In 10 healthy controls we determined MT and I1 mV with R-R and PEST using a blinded crossover design, and performed within-session serial PEST measurements of MT.
There was no significant difference between methods for MT (52.6 ¡À 2.6 % vs. 53.7 ¡À 3.1 % ; p = 0.302; % maximum stimulator output; R-R vs. PEST, respectively) or I1 mV (66.7 ¡À 3.0 % vs. 68.8 ¡À 3.8 % ; p = 0.146). There was strong correlation between R-R and PEST estimates for both MT and I1 mV. R-R required significantly more stimuli than PEST. Serial measurements of MT with PEST were reproducible.
PEST has the advantage of speed without sacrificing precision when compared to the R-R method, and is adaptable to other SI targets.
Our results in healthy controls add to increasing evidence in favour of adaptive threshold-hunting methods for determining SI.