title: Is comprehension necessary for error detection? A conflict-based account of monitoring in speech production.
abstract: Despite the existence of speech errors, verbal communication is successful because speakers can detect (and correct) their errors. The standard theory of speech-error detection, the perceptual-loop account, posits that the comprehension system monitors production output for errors. Such a comprehension-based monitor, however, cannot explain the double dissociation between comprehension and error-detection ability observed in the aphasic patients. We propose a new theory of speech-error detection which is instead based on the production process itself. The theory borrows from studies of forced-choice-response tasks the notion that error detection is accomplished by monitoring response conflict via a frontal brain structure, such as the anterior cingulate cortex. We adapt this idea to the two-step model of word production, and test the model-derived predictions on a sample of aphasic patients. Our results show a strong correlation between patients' error-detection ability and the model's characterization of their production skills, and no significant correlation between error detection and comprehension measures, thus supporting a production-based monitor, generally, and the implemented conflict-based monitor in particular. The successful application of the conflict-based theory to error-detection in linguistic, as well as non-linguistic domains points to a domain-general monitoring system.
authors.affiliation: Beckman Institute, University of Illinois at Urbana-Champaign, 405 N. Matthews Ave., Urbana, IL 61801, USA. nnozari2@illinois.edu
authors.forename: Nazbanou
authors.initials: N
authors.lastname: Nozari
authors.forename: Gary S
authors.initials: GS
authors.lastname: Dell
authors.forename: Myrna F
authors.initials: MF
authors.lastname: Schwartz
mesh_terms: D000328:Adult; D001037:Aphasia / Q000503:physiopathology*; D032882:Comprehension / Q000502:physiology*; D003198:Computer Simulation; D005260:Female; D006801:Humans; D007802:Language; D008297:Male; D008875:Middle Aged; D008960:Models, Psychological; D013060:Speech / Q000502:physiology*; D013068:Speech Production Measurement