title: Reaction-time binning: a simple method for increasing the resolving power of ERP averages.
abstract: Stimulus-locked, response-locked, and ERP-locked averaging are effective methods for reducing artifacts in ERP analysis. However, they suffer from a magnifying-glass effect: they increase the resolution of specific ERPs at the cost of blurring other ERPs. Here we propose an extremely simple technique-binning trials based on response times and then averaging-which can significantly alleviate the problems of other averaging methods. We have empirically evaluated the technique in an experiment where the task requires detecting a target in the presence of distractors. We have also studied the signal-to-noise ratio and the resolving power of averages with and without binning. Results indicate that the method produces clearer representations of ERPs than either stimulus-locked and response-locked averaging, revealing finer details of ERPs and helping in the evaluation of the amplitude and latency of ERP waves. The method is applicable to within-subject and between-subject averages.
authors.affiliation: Brain Computer Interfaces Laboratory, School of Computer Science and Electronic Engineering, University of Essex, Colchester, 304 ESQ, UK. rpoli@essex.ac.uk
authors.forename: Riccardo
authors.initials: R
authors.lastname: Poli
authors.forename: Caterina
authors.initials: C
authors.lastname: Cinel
authors.forename: Luca
authors.initials: L
authors.lastname: Citi
authors.forename: Francisco
authors.initials: F
authors.lastname: Sepulveda
mesh_terms: D000328:Adult; D000465:Algorithms; D016477:Artifacts; D003627:Data Interpretation, Statistical; D004569:Electroencephalography / Q000706:statistics & numerical data*; D005071:Evoked Potentials / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D015233:Models, Statistical; D010775:Photic Stimulation; D011597:Psychomotor Performance / Q000502:physiology; D011930:Reaction Time / Q000502:physiology*; D018401:Sample Size; D055815:Young Adult