Sensorimotor adaptation is a type of learning that allows sustaining accurate movements by adjusting motor output. This allows the brain to adapt to temporary changes when engaged in a certain task. Within sensorimotor adaptation, visuomotor adaptation (VMA) is one’s ability to correct a visual perturbation. In this study, we present preliminary results on the effects of VMA with the control group, compared to groups undergoing trigeminal nerve stimulation (TNS) or SHAM (placebo) effects. Twenty-two healthy subjects with no past medical history participated in this study. Subjects performed a visuomotor rotation task, which required gradually adapting to a perturbation between hand motion and corresponding visual feedback. Five total blocks were completed: two familiarization blocks, one baseline block, one rotation block with a 30◦ counterclockwise rotation, and one washout block with no rotation. The control group performed better than the 120 Hz (TNS) and SHAM groups due to less directional error (DE) on the respective learning curves. Additionally, the control group adapted faster (less DE) than the SHAM groups that either felt stimulation, or did not feel the stimulation. The results yield new information regarding VMA which can be used in the future when comparing sensorimotor adaptation and its many applications.

When behaving in a goal-directed manner, the ability to suppress specific inappropriate actions is crucial to human motor function. Motor inhibition, or the repression of specific actions prior to and during onset of a motor command, allows humans to quickly respond and adapt their decisions to unexpected changes within an environment. Research investigating the faciliatory effects of anodal transcranial direct current stimulation (tDCS), a non-invasive stimulation technique that can potentially modulate the activity of target regions of the brain, on inhibition have been well-documented in the use of conventional or 1x1 tDCS devices. However, the the advent of High-Definition tDCS (HD-tDCS), which is claimed to enhance spatial precision through the usage of multiple smaller electrodes, has led to increased interest in its effects on motor inhibition and related cognitive processes. HD-tDCS may offer a more targeted approach to modulating neural circuits involved in motor planning and inhibitory control, such as the pre-Supplementary Motor Area (pre-SMA) and dorsolateral prefrontal cortex (DLPFC). This study aims to investigate the effects of anodal HD-tDCS over the pre-SMA on motor inhibition using the stop-signal task. By examining response times, error rates, and Stop Signal Reaction Time (SSRT), we seek to understand the potential advantages of HD-tDCS in modulating motor-related cognitive processes. These findings have implications for refining brain stimulation techniques and developing targeted interventions for conditions involving impaired inhibitory control.