Electroencephalography (EEG) and Event‐Related Potentials (ERPs) with Human Participants

Gregory A. Light1, Lisa E. Williams2, Falk Minow3, Joyce Sprock1, Anthony Rissling1, Richard Sharp1, Neal R. Swerdlow1, David L. Braff1

1 Department of Psychiatry, University of California, San Diego, La Jolla, California, 2 Department of Psychology, University of California, San Diego, La Jolla, California, 3 Easycap, Herrsching‐Breitbrunn, Germany
Publication Name:  Current Protocols in Neuroscience
Unit Number:  Unit 6.25
DOI:  10.1002/0471142301.ns0625s52
Online Posting Date:  July, 2010
GO TO THE FULL TEXT: PDF or HTML at Wiley Online Library


Understanding the basic neural processes that underlie complex higher‐order cognitive operations and functional domains is a fundamental goal of cognitive neuroscience. Electroencephalography (EEG) is a non‐invasive and relatively inexpensive method for assessing neurophysiological function that can be used to achieve this goal. EEG measures the electrical activity of large, synchronously firing populations of neurons in the brain with electrodes placed on the scalp. This unit outlines the basics of setting up an EEG experiment with human participants, including equipment, and a step‐by‐step guide to applying and preparing an electrode cap. Also included are support protocols for two event‐related potential (ERP) paradigms, P50 suppression, and mismatch negativity (MMN), which are measures of early sensory processing. These paradigms can be used to assess the integrity of early sensory processing in normal individuals and clinical populations, such as individuals with schizophrenia. Curr. Protoc. Neurosci. 52:6.25.1‐6.25.24. © 2010 by John Wiley & Sons, Inc.

Keywords: electroencephalography (EEG); sensory gating; P50 suppression; mismatch negativity (MMN); schizophrenia

PDF or HTML at Wiley Online Library

Table of Contents

  • Introduction
  • Basic Protocol 1: Preparation of Human Subjects for EEG Studies
  • Alternate Protocol 1: P50 Suppression, a Measure of Sensory Gating
  • Alternate Protocol 2: Mismatch Negativity (MMN), a Measure of Early Auditory Change Detection
  • Commentary
  • Literature Cited
  • Figures
PDF or HTML at Wiley Online Library


Basic Protocol 1: Preparation of Human Subjects for EEG Studies

  • Human participants: if possible, participants should arrive with their hair washed without using additives like conditioner or hair styling products, as this helps significantly to achieve low impedances essential to EEG recording
  • Abrasive electrolyte gel (Abralyt or equivalent)
  • Mild detergent (e.g., children's shampoo)
  • Distilled water
  • Barbicide disinfectant solution
  • Electrically sheltered room/chamber (if available, suggested but not required)
  • Gauss meter with sensitivity to electrical frequency for your location (usually 50 to 60 Hz; e.g., EMF, Allied Products, or equivalent)
  • EEG acquisition software (e.g., Neuroscan, BioSemi, or equivalent)
  • Digital EEG amplifier (e.g., Neuroscan NuAmps, BioSemi, or equivalent)
  • Two computers (see EEG acquisition program documentation for system requirements)
  • Stimulus generator (e.g., EMG‐SR/SR‐HLAB System Stimulus Module or equivalent)
  • Stimulus generation software (e.g., E‐Prime, Presentation, or equivalent)
  • Electrode cap (Easycap or equivalent)
  • Flexible tape measure
  • Ten electrode adaptors of appropriate size for electrodes (e.g., Easycap)
  • Forty (more if high‐density recording is desired) Ag/AgCl sintered ring electrodes (e.g, Easycap)
  • Several cotton swabs with a free wooden end
  • Electrode washers of appropriate size for electrodes (e.g., Easycap)
  • 20‐ml customary syringes (without needle)
  • Electrode tester (UFI Checktrode or equivalent)
  • Foam insert earphones (E.A.R or equivalent; 3M), optional
  • Tissues or towel
  • Towel or cape to cover participant's clothes
  • Facilities and supplies for participants to wash hair after experiment: large sink, spray attachment for faucet, shampoo, conditioner, combs, towels, hair dryer, hand mirror (recommended but not required; participants can wash hair at home if not available)
  • Toothbrush

Alternate Protocol 1: P50 Suppression, a Measure of Sensory Gating

  • Program to deliver clicks as detailed above (this can be programmed in SDI, in the EEG acquisition program, or an external program such as E‐Prime; Psychology Software Tools)
  • Additional reagents and equipment for use of stand‐alone P50 recording and analysis system, LEA2000 (Olincy et al., in press)

Alternate Protocol 2: Mismatch Negativity (MMN), a Measure of Early Auditory Change Detection

  • Program to present standard and deviant stimuli spaced about 500 msec apart (see Additional Materials in protocol 2 for program suggestions)
  • Computer or TV screen to present distracter task; specific equipment needed depends on task employed
PDF or HTML at Wiley Online Library



Literature Cited

Literature Cited
   Adler, L.E., Pachtman, E., Franks, R.D., Pecevich, M., Waldo, M.C., and Freedman, R. 1982a. Neurophysiological evidence for a defect in neuronal mechanisms involved in sensory gating in schizophrenia. Biol. Psychiatry 17:639‐654.
   Adler, L.E., Pachtman, E., Franks, R.D., Pecevich, M., Waldo, M.C., and Freedman, R. 1982b. Neurophysiological evidence for a defect in neuronal mechanisms involved in sensory gating in schizophrenia. Biol. Psychiatry 17:639‐654.
   Baldeweg, T., Klugman, A., Gruzelier, J., and Hirsch, S.R. 2004. Mismatch negativity potentials and cognitive impairment in schizophrenia. Schizophr. Res. 69:203‐217.
   Boutros, N.N., Zouridakis, G., and Overall, J. 1991. Replication and extension of P50 findings in schizophrenia. Clin. Electroencephalogr. 22:40‐45.
   Braff, D.L. and Light, G.A. 2004. Preattentional and attentional cognitive deficits as targets for treating schizophrenia. Psychopharmacology 174:75‐85.
   Braff, D.L. and Light, G.A. 2005. The use of neurophysiological endophenotypes to understand the genetic basis of schizophrenia. Dialogues Clin. Neurosci. 7:125‐135.
   Braff, D.L., Greenwood, T.A., Swerdlow, N.R., Light, G.A., and Schork, N.J. 2008. The Investigators of the Consortium on the Genetics of Schizophrenia, 2008. Advances in endophenotyping schizophrenia. World Psychiatry 7:11‐18.
   Cadenhead, K.S., Light, G.A., Shafer, K.M., and Braff, D.L. 2005. P50 suppression in individuals at risk for schizophrenia: The convergence of clinical, familial, and vulnerability marker risk assessment. Biol. Psychiatry 57:1504‐1509.
   Catts, S.V., Shelley, A.M., Ward, P.B., Liebert, B., McConaghy, N., Andrews, S., and Michie, P.T. 1995. Brain potential evidence for an auditory sensory memory deficit in schizophrenia. Am. J. Psychiatry 152:213‐219.
   Cheour‐Luhtanen, M., Alho, K., Sainio, K., Rinne, T., Reinikainen, K., Pohjavuori, M., Renlund, M., Aaltonen, O., Eerola, O., and Naatanen, R. 1996. The ontogenetically earliest discriminative response of the human brain. Psychophysiology 33:478‐481.
   Clementz, B.A., Geyer, M.A., and Braff, D.L. 1998a. Multiple site evaluation of P50 suppression among schizophrenia and normal comparison subjects. Schizophr. Res. 30:71‐80.
   Clementz, B.A., Geyer, M.A., and Braff, D.L. 1998b. Poor P50 suppression among schizophrenia patients and their 1st degree biological relatives. Am. J. Psych. 155:1691‐1694.
   Dien, J., Spencer, K.M., and Donchin, E. 2004. Parsing the late positive complex: mental chronometry and the ERP components that inhabit the neighborhood of the P300. Psychophysiology 41:665‐678.
   Fischer, C., Morlet, D., Bouchet, P., Luaute, J., Jourdan, C., and Salord, F. 1999. Mismatch negativity and late auditory evoked potentials in comatose patients. Clin. Neurophysiol. 110:1601‐1610.
   Freedman, R., Coon, H., Myles‐Worsley, M., Orr‐Urtreger, A., Olincy, A., Davis, A., Polymeropoulos, M., Holik, J., Hopkins, J., Hoff, M., Rosenthal, J., Waldo, M.C., Reimherr, F., Wender, P., Yaw, J., Young, D.A., Breese, C.R., Adams, C., Patterson, D., Adler, L.E., Kruglyak, L., Leonard, S., and Byerley, W. 1997. Linkage of a neurophysiological deficit in schizophrenia to a chromosome 15 locus. Proc. Natl. Acad. Sci. U.S.A. 94:587‐592.
   Greenwood, T.A., Braff, D.L., Light, G.A., Cadenhead, K.S., Calkins, M.E., Dobie, D.J., Freedman, R., Green, M.F., Gur, R.E., Gur, R.C., Mintz, J., Nuechterlein, K.H., Olincy, A., Radant, A.D., Seidman, L.J., Siever, L.J., Silverman, J.M., Stone, W.S., Swerdlow, N.R., Tsuang, D.W., Tsuang, M.T., Turetsky, B.I., and Schork, N.J. 2007. Initial heritability analyses of endophenotypic measures for schizophrenia: the consortium on the genetics of schizophrenia. Arch. Gen. Psychiatry 64:1242‐1250.
   Griffith, J.M., O'Neill, J.E., Petty, F., Garver, D., Young, D., and Freedman, R. 1998. Nicotinic receptor desensitization and sensory gating deficits in schizophrenia. Biol. Psychiatry 44:98‐106.
   Grillon, C., Courchesne, E., Ameli, R., Geyer, M.A., and Braff, D.L. 1990. Increased distractibility in schizophrenic patients. Electrophysiologic and behavioral evidence. Arch. Gen. Psychiatry 47:171‐179.
   Kawakubo, Y. and Kasai, K. 2006. Support for an association between mismatch negativity and social functioning in schizophrenia. Prog. Neuropsychopharmacol. Biol. Psychiatry 30:1367‐1368.
   Kawakubo, Y., Kasai, K., Kudo, N., Rogers, M.A., Nakagome, K., Itoh, K., and Kato, N. 2006. Phonetic mismatch negativity predicts verbal memory deficits in schizophrenia. Neuroreport 17:1043‐1046.
   Kawakubo, Y., Kamio, S., Nose, T., Iwanami, A., Nakagome, K., Fukuda, M., Kato, N., Rogers, M.A., and Kasai, K. 2007. Phonetic mismatch negativity predicts social skills acquisition in schizophrenia. Psychiatry Res. 152:261‐265.
   Kiang, M., Braff, D.L., Sprock, J., and Light, G.A. 2009. The relationship between preattentive sensory processing deficits and age in schizophrenia patients. Clin Neurophysiol. 120:1949‐1957.
   Light, G.A. and Braff, D.L. 1998. The “incredible shrinking” P50 event‐related potential. Biol. Psychiatry 43:918‐920.
   Light, G.A. and Braff, D.L. 2001. Measuring P50 suppression and prepulse inhibition in a single recording session. Am. J. Psychiatry 158:2066‐2068.
   Light, G.A. and Braff, D.L. 2005a. Mismatch negativity deficits are associated with poor functioning in schizophrenia patients. Arch. Gen. Psychiatry 62:127‐136.
   Light, G.A. and Braff, D.L. 2005b. Stability of mismatch negativity deficits and their relationship to functional impairments in chronic schizophrenia. Am. J. Psychiatry 162:1741‐1743.
   Light, G.A., Swerdlow, N.R., and Braff, D.L. 2007. Preattentive sensory processing as indexed by the MMN and P3a brain responses is associated with cognitive and psychosocial functioning in healthy adults. J. Cogn. Neurosci. 19:1624‐1632.
   Mathalon, D.H., Ford, J.M., and Pfefferbaum, A. 2000. Trait and state aspects of P300 amplitude reduction in schizophrenia: A retrospective longitudinal study. Biol. Psychiatry 47:434‐449.
   Michie, P.T. 2001. What has MMN revealed about the auditory system in schizophrenia? Int. J. Psychophysiol. 42:177‐194.
   Muller‐Gass, A., Stelmack, R.M., and Campbell, K.B. 2006. The effect of visual task difficulty and attentional direction on the detection of acoustic change as indexed by the Mismatch Negativity. Brain Res. 1078:112‐130.
   Naatanen, R. 1992. Attention and Brain Function. Lawrence Erlbaum Associates, Hillsdale, New Jersey.
   Naatanen, R., Paavilainen, P., Alho, K., Reinikainen, K., and Sams, M. 1989. Do event‐related potentials reveal the mechanism of the auditory sensory memory in the human brain? Neurosci. Lett. 98:217‐221.
   Naatanen, R., Tervaniemi, M., Sussman, E., Paavilainen, P., and Winkler, I. 2001. “Primitive intelligence” in the auditory cortex. Trends Neurosci. 24:283‐288.
   Nashida, T., Yabe, H., Sato, Y., Hiruma, T., Sutoh, T., Shinozaki, N., and Kaneko, S. 2000. Automatic auditory information processing in sleep. Sleep 23:821‐828.
   Nunez, P.L. and Srinivasan, R. 2006. Electric Fields of the Brain: The Neurophysics of EEG, 2nd ed. Oxford University Press, New York.
   Oades, R.D., Dittmann‐Balcar, A., Zerbin, D., and Grzella, I. 1997. Impaired attention‐dependent augmentation of MMN in nonparanoid vs paranoid schizophrenic patients: A comparison with obsessive‐compulsive disorder and healthy subjects. Biol. Psychiatry 41:1196‐1210.
   Olincy, A., Braff, D.L., Adler, L.E., Cadenhead, K.S., Calkins, M.E., Dobie, D.J., Green, M.F., Greenwood, T.A., Gur, R.E., Gur, R.C., Light, G.A., Mintz, J., Nuechterlein, K.H., Radant, A.D., Schork, N.J., Seidman, L.J., Siever, L.J., Silverman, J.M., Stone, W.S., Swerdlow, N.R., Tsuang, D.W., Tsuang, M.T., Turetsky, B.I., Wagner, B.D., and Freedman, R. 2010. Inhibition of the P50 cerebral evoked response to repeated auditory stimuli: Results from the Consortium on Genetics of Schizophrenia. Schizophr. Res. In press.
   Pekkonen, E., Rinne, T., and Naatanen, R. 1995. Variability and replicability of the mismatch negativity. Electroencephalogr. Clin. Neurophysiol. 96:546‐554.
   Polich, J. and Criado, J.R. 2006. Neuropsychology and neuropharmacology of P3a and P3b. Int. J. Psychophysiol. 60:172‐185.
   Rentzsch, J., Jockers‐Scherubl, M.C., Boutros, N.N., and Gallinat, J. 2008. Test‐retest reliability of P50, N100 and P200 auditory sensory gating in healthy subjects. Int. J. Psychophysiol. 67:81‐90.
   Rinne, T., Antila, S., and Winkler, I. 2001. Mismatch negativity is unaffected by top‐down predictive information. Neuroreport 12:2209‐2213.
   Sams, M., Hamalainen, M., Antervo, A., Kaukoranta, E., Reinikainen, K., and Hari, R. 1985. Cerebral neuromagnetic responses evoked by short auditory stimuli. Electroencephalogr. Clin. Neurophysiol. 61:254‐266.
   Squires, N.K., Squires, K.C., and Hillyard, S.A. 1975. Two varieties of long‐latency positive waves evoked by unpredictable auditory stimuli in man. Electroencephalogr. Clin. Neurophysiol. 38:387‐401.
   Sussman, E., Winkler, I., and Wang, W. 2003. MMN and attention: Competition for deviance detection. Psychophysiology 40:430‐435.
   Swerdlow, N.R., Geyer, M.A., Shoemaker, J.M., Light, G.A., Braff, D.L., Stevens, K.E., Sharp, R., Breier, M., Neary, A., and Auerbach, P.P. 2006. Convergence and divergence in the neurochemical regulation of prepulse inhibition of startle and N40 suppression in rats. Neuropsychopharmacology 31:506‐515.
   Tiitinen, H., May, P., Reinikainen, K., and Naatanen, R. 1994. Attentive novelty detection in humans is governed by pre‐attentive sensory memory. Nature 372:90‐92.
   Turetsky, B., Colbath, E.A., and Gur, R.E. 1998. P300 subcomponent abnormalities in schizophrenia: II. Longitudinal stability and relationship to symptom change. Biol. Psychiatry 43:31‐39.
   Turetsky, B.I., Calkins, M.E., Light, G.A., Olincy, A., Radant, A.D., and Swerdlow, N.R. 2007. Neurophysiological endophenotypes of schizophrenia: The viability of selected candidate measures. Schizophr. Bull. 33:69‐94.
   Umbricht, D. and Krljes, S. 2005. Mismatch negativity in schizophrenia: a meta‐analysis. Schizophr. Res. 76:1‐23.
   Woods, D.L., Alho, K., and Algazi, A. 1992. Intermodal selective attention. I. Effects on event‐related potentials to lateralized auditory and visual stimuli. Electroencephalogr. Clin. Neurophysiol. 82:341‐355.
PDF or HTML at Wiley Online Library