At P4 (Fig. 3b) we also observed a significant Group x Condition
interaction (p < .049) in the time-range covering from
304 ms to 336 ms (Table a Suppl El Mat). Its decomposition revealed
significant differences between conditions (Table c Suppl El Mat) in
highs (NH vs R and Post) who increased their HEP amplitude, and in lows
(Post vs R and IND1), who decreased it.
Moreover, we observed a significant Condition effect (p< .004) regarding both groups (Fig. 4, Table a Suppl El Mat)
at Cz (Fig. 4) in a time-window ranging from 288 ms to 360 ms after
R-peak. The most extreme differences between the HEPs were between the R
and the IND2 conditions, with R exhibiting the higher values of HEP and
IND2 the lower ones. Among the other conditions, NH significantly
differed from R (288-346) ms range and from B (352-360) ms range.
Interestingly, the first and the second halves of the induction (IND1
and IND2) differed from B in different time windows: i.e., (296-320) ms
for IND1 and (328-353) ms for IND2.