Cognitive Remediation

The goal of this clinical trial is to determine if a neuroscience-based computerized cognitive remediation ("brain training") program can treat neurocognitive dysfunction (i.e., memory or thinking difficulties) that emerges in some older adults following a viral infection. The main questions it aims to answer are: * Does computerized cognitive remediation improve cognitive performance and day-to-day functioning in older adults with postviral neurocognitive dysfunction? * Will treatment effects be maintained over time, leading to better long term cognitive outcomes? * Does the treatment lead to reductions in blood-based markers of inflammation as a potential mechanism of cognitive symptom improvement? * Can the treatment be optimized and refined based on feedback from participants to improve user (patient) experience? Researchers will compare the computerized cognitive remediation program to an active computer-based control condition (alternative computer activities) to see if the computerized cognitive remediation program works to treat postviral neurocognitive dysfunction. Participation takes approximately 43-48 hours over 7 months, with most activities (40-46 hours) completed within the first 7-8 weeks, including: * Initial intake visit: Eligibility confirmation (\~2-3 hours) * Computer activities: About 5 hours per week for \~6 weeks (total \~30 hours) completed on a computer tablet provided by the study and loaned to participants for use during the treatment phase * Weekly remote check-in meetings: \~30 minutes each during treatment * Blood draws: Two sessions (before and after treatment), \~20-30 minutes each * Three research visits: Pre-treatment, post-treatment, and 6-month follow-up (\~2-3 hours each, including assessments of cognitive, emotional, and daily functioning)