Top

Published in:

Open Access 01-07-2019 | Review

Which Reference Should We Use for EEG and ERP practice?

Authors: Dezhong Yao, Yun Qin, Shiang Hu, Li Dong, Maria L. Bringas Vega, Pedro A. Valdés Sosa

Published in: Brain Topography | Issue 4/2019

Abstract

Which reference is appropriate for the scalp ERP and EEG studies? This unsettled problem still inspires unceasing debate. The ideal reference should be the one with zero or constant potential but unfortunately it is well known that no point on the body fulfills this condition. Consequently, more than ten references are used in the present EEG-ERP studies. This diversity seriously undermines the reproducibility and comparability of results across laboratories. A comprehensive review accompanied by a brief communication with rigorous derivations and notable properties (Hu et al. Brain Topogr, 2019. https://doi.org/10.1007/s10548-019-00706-y) is thus necessary to provide application-oriented principled recommendations. In this paper current popular references are classified into two categories: (1) unipolar references that construct a neutral reference, including both online unipolar references and offline re-references. Examples of unipolar references are the reference electrode standardization technique (REST), average reference (AR), and linked-mastoids/ears reference (LM); (2) non-unipolar references that include the bipolar reference and the Laplacian reference. We show that each reference is derived with a different assumption and serves different aims. We also note from (Hu et al. 2019) that there is a general form for the reference problem, the ‘no memory’ property of the unipolar references, and a unified estimator for the potentials at infinity termed as the regularized REST (rREST) which has more advantageous statistical evidence than AR. A thorough discussion of the advantages and limitations of references is provided with recommendations in the hope to clarify the role of each reference in the ERP and EEG practice.

Babiloni F, Cincotti F, Carducci F et al (2001) Spatial enhancement of EEG data by surface Laplacian estimation: the use of magnetic resonance imaging-based head models. Clin Neurophysiol 112:724–727. https://doi.org/10.1016/s1388-2457(01)00494-1 CrossRefPubMed

Babiloni C, Klimesch W, Drinkenburg WHIM et al (2019) International Federation of Clinical Neurophysiology (IFCN) Guidelines for topographic and frequency analysis of resting state electroencephalographic rhythms. Clin Neurophysiol 129:e208CrossRef

Berger H (1929) Uber das Elektrenkephalogramm des Menschen. Arch Psychiat Nervenkr 87:527–570CrossRef

Bertrand O, Perrin F, Pernier J (1985) A theoretical justification of the average reference in topographic evoked potential studies. Electroencephalogr Clin Neurophysiol 62:462–464CrossRefPubMed

Besio W, Koka K, Patwardhan R (2004) Computer simulation and tank experimental verification of concentric ring electrodes. In: Proceedings of the 26th annual international conference of IEEE engineering in medicine and biology society. 1–7(26):2243–2246

Besio WG, Koka K, Aakula R, Dai WZ (2006) Tri-polar concentric ring electrode development for Laplacian electroencephalography. IEEE Trans Biomed Eng 53:926–933. https://doi.org/10.1109/tbme.2005.863887 CrossRefPubMed

Bonfiglio L, Olcese U, Rossi B et al (2013) Cortical source of blink-related delta oscillations and their correlation with levels of consciousness. Hum Brain Mapp 34:2178–2189. https://doi.org/10.1002/hbm.22056 CrossRefPubMed

Chella F, Pizzella V, Zappasodi F, Marzetti L (2016) Impact of the reference choice on scalp EEG connectivity estimation. J Neural Eng 13:1–21. https://doi.org/10.1088/1741-2560/13/3/036016 CrossRef

Chella F, D’Andrea A, Basti A et al (2017) Non-linear analysis of scalp EEG by using bispectra: the effect of the reference choice. Front Neurosci 11:1–15. https://doi.org/10.3389/fnins.2017.00262 CrossRef

Dampney CNG (1969) The equivalent source techniqe. Geophysics 34:539–553CrossRef

Dong L, Li F, Liu Q et al (2017) MATLAB toolboxes for reference electrode standardization technique (REST) of Scalp EEG. Front Neurosci. https://doi.org/10.3389/fnins.2017.00601 CrossRefPubMedPubMedCentral

Faux SF, Shenton ME, McCarley RW et al (1990) Preservation of P300 event-related potential topographic asymmetries in schizophrenia with use of either linked-ear or nose reference sites. Electroencephalogr Clin Neurophysiol 75:378–391CrossRefPubMed

Fein G, Raz J, Brown FF, Merrin EL (1988) Common reference coherence data are confounded by power and phase effects. Electroencephalogr Clin Neurophysiol 69:581–584. https://doi.org/10.1016/0013-4694(88)90171-x CrossRefPubMed

Feindel W, Leblanc R, de Almeida AN (2009) Epilepsy surgery: historical highlights 1909-2009. Epilepsia 50(Suppl 3):131–151. https://doi.org/10.1111/j.1528-1167.2009.02043.x CrossRefPubMed

Giard MH, Besle J, Aguera PE et al (2014) Scalp current density mapping in the analysis of mismatch negativity paradigms. Brain Topogr 27:428–437. https://doi.org/10.1007/s10548-013-0324-8 CrossRefPubMed

Gibbs FA, Davis H, Lennox WG (1935) The electro-encephalogram in epilepsy and in conditions of impaired consciousness. Arch Neurol Psychiatry 34:1133–1148CrossRef

Gibbs FA, Lennox WG, Gibbs EL (1936) The electroencephalogram in diagnosis and in localization of epileptic seizures. Annee Psychol 36:1225–1235

Gloor P (1969) Hans Berger on electroencephalography. Am J EEG Technol 9:1–8CrossRef

Goldman D (1950) The clinical use of the “average” reference electrode in monopolar recording. Electroencephalogr Clin Neurophysiol 2:209–212. https://doi.org/10.1016/0013-4694(50)90039-3 CrossRefPubMed

Gulrajani RM (1998) Bioelectricity and biomagnetism. John Wiley & Sons, New York

Hernandez-Gonzalez G, Bringas-Vega ML, Galán-Garcia L et al (2011) Multimodal quantitative neuroimaging databases and methods: the Cuban human brain mapping project. Clin EEG Neurosci 42:149–159. https://doi.org/10.1177/155005941104200303 CrossRefPubMed

Hjorth B (1975) An on-line transformation of EEG scalp potentials into orthogonal source derivations. Electroencephalogr Clin Neurophysiol 39:526–530. https://doi.org/10.1016/0013-4694(75)90056-5 CrossRefPubMed

Hu S, Karahan E, Valdes-Sosa PA (2018a) Restate the reference for EEG microstate analysis. arXiv:1802.02701

Hu S, Lai Y, Valdes-Sosa PA et al (2018b) How do reference montage and electrodes setup affect the measured scalp EEG potentials? J Neural Eng 15:026013. https://doi.org/10.1088/1741-2552/aaa13f CrossRefPubMed

Hu S, Yao D, Valdes-Sosa PA (2018c) Unified Bayesian estimator of EEG reference at infinity: rREST (regularized reference electrode standardization technique). Front Neurosci. https://doi.org/10.3389/fnins.2018.00297 CrossRefPubMedPubMedCentral

Hu S, Yao D, Bringas-Vega ML et al (2019) The statistics of EEG unipolar references: derivations and properties. Brain Topogr. https://doi.org/10.1007/s10548-019-00706-y CrossRefPubMedPubMedCentral

Huang Y, Zhang J, Cui Y et al (2017) How different EEG references influence sensor level functional connectivity graphs. Front Neurosci 11:1–12. https://doi.org/10.3389/fnins.2017.00368 CrossRef

Huang XL, Long ZL, Lei X (2018) Electrophysiological signatures of the resting-state fMRI global signal: a simultaneous EEG-fMRI study. J Neurosci Methods 311:351–359CrossRefPubMed

Konishi S, Kitagawa G (2008) Information criteria and statistical modeling. Springer, New YorkCrossRef

Kugiumtzis D, Kimiskidis VK (2015) Direct causal networks for the study of transcranial magnetic stimulation effects on focal epileptiform discharges. Int J Neural Syst. https://doi.org/10.1142/s0129065715500069 CrossRefPubMed

La Vaque TJ (1999) The History of EEG Hans Berger. J Neurother 3:1–9CrossRef

Lai YX, Yao DZ (2009) Local Laplacian estimate on spherical head surface. Chinese J Electron 18(681):685

Li FL, Chen B, Li H et al (2016) The time-varying networks in P300: A task-evoked EEG study. IEEE Trans Neural Syst Rehabil Eng 24:725–733. https://doi.org/10.1109/tnsre.2016.2523678 CrossRefPubMed

Liu Q, Balsters JH, Baechinger M et al (2015) Estimating a neutral reference for electroencephalographic recordings: the importance of using a high-density montage and a realistic head model. J Neural Eng 12:056012. https://doi.org/10.1088/1741-2560/12/5/056012 CrossRefPubMedPubMedCentral

Luck SJ (2014) An introduction to the event-related potential technique. Second, Massachusetts Institute of Technology

Malmivuo J, Plonsey R (1995) Bioelectromagnetism: principles and applications of bioelectric and biomagnetic fields. Oxford University, New YorkCrossRef

Marzetti L, Nolte G, Perrucci MG et al (2007) The use of standardized infinity reference in EEG coherency studies. Neuroimage 36:48–63. https://doi.org/10.1016/j.neuroimage.2007.02.034 CrossRefPubMed

Mumtaz W, Malik AS (2018) A comparative study of different EEG reference choices for diagnosing unipolar depression. Brain Topogr 31:875–885. https://doi.org/10.1007/s10548-018-0651-x CrossRefPubMed

Niedermeyer E (1987) The normal EEG of the waking adult. In: Niedermeyer E, Lopes da Silva F (eds) Electroencephalography. Urban and Schwarzenberg, Baltimore

Niedermeyer E, Da Silva F (2005) Electroencephalography: basic principles, clinical applications and related fields, 5th edn. Lippincott Williams & Wilkins, Philadelphia

Nunez PL (2010) REST: A good idea but not the gold standard. Clin Neurophysiol 121:2177–2180. https://doi.org/10.1016/j.clinph.2010.04.029 CrossRefPubMedPubMedCentral

Nunez PL, Srinivasan R (2006) Electric fields of the brain: the neurophysics of EEG, 2nd edn. Oxford University Press, OxfordCrossRef

Offner FF (1950) The EEG as potential mapping: the value of the average monopolar reference. Electroencephalogr Clin Neurophysiol 2:213–214. https://doi.org/10.1016/0013-4694(50)90040-x CrossRefPubMed

Pascual-Marqui RD, Lehmann D (1993) Topographic maps, source localization inference, and the reference electrode—comments. Electroencephalogr Clin Neurophysiol 88:532–533. https://doi.org/10.1016/0168-5597(93)90043-o CrossRefPubMed

Pascual-marqui RD, Gonzalez-andino SL, Valdes-sosa PA (1988) Current source density estimation and interpolation based on the spherical harmonic Fourier expansion. Int J Neurosci 43:237–249. https://doi.org/10.3109/00207458808986175 CrossRefPubMed

Pascual-Marqui RD, Michel CM, Lehmann D (1994) Low resolution electromagnetic tomography: a new method for localizing electrical activity in the brain. Int J Psychophysiol 18:49–65CrossRefPubMed

Perrin FJ, Pernier J, Bertrand O, Echallier JF (1989) Errata corrige on: Spherical spline for potential and current density mapping. Electroencephalogr Clin Neurophysiol 72:184–187CrossRefPubMed

Plonsey R, Heppner DB (1967) Considerations of quasi-stationarity in electrophysiological systems. Bull Math Biophys 29:657–664CrossRefPubMed

Qin Y, Xu P, Yao D (2010) A comparative study of different references for EEG default mode network: the use of the infinity reference. Clin Neurophysiol 121:1981–1991. https://doi.org/10.1016/j.clinph.2010.03.056 CrossRefPubMed

Qin Y, Xin XW, Zhu H et al (2017) A comparative study on the dynamic EEG center of mass with different references. Front Neurosci. https://doi.org/10.3389/fnins.2017.00509 CrossRefPubMedPubMedCentral

Reilly EL (2005) EEG recording and operation of the apparatus. In: Niedermeyer E, Da Silva FL (eds) Electroencephalography: basic principles, clinical applications, and related fields, 5th edn. Lippincott, Williams and Wilkins, Philadelphia, pp 139–159

Robert Christian P (2007) The Bayesian choice. Springer, New York

Shaw JC (1984) Correlation and coherence analysis of the EEG: a selective tutorial review. Int J Psychophysiol 1:255–266. https://doi.org/10.1016/0167-8760(84)90045-x CrossRefPubMed

Stone JL, Hughes JR (2013) Early history of electroencephalography and establishment of the American Clinical Neurophysiology Society. J Clin Neurophysiol 30:28–44. https://doi.org/10.1097/wnp.0b013e31827edb2d CrossRefPubMed

Tenke CE, Kayser J (2005) Reference-free quantification of EEG spectra: combining current source density (CSD) and frequency principal components analysis (fPCA). Clin Neurophysiol 116:2826–2846. https://doi.org/10.1016/j.clinph.2005.08.007 CrossRefPubMed

Tian Y, Yao DZ (2013) Why do we need to use a zero reference? Reference influences on the ERPs of audiovisual effects. Psychophysiology 50:1282–1290. https://doi.org/10.1111/psyp.12130 CrossRefPubMed

Tian Y, Xu W, Zhang H et al (2017) The scalp time-varying networks of N170: reference, latency and information flow. Front Neurosci 2018:250. https://doi.org/10.3389/fnins.2018.00250 CrossRef

Travis F (1994) A second linked-reference issue: possible biasing of power and coherence spectra. Int J Neurosci 75:111–117CrossRefPubMed

Vorwerk J, Oostenveld R, Piastra MC et al (2018) The FieldTrip-SimBio pipeline for EEG forward solutions. Biomed Eng Online 17:37. https://doi.org/10.1186/s12938-018-0463-y CrossRefPubMedPubMedCentral

Xu P, Xiong XC, Xue Q et al (2014) Recognizing mild cognitive impairment based on network connectivity analysis of resting EEG with zero reference. Physiol Meas 35:1279–1298. https://doi.org/10.1088/0967-3334/35/7/1279 CrossRefPubMed

Yan Y, Nunez PL, Hart RT (1991) Finite-element model of the human head–scalp potentials due to dipole sources. Med Biol Eng Comput 29:475–481CrossRefPubMed

Yao DZ (2000a) Electric potential produced by a dipole in a homogeneous conducting sphere. IEEE Trans Biomed Eng 47:964–966. https://doi.org/10.1109/10.846691 CrossRefPubMed

Yao DZ (2000b) High-resolution EEG mappings: a spherical harmonic spectra theory and simulation results. Clin Neurophysiol 111:81–92CrossRef

Yao D (2001) A method to standardize a reference of scalp EEG recordings to a point at infinity. Physiol Meas 22:693–711. https://doi.org/10.1088/0967-3334/22/4/305 CrossRefPubMed

Yao DZ (2002a) The theoretical relation of scalp Laplacian and scalp current density of a spherical shell head model. Phys Med Biol 47:2179–2185. https://doi.org/10.1088/0031-9155/47/12/312 CrossRefPubMed

Yao DZ (2002b) High-resolution EEG mapping: a radial-basis function based approach to the scalp Laplacian estimate. Clin Neurophysiol 113:956–967. https://doi.org/10.1016/s1388-2457(02)00053-6 CrossRefPubMed

Yao D (2017) Is the surface potential integral of a dipole in a volume conductor always zero? A cloud over the average reference of EEG and ERP. Brain Topogr 30:161–171. https://doi.org/10.1007/s10548-016-0543-x CrossRefPubMedPubMedCentral

Yao D, He B (1998) The Laplacian weighted minimum norm estimate of three dimensional equivalent charge distribution in the brain. In: Proceedings of the 20th annual international conference of the IEEE engineering in medicine and biology society. Vol. 20 Biomedical Engineering Towards the Year 2000 and Beyond (Cat. No.98CH36286). IEEE, pp 2108–2111

Yao D, He B (2003) Equivalent physical models and formulation of equivalent source layer in high-resolution EEG imaging. Phys Med Biol 48:3475–3483. https://doi.org/10.1088/0031-9155/48/21/002 CrossRefPubMed

Yao DZ, Wang L, Oostenveld R et al (2005) A comparative study of different references for EEG spectral mapping: the issue of the neutral reference and the use of the infinity reference. Physiol Meas 26:173–184. https://doi.org/10.1088/0967-3334/26/3/003 CrossRefPubMed

Zhai Y, Yao D (2004a) A study on the reference electrode standardization technique for a realistic head model. Comput Methods Programs Biomed 76:229–238. https://doi.org/10.1016/j.cmpb.2004.07.002 CrossRefPubMed

Zhai YR, Yao DZ (2004b) A radial-basis function based surface Laplacian estimate for a realistic head model. Brain Topogr 17:55–62. https://doi.org/10.1023/b:brat.0000047337.25591.32 CrossRefPubMed

Title: Which Reference Should We Use for EEG and ERP practice?
Authors: Dezhong Yao
Yun Qin
Shiang Hu
Li Dong
Maria L. Bringas Vega
Pedro A. Valdés Sosa
Publication date: 01-07-2019
Publisher: Springer US
Published in: Brain Topography / Issue 4/2019
Print ISSN: 0896-0267
Electronic ISSN: 1573-6792
DOI: https://doi.org/10.1007/s10548-019-00707-x

At a glance: The STEP trials

Springer Medicine

Which Reference Should We Use for EEG and ERP practice?

Abstract

At a glance: The STEP trials

Springer Medicine

Abstract

Please log in to get access to this content

Other articles of this Issue 4/2019

Intracerebral Sources Reconstructed on the Basis of High-Resolution Scalp EEG and MEG

Validating Non-invasive EEG Source Imaging Using Optimal Electrode Configurations on a Representative Rat Head Model

ERP Source Analysis Guided by fMRI During Familiar Face Processing

Quantifying the Effect of Demixing Approaches on Directed Connectivity Estimated Between Reconstructed EEG Sources

A Comparative Study of the Robustness of Frequency-Domain Connectivity Measures to Finite Data Length

Bayesian Modelling of Induced Responses and Neuronal Rhythms