Effects of a Motor Cortex Neuromodulation Approach on Neuromotor and Neurocognitive Performance in Latinx People with HIV

Background: Human Immunodeficiency Virus (HIV) infection has been known to impact both motor and cognitive systems and cause motor and cognitive alterations (MCAs). Transcranial direct current stimulation (tDCS), mainly when applied to the prefrontal cortex, has shown promising results in improving gait, balance, and executive functions in individuals with HIV. Previous studies suggest that integrating a task designed to stimulate higher cognitive centers in combination with tDCS could potentially enhance these effects. Purpose: The objective of this study was to investigate whether the combination of tDCS with a tracking task, when applied to the prefrontal cortex, effectively enhances reaction time and HIV dementia scale (HDS) scores (motor-cognitive) components in individuals living with HIV. Methods: The study involved nine female and one male participants living with HIV, with an average age of 58.9 ± 4.3 years. To assess the impact of tDCS on RT and motor cognition, each participant was evaluated both before and after the administration of tDCS with the HDS. Participants' primary goal for the reaction time components was to respond quickly and accurately to color changes by tapping the pod that lit up green. This task was performed while applying tDCS to the prefrontal cortex, allowing researchers to focus simultaneously on cognitive reaction speeds and the physical effects of neuromodulation. Results: Upon analysis, significant differences were noted between pre and post-tDCS of the HDS scores. The data further revealed substantial improvements in reaction time, hits, and strikes after the tDCS application. Conclusion: The results of this study demonstrated that tDCS can potentially improve neurocognitive and motor function in individuals with HIV. However, the study recommends that tDCS treatments be applied over a more extended period than in this study.