Neurobiological mechanisms in cognitive regulation: A tVNS Approach

The locus coeruleus (LC), a brainstem region critical for regulating arousal and attentional processes, plays a central role in theories of cognitive functioning. However, the lack of direct and reliable methods to manipulate LC activity has limited empirical testing of these theories. This project aims to address this gap by leveraging transcutaneous vagus nerve stimulation (tVNS), a non-invasive neuromodulation technique that can increase LC activity. In the first phase, the project focuses on methodological experiments to identify the most effective tVNS parameters for short-term LC stimulation. The second phase involves theory-driven experiments utilizing tVNS to modulate LC activity and examine two competing hypotheses about its role in perceptual decision-making. The gain hypothesis posits that LC activity enhances the signal-to-noise ratio for task-relevant stimuli, improving both decision speed and accuracy, whereas the urgency hypothesis suggests that LC activity accelerates decision-making at the cost of accuracy. By combining methodological and theory-driven experiments, this project seeks to provide novel insights into the mechanisms of LC activity and its role in cognition. These findings have the potential to advance our understanding of neuromodulatory processes and inform future applications of tVNS in cognitive neuroscience.