title: Distinguishing the influence of task difficulty on error-related ERPs using surface Laplacian transformation.
abstract: Electrophysiologically, errors are characterized by a negative deflection, the error related negativity (ERN), which is followed by the error positivity (Pe). However, it has been suggested that this latter component consists of two subcomponents, with an early frontocentral Pe reflecting a continuation of the ERN, and a centro-parietal Pe reflecting error awareness. Using Laplacian transformed averages, a correct-related negativity (CRN; similar to the ERN), can be found on correct trials. As this technique allows for the decomposition of the recorded scalp potentials resulting in a better dissociation of the underlying brain activities, Laplacian transformation was used in the present study to differentiate between both the ERN/CRN and both Pe components. Additionally, task difficulty was manipulated. Our results show a clearly distinguishable early and late Pe. Both the ERN/CRN and the early Pe varied with task difficulty, showing decreased ERN/early Pe in the difficult condition. However, the late Pe was not influenced by our difficulty manipulation. This suggests that the early and the late Pe reflect qualitatively different processes.
authors.affiliation: Department of Experimental Psychology, Ghent University, Belgium.
authors.forename: Liesbet
authors.initials: L
authors.lastname: Van der Borght
authors.affiliation: Department of Experimental Psychology, Ghent University, Belgium.
authors.forename: Femke
authors.initials: F
authors.lastname: Houtman
authors.affiliation: Laboratoire de Neurosciences Cognitives, UMR7291, Aix-Marseille Université, CNRS, Marseille, France.
authors.forename: Boris
authors.initials: B
authors.lastname: Burle
authors.affiliation: Department of Experimental Psychology, Ghent University, Belgium. Electronic address: wim.notebaert@ugent.be.
authors.forename: Wim
authors.initials: W
authors.lastname: Notebaert
mesh_terms: D000328:Adult; D001288:Attention / Q000502:physiology*; D001364:Awareness / Q000502:physiology; D002540:Cerebral Cortex / Q000502:physiology; D004192:Discrimination, Psychological / Q000502:physiology*; D004569:Electroencephalography / Q000379:methods*; D005071:Evoked Potentials / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D009949:Orientation / Q000502:physiology*; D010364:Pattern Recognition, Visual / Q000502:physiology*; D011338:Probability Theory; D011930:Reaction Time / Q000502:physiology*; D055815:Young Adult
keywords: Error processing; Error-related negativity (ERN); Error-related positivity (Pe); Laplacian transformation; Task difficulty