Correlação entre potência absoluta alfa induzida por EMT (5HZ) e estimativa do tempo

Abstract

Behavioral traits such as inattention and/or hyperactivity, characteristic of the ADHD spectrum, even when present at subclinical levels (traits), have been linked to alterations in frontoparietal neural network functioning and can impact executive functions and time perception. Repetitive Transcranial Magnetic Stimulation (rTMS) is a promising neuromodulation technique, but its effects on time perception and neurophysiological activity in individuals with ADHD traits require further investigation. Objective: To investigate the effects of a single session of 5 Hz rTMS, compared to a Sham (placebo) condition, on performance in a time estimation task and on absolute alpha band power in university students with elevated ADHD traits. Methods: A randomized, crossover, placebo-controlled (Sham) study was conducted with 18 university students (18-29 years old) with elevated ADHD traits (>80th percentile on the ETDAH-AD). Participants received active 5 Hz rTMS and Sham stimulation over F3 and PZ in separate sessions (separated by 7 days). Time estimation task performance (1s, 4s, 7s, 9s intervals) and Electroencephalography (EEG) were assessed before and after each intervention, analyzing Absolute Error (AE), Relative Error (RE), and absolute alpha band power (Total, Alpha-1, Alpha-2) across multiple cortical regions. Results: For AE, rTMS significantly reduced the error in the 4s and 9s intervals (p<0.001). RE was significantly lower (indicating improvement) with active rTMS in the 1s (p=0.0029), 4s (p<0.0001), and 9s (p<0.0001) intervals compared to Sham. In the neurophysiological analysis, 5 Hz rTMS induced significant modulations in the absolute power of Total Alpha, Alpha-1, and Alpha-2 bands, involving increased power in central-parietal-temporal regions and frontal modulation. Conclusion: A single session of 5 Hz rTMS modulates cortical alpha oscillatory activity in a region-specific manner and enhances the precision of time perception in university students with elevated ADHD traits. These findings suggest underlying neurophysiological mechanisms for temporal deficits associated with ADHD traits and reinforce the potential of rTMS as an investigational and targeted intervention tool.