PMID- 8416067
OWN - NLM
STAT- MEDLINE
DCOM- 19931119
LR  - 20190830
IS  - 0048-5772 (Print)
IS  - 0048-5772 (Linking)
VI  - 30
IP  - 1
DP  - 1993 Jan
TI  - Distortion of ERP averages due to overlap from temporally adjacent ERPs: analysis 
      and correction.
PG  - 98-119
AB  - In studies of event-related potentials (ERPs), short interstimulus intervals 
      (ISIs) are often employed to investigate certain neural or psychological 
      phenomena. At short ISIs, however, the ERP responses to successive stimuli may 
      overlap, thereby distorting the ERP averages. This paper describes a signal 
      processing approach for analyzing the distortion of ERP averages due to such 
      overlap. In general, the distortion is modeled in terms of mathematical 
      convolutions of the ERP waveform elicited by each type of adjacent stimulus with 
      the corresponding distribution in time of those stimuli relative to the averaging 
      epoch. Using this framework, a number of implications of ERP overlap for 
      experimental design and interpretation are examined, with special emphasis given 
      to selective attention paradigms. It is shown that the possibility of confound 
      due to ERP overlap is widespread in short-ISI experiments, and even the widely 
      used procedure of stimulus randomization does not necessarily control for 
      differential distortion of the ERPs to attended versus unattended stimuli. 
      Problems due to ERP overlap can be particularly serious in short-ISI studies that 
      examine how ERPs (and associated perceptual processes) are influenced by the 
      nature of the preceding stimulus (i.e., stimulus sequence effects). A set of 
      algorithms is presented for estimating and removing the residual distortion due 
      to response overlap from recorded ERP averages. The use of these algorithms, 
      collectively termed the Adjacent Response (Adjar) Technique, can alleviate many 
      of the overlap-related problems that arise when short ISIs are used, thereby 
      enhancing the power of the ERP technique.
FAU - Woldorff, M G
AU  - Woldorff MG
AD  - Department of Neurosciences, University of California-San Diego, La Jolla.
LA  - eng
GR  - NIMH MH 25594/MH/NIMH NIH HHS/United States
GR  - NINCAS NS 17778/NS/NINDS NIH HHS/United States
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PT  - Research Support, U.S. Gov't, Non-P.H.S.
PT  - Research Support, U.S. Gov't, P.H.S.
PL  - United States
TA  - Psychophysiology
JT  - Psychophysiology
JID - 0142657
SB  - IM
MH  - *Algorithms
MH  - Arousal/*physiology
MH  - Artifacts
MH  - Attention/*physiology
MH  - Cerebral Cortex/physiology
MH  - Dominance, Cerebral/physiology
MH  - Electroencephalography/*instrumentation
MH  - Evoked Potentials, Auditory/physiology
MH  - Humans
MH  - Pitch Discrimination/physiology
MH  - Signal Processing, Computer-Assisted/*instrumentation
EDAT- 1993/01/01 00:00
MHDA- 1993/01/01 00:01
CRDT- 1993/01/01 00:00
PHST- 1993/01/01 00:00 [pubmed]
PHST- 1993/01/01 00:01 [medline]
PHST- 1993/01/01 00:00 [entrez]
AID - 10.1111/j.1469-8986.1993.tb03209.x [doi]
PST - ppublish
SO  - Psychophysiology. 1993 Jan;30(1):98-119. doi: 10.1111/j.1469-8986.1993.tb03209.x.