Acute tai chi practice and emotional stimulus processing in adults with and without tai chi experience: An ERP study

Tai Chi combines coordinated movement, breathing regulation, and sustained attention. It remains unclear whether prior Tai Chi experience is associated with different immediate neural responses to picture stimuli after a shared practice session. Event-related potentials (ERPs) were recorded while 39 healthy adults viewed high-arousal negative and neutral pictures from the Chinese Affective Picture System before and after a 30-min simplified Tai Chi session. Negative pictures were also the low-probability stimuli. Seventeen participants had at least 1 year of Tai Chi experience and 22 had no prior experience. The early posterior negativity (EPN), quantified as signed mean amplitude from 200 to 300 ms at P7, O1, P8, and O2, was the theory-guided primary outcome; N2, P300, and the late positive potential (LPP) were secondary outcomes. The EPN showed a Time × Picture Category × Group interaction, F(1, 37) = 4.512, p = .040, ηp² = 0.109. The negative-minus-neutral EPN contrast (signed negative amplitude minus signed neutral amplitude) decreased in experienced participants and increased numerically in non-experienced participants. In the primary follow-up, the contrast-change score differed between groups, t(37) = -2.124, p = .040, d = -0.686, 95% CI [-1.33, -0.03]. Trial-matched resampling retained the direction of the group difference, but statistical significance was not stable. N2, P300, and LPP did not show the same group-related interaction. The EPN finding is preliminary and requires replication. It describes an association between prior Tai Chi experience and pre-to-post change in early picture-category differentiation within this specific CAPS task, not a general emotional-processing effect, a Tai Chi-specific effect, a reduction in negative emotion, or a therapeutic benefit.