Performance metrics obtained at each of the pairs of stimulus sites under 3 different conditions of concurrent stimulation (0, 25 Hz, and 200 Hz). Panel A: Hand dorsum. Note that TOJ thresholds are significantly elevated with the presence of both the 25 Hz and 200 Hz conditioning stimuli (p < 0.01). Panel B: Unilateral digit tips 2 & 3. The 200 Hz conditioning stimulus, although it has an impact on the TOJ measure (p < 0.01) does not have as pronounced an effect on the digit tips as on the hand dorsum. Panel C: Bilateral digit tips 2. Conditioning stimuli had no significant effect when applied on bilateral digit tips (p > 0.21).