Browsing by Author "Tierney, Savanna M."

Now showing 1 - 2 of 2

Semantic Memory in HIV-Associated Neurocognitive Disorders: an Evaluation of the "Cortical" versus "Subcortical" Hypothesis
(2017-08) Tierney, Savanna M.; Woods, Steven P.; Massman, Paul J.; Hasbun, Rodrigo
While HIV- associated neurocognitive disorders (HAND) have historically been characterized as a subcortical process, there is some evidence to suggest that the cortical regions that support semantic memory may also be affected. The current study examined the effects of HAND on semantic memory. Participants were (N = 459) separated into three groups based on neurocognitive status defined by the Frascati criteria: HIV+ individuals with HAND (n = 85), HIV+ individuals without HAND (n= 191), and HIV negative individuals (n=183). All participants completed the Boston Naming Test (BNT) and the Famous Faces subtest of the Kauffman Adolescent and Adult Intelligence Test (KAIT). Analyses of errors committed on the BNT were conducted to further characterize the nature of semantic memory differences across groups. Linear regressions revealed a significant adverse effect of HAND on total scores on the BNT and the KAIT (all ps < .01). Analyses of BNT errors showed that individuals with HAND committed increased rates of semantically-related errors as compared to the other two groups (all ps < .05). However, there were no group differences in rates of visually based errors, more commonly observed in subcortical diseases (all ps > .10). Findings regarding the cognitive correlates of semantic memory show that executive (rs = -.24, p = .02), speed of processing (rs = -.31, p = .004), and learning (at trend level) domains were shown to be associated with BNT performance, while only the learning domain (rs = -.28, p = .01) was significantly related to KAIT scores within the HAND+ group. Results suggest that HAND may impose adverse effects on individuals’ object naming and identification abilities and suggest that there are mild semantic deficits in HAND that parallel traditional cortical diseases such as Alzheimer’s Disease.
WHERE AM I AND HOW DID I GET HERE? THE EFFECTS OF AGING ON INTERNET-BASED TRANSPORTATION NAVIGATION SKILLS
(2020-08) Tierney, Savanna M.; Woods, Steven P.; Medina, Luis D.; Damian, Rodica I.; Collins, Robert L.
Difficulties using the internet can represent a barrier to optimal daily functioning, particularly for older adults, who may experience age-related neurocognitive changes. While much of the research on aging and internet task performance has focused on information searching, internet transit planning and navigation may also be relevant for older adults. The current study examined the effects of older age on internet navigation skills using a novel transit planning paradigm, explored neurocognitive correlates of internet transit navigation performance, and assessed the potential benefit of brief experimental support designed to enhance internet transportation planning ability and performance. Participants included 40 older and 50 younger adults who completed three thematically interrelated transit internet navigation tasks via a live San Francisco Transit website. Regression analyses showed that older adults were less accurate and also slower to complete internet transit tasks compared to younger participants at the level of large effect sizes. Among all participants, internet transit speed and accuracy demonstrated small-to-medium positive associations with standard clinical measures of episodic learning and memory. For a fourth transit task, participants in each group were randomized into either a control condition or into a condition in which they received a brief experimental support session to facilitate the planning and execution of the task. A significant age by condition term was observed, whereby the planning supports were more beneficial in the younger group than in the older group. Findings suggest that older adults experience difficulties quickly and accurately using a transit website to plan transportation routes, which may be related to their ability to learn and recall information. Given the lack of efficacy of a brief, planning-based support strategy among older adults, future work might examine the potential benefits of effective learning and memory strategies (e.g., spaced retrieval practice, elaboration).