above and beyond that accounted for by education or time since injury. ToPF and WAIS-IV scores did not differ by injury severity. In our sample, the ToPF/demographic predicted FSIQ underestimated intelligence in a substantial portion of our participants (31%), particularly in those with high average to superior intelligence. Finally, VCI scores were more predictive of actual FSIQ than the ToPF/demographic predicted FSIQ. The ToPF frequently underestimated post-injury intelligence and is therefore not accurately measuring premorbid intelligence in our sample, particularly in those with above average to superior intelligence. Clinicians are encouraged to administer the entire WAIS-IV, or at minimum the VCI subtests, for a more accurate measure of intelligence in those with above average intelligence and history of TBI.

Rey Tangled Line Test: A measure of processing speed in TBI.

OBJECTIVE: Neuropsychological assessment plays a key role in characterizing and detecting cognitive impairment after traumatic brain injury (TBI). The Rey Tangled Line Test (RTLT), an understudied neuropsychological assessment thought to be capable of detecting visual processing deficits, was examined to determine which cognitive abilities may contribute to performance on the test in participants with a history of TBI. METHOD: One-hundred participants with a history of mild to severe TBI were administered a battery of neuropsychological tests assessing attention, executive functioning, memory, visual construction, motor functioning, and processing speed between 30 days and 5 years postinjury. An exploratory principal components analysis (PCA) was performed to determine which cognitive tests the RTLT was most highly associated with. RESULTS: No difference in RTLT latency was present between mild and moderate/severe TBI. The PCA resulted in 5 factors. RTLT latency had a significant primary factor loading on the "processing speed" factor, and a secondary loading on the "motor" factor. Forty-two percent of participants had an impaired latency score. CONCLUSIONS: RTLT latency appears to measure processing speed, and likely aspects of motor functioning, in our sample. The RTLT may be useful as a rapid assessment in individuals with a history of TBI to detect cognitive deficit before initiating further cognitive testing or rehabilitation efforts. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Urinary tetrahydrocannabinol is associated with poorer working memory performance and alterations in associated brain activity.

Worldwide, cannabis is one of the most widely used psychoactive substances and cannabis use has been implicated in poorer performance in several cognitive domains, including working memory (WM). However, the neural mechanisms underlying these WM decrements are not well understood and the current study investigated the association of cannabis involvement with WM performance and associated neural activation in the Human Connectome Project (N = 1038). Multiple indicators of cannabis involvement were examined in relation to behavioral performance and brain activity in a visual N-back task using functional magnetic resonance imaging. A positive urine drug screen for tetrahydocannabinol (THC+ status), the principal psychoactive constituent in cannabis, was associated with worse WM performance and differential brain response in areas previously linked to WM performance. Furthermore, decreases in blood-activation-level-dependent (BOLD) signal in WM task-positive brain regions and increases in task-negative regions mediated the relationship between THC+ status and WM performance. In contrast, WM performance and BOLD response during the N-back task were not associated with total lifetime cannabis use, age of first use, or other indicators of involvement, suggesting that the effects of cannabis on WM were short-term residual effects, rather than long-term persistent effects. These findings elucidate differential influences of cannabis involvement on neurocognition and have significant potential implications for occupational performance in diverse settings.

Concurrent Validity of New Subscale Scores for the Booklet Category Test.

The Booklet Category Test (BCT) is a neuropsychological test of cognitive dysfunction that provides only one overall error score indicative of global impairment. It does not, however, delineate specific domains that might be impaired. The aim of this study is to concurrently validate 13 new BCT subscales using legacy instruments in patients with nonpenetrating traumatic brain injury (TBI). Eighty-nine patients with mild, moderate, and severe TBI completed a battery of neuropsychology tests. Partial correlations controlling for age were performed and there were significant correlations between the a priori selected scores from legacy measures of major cognitive domains and both BCT total errors and subscale scores. Additional analysis showed that several subscales were able to differentiate between performance levels on the legacy measures. Overall, our results showed that the subscales measured cognitive skills beyond global impairment, supporting the use of the BCT subscales in a population with TBI.