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Oades, R.D., Dittmann-Balcar, A. & Zerbin, D. (1995) The topography of 4 subtraction ERP-waveforms derived from a 3-tone auditory oddball task in healthy young adults. Int. J. Neurosci., 81, 265-281. (request a copy) . (view) Introduction:
Five components were studied in 4 subtraction waveforms derived from
ERPs obtained in passive and active conditions of a 3-tone oddball task
(common=70%, C, 0.8 KHz; deviant=15%, D, 2 KHz; 1.4 KHz=15%, t, also
used as a target (T)).
Results:
There were main site effects in normalized data in all cases (not
P2 and N2 latency). There were separate frontal and posterior contributions
to P1, with the former emphasized where target comparisons
were involved. Conclusions: Thus an attentional effect(controlled processing) is evident as early as 60 ms. Target features modify the anteroposterior distribution of positivity and negativity for the early components and in the lateralization of P3-like positivity. A comparison of waveforms by latency of potential shift (running t-test) vs. peak identification (MANOVA) is illustrated and discussed. D/C (MMN) and T/t (Nd) waveforms, rather than T/D or G-wv (PN & Goodin waveforms) waveforms are recommended for distinguishing comparator mechanisms for stimulus- and task-relevant features. See other reports on MMN in healthy subjects (1995a, 1995b, 1997a) and in schizophrenia (1993. 1996, 1997b ) See other reports on Nd in healthy subjects (1995b, 1997a), and in schizophrenia (1991 ,1996) . |