The individual replicability of mismatch negativity at short and long inter-stimulus intervals.
OBJECTIVE
The individual replicability of the mismatch negativity (MMN) event-related brain potential (ERP) was studied at two different inter-stimulus intervals (ISIs), to establish its potential value for routine clinical evaluation of sound discrimination and auditory sensory memory.


METHODS
Ten healthy young subjects were presented sequences of 3 stimulus trains, in two recording sessions approximately 1 month apart. The stimuli in the trains were delivered at an ISI of 300 ms, whereas the inter-train intervals (ITIs) were 0.4 s and 4.0 s in different blocks. ERPs were averaged to standard (75 ms) and deviant (25 ms) tones started equiprobably the stimulus trains.


RESULTS
Significant Pearson product-moment correlations coefficients were found between sessions at all scalp locations for the short ITI, when the MMN was quantified as the mean amplitude in the 100-200 ms latency window around its peak. However, none of the correlations reached significance for the longer ITI.


CONCLUSIONS
MMN appears to be a reliable measure for single-case assessment and follow-ups when obtained at short ISIs and quantified as an integrated window of neuroelectric activation over a temporal span.
Escera
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C
Neurodynamics Laboratory, Department of Psychiatry and Clinical Psychobiology, University of Barcelona, P. Vall d'Hebron 171, 08035 Barcelona, Catalonia, Spain. cescera@psi.ub.es
Yago
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E
Polo
M D
MD
Grau
C
C
D000161:Acoustic Stimulation; D000328:Adult; D000704:Analysis of Variance; D001921:Brain / Q000502:physiology*; D004569:Electroencephalography; D005072:Evoked Potentials, Auditory / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D013997:Time Factors