Imran, A. | bioRxiv Science

bioRxiv2024

Assessing Cognitive Functions Remotely Using a Music-Game-Like Program

There is a growing need to develop ways of assessing cognitive functions remotely and providing interventions using a web-based approach. The Ipsilon Test is a music-based cognitive assessment and training tablet application. On each trial, it presents simplified musical notation with colours, spatial cues, and gestural references so that users can translate spatial information into motor actions by tapping on the screen. In this study, we examined the correlation between the performance of a group of healthy older adults on the Ipsilon test and standard measures of cognitive function--a total of 30 participants aged 58 and over were recruited for the study. Before and after one week of training using the web-based program Ipsilon, all participants completed an online version of the Montreal Cognitive Assessment (MoCA) and the visual Stroop task. Of the participants recruited, 22 participants completed the Ipsilon training and cognitive testing. In our sample, performance on the Ipsilon test was generally high, with all participants scoring above the chance level. Importantly, we found a correlation between Ipsilon test performance and pre-Ipsilon MoCA scores. In addition, participants who scored higher on the Ipsilon test also showed improvement in the visual Stroop task after Ipsilon training, particularly in the ability to inhibit irrelevant information. These results suggest the Ipsilon test is a practical web-based cognitive assessment and training tool. Future research will explore its relationship with other cognitive tests and its diagnostic power for differentiating individuals with normal cognition from those with cognitive disorders.

neuroscience↗

bioRxiv2023

Immunogenicity of COVID-19 vaccines and their effect on the HIV reservoir in older people with HIV

Older individuals and people with HIV (PWH) were prioritized for COVID-19 vaccination, yet comprehensive studies of the immunogenicity of these vaccines and their effects on HIV reservoirs are not available. We followed 68 PWH aged 55 and older and 23 age-matched HIV-negative individuals for 48 weeks from the first vaccine dose, after the total of three doses. All PWH were on antiretroviral therapy (cART) and had different immune status, including immune responders (IR), immune non-responders (INR), and PWH with low-level viremia (LLV). We measured total and neutralizing Ab responses to SARS-CoV-2 spike and RBD in sera, total anti-spike Abs in saliva, frequency of anti-RBD/NTD B cells, changes in frequency of anti-spike, HIV gag/nef-specific T cells, and HIV reservoirs in peripheral CD4+ T cells. The resulting datasets were used to create a mathematical model for within-host immunization. Various regimens of BNT162b2, mRNA-1273, and ChAdOx1 vaccines elicited equally strong anti-spike IgG responses in PWH and HIV- participants in serum and saliva at all timepoints. These responses had similar kinetics in both cohorts and peaked at 4 weeks post-booster (third dose), while half-lives of plasma IgG also dramatically increased post-booster in both groups. Salivary spike IgA responses were low, especially in INRs. PWH had diminished live virus neutralizing titers after two vaccine doses which were rescued after a booster. Anti-spike T cell immunity was enhanced in IRs even in comparison to HIV- participants, suggesting Th1 imprinting from HIV, while in INRs it was the lowest. Increased frequency of viral blips in PWH were seen post-vaccination, but vaccines did not affect the size of the intact HIV reservoir in CD4+ T cells in most PWH, except in LLVs. Thus, older PWH require three doses of COVID-19 vaccine to maximize neutralizing responses against SARS-CoV-2, although vaccines may increase HIV reservoirs in PWH with persistent viremia.

immunology↗