Rate-Associated Differences in Within-Session Motor-Inhibitory Performance: Exploratory Role of Affective Temperament

Response inhibition is often summarized as a single individual score, although performance may change within a session as temporal demand and repeated exposure vary. We examined whether change in No-Go motor performance differed across stimulus-rate conditions and was associated with affective temperament in 53 physically active participants, predominantly young adults. Participants completed three blocks of an elbow-based Go/No-Go task; four 50-stimulus series were administered at 40, 50, 60, and 70 bpm in randomized order. The analysis included 636 series-level observations and 6360 No-Go trials, including 3185 commission errors (50.1%). Commission-error occurrence was given primary interpretive priority; conditional error duration was considered complementary, and the pragmatically weighted integrated error index was treated as a secondary composite. Error burden differed across stimulus-rate conditions, and rate-by-block interactions emerged for commission-error occurrence (trial-level GEE; Wald χ²(6) = 25.96, p < 0.001), conditional error duration (Wald χ²(6) = 14.96, p = 0.021), and the integrated index (Wald χ²(6) = 30.40, p < 0.001). Direct contrasts confirmed larger Block-1-to-Block-3 reductions at 50-70 bpm than at 40 bpm. A secondary exploratory participant-level analysis suggested that higher irritable temperament was associated with a more negative Block-3-minus-Block-1 change (β = -0.82, 95% CI -1.39 to -0.26, FDR-adjusted p = 0.020), although the corresponding moderation did not survive global correction across all temperament tests. Overall, the data indicate rate-associated differences in within-session No-Go motor performance; temperament-related findings remain exploratory.