Ella Remund Wiger

Background: Heavy cannabis use may impact neurocognitive functions, particularly prefrontal and limbic systems responsible for risk/reward processing and executive function, which are essential for certain health behaviors, such as HIV prevention. Rigorous research into the effects of cannabis on neurocognitive functions remains limited, particularly among populations with a high burden of HIV. Objective: This study aims to (1) evaluate associations between cannabis use and neurocognition, (2) evaluate associations between cannabis use and engagement in HIV status–neutral care outcomes (eg, pre-exposure prophylaxis persistence, viral suppression), and (3) assess whether cannabis use motivations modify associations between cannabis use and engagement in HIV status–neutral care outcomes. Methods: This longitudinal cohort study is enrolling a community-based sample of individuals aged 16 to 29 years residing in Chicago using multiple recruitment strategies. Participants complete 3 in-person assessments annually over 2 years that include (1) computer-assisted questionnaires, (2) neurocognitive assessments (functional magnetic resonance imaging, executive function tasks), and (3) biospecimen collection. Triangulation approaches combine objective and self-reported measures. Results: The Frontal Lobe Outcomes and Well-Being (FLOW) Study was funded by the National Institutes of Health in April 2023, with data collection commencing in October 2023. As of April 2026, 148 participants have been enrolled and completed baseline assessments, with 63 participants completing their first follow-up appointment and 4 participants completing their second follow-up appointment. Following a temporary administrative pause from March to August 2025 and subsequent federal review confirming regulatory compliance, the study resumed operations in July 2025. Recruitment is currently ongoing, with data collection expected to continue through June 2027. Preliminary analyses are pending completion of longitudinal data collection. Conclusions: This study addresses critical knowledge gaps by examining potential associations between cannabis use, neurocognition, and HIV. While geographic specificity, structural barriers, measurement challenges, and sample size constraints present some limitations, our methodological approaches—including longitudinal design, triangulation of both objective and self-reported measures, and rigorous neurocognitive assessments—strengthen the investigation. Findings will advance understanding of how cannabis use impacts neurocognition and HIV-related health behaviors, potentially informing targeted interventions that address both substance use and HIV transmission.

Background: Doxycycline postexposure prophylaxis (doxy-PEP) is a low-cost, effective strategy for preventing syphilis and other bacterial sexually transmitted infections among men who have sex with men and transgender women, yet doxy-PEP remains underused by young black sexual and gender minorities (YBSGM). This analysis examined sociodemographic, sexual health, and substance use factors associated with interest in doxy-PEP among a human immunodeficiency virus (HIV) status–neutral cohort of YBSGM. Methods: The Neighborhoods and Networks Phase 2 (N2P2) cohort included YBSGM, and our primary outcome was interest in doxy-PEP. Generalized linear models were fit to calculate the unadjusted and adjusted relative risks (RRs) between interest in doxy-PEP and sociodemographic and health factors. Results: A total of 538 participants were included in the analysis, with 59.9% reporting interest in doxy-PEP. Participants interested in doxy-PEP were older (RR, 1.02 [95% confidence interval (CI), 1.00–1.04]; P = .04), more likely to be living with HIV (1.25 [1.08–1.44]; P < .01), and more likely to have a history of syphilis (1.45 [1.23–1.70]; P < .01). Self-report stimulant use (RR, 1.28 [95% CI, 1.15–1.53]; P < .01) and group sex (1.32 [1.15–1.53]; P < .01) were greater among those interested in doxy-PEP. When adjusted for age, HIV status, and stimulant use, history of syphilis (adjusted RR, 1.17 [95% CI, 1.05–1.31]; P = .01) and group sex (1.14 [1.02–1.28]; P = .02) remained associated with interest in doxy-PEP. Conclusions: YBSGM who were interested in doxy-PEP were more likely to have had a syphilis diagnosis and participate in group sex. YBSGM with these risk factors represent an important demographic for the scale-up of doxy-PEP use.

Adaptively and flexibly modifying one's behavior depending on the current demands of the situation is a hallmark of executive function. Here, we examined whether pigeons could flexibly shift their attention from one set of features that were relevant in one categorization task to another set of features that were relevant in a second categorization task. Critically, members of both sets of features were available on every training trial, thereby requiring that attention be adaptively deployed on a trial-by-trial basis based on contextual information. The pigeons not only learned to correctly categorize the stimuli but, as training progressed, they concentrated their pecks to the training stimuli (a proxy measure for attention) on those features that were relevant in a specific context. The pigeons selectively tracked the features that were relevant in Context 1-but were irrelevant in Context 2-and they selectively tracked the features that were relevant in Context 2-but were irrelevant in Context 1. This adept feature tracking requires disengaging attention from a previously relevant feature and shifting attention to a previously ignored feature on a trial-by-trial basis. Pigeons' adaptive and flexible performance provides strong empirical support for the involvement of focusing and shifting attention under exceptionally challenging training conditions.