Figure 1. Effects of diazepam on homonymous short-latency afferent inhibition (SAI) produced by median nerve stimulation at different interstimulus intervals (ISIs).

Data are means (n = 11) at baseline (○) and 1.5 h after diazepam administration (▪), error bars are standard deviations. SAI is reported by the amplitude of the conditioned motor evoked potential (MEP) normalised to the unconditioned test MEP. A repeated measures analysis of variance (ANOVA) model with the within-subject effects of TIME (baseline, 1.5 h after diazepam intake) and ISI (5 intervals) shows a significant effect both of TIME (F_1,50= 9.72, P < 0.05) and of ISI (F_4,50= 4.76, P < 0.05). Diazepam increases the amount of SAI at ISIs of N20 +4 ms and N20 +6 ms (*P < 0.05). The mean N20 latency was 18.5 ± 1.3 ms.