The learning effect found here was remarkably early and robust, the
response peaking at 50 ms after the critical syllable onset (when the native
stimuli diverged from their environment) across the different attention
conditions. The enhanced response in this latency range has
previously been linked to automatic activation of words' lexical memory
traces, demonstrating that the lexical status (known word vs. pseudoFig.
2. Cortical source activation underlying pseudo-word learning. Average of individual LORETA source estimations of the significant response change for pseudo-words 40–60 ms post
second syllable onset. Changes in source current densities between early and late exposure times for all word types in the source locations are shown in the middle. The activation increase
for pseudo-words was significant in the left inferior frontal and posterior temporal locations. The crosshairs indicate the centre of the ROI used in the statistical analysis. Error bars are SEM.
LH = left hemisphere, RH = right hemisphere.
L. Kimppa et al. / NeuroImage 118 (2015) 282–291 287
wo