title: Left neglect dyslexia: Perseveration and reading error types.
abstract: Right-brain-damaged patients may show a reading disorder termed neglect dyslexia. Patients with left neglect dyslexia omit letters on the left-hand-side (the beginning, when reading left-to-right) part of the letter string, substitute them with other letters, and add letters to the left of the string. The aim of this study was to investigate the pattern of association, if any, between error types in patients with left neglect dyslexia and recurrent perseveration (a productive visuo-motor deficit characterized by addition of marks) in target cancellation. Specifically, we aimed at assessing whether different productive symptoms (relative to the reading and the visuo-motor domains) could be associated in patients with left spatial neglect. Fifty-four right-brain-damaged patients took part in the study: 50 out of the 54 patients showed left spatial neglect, with 27 of them also exhibiting left neglect dyslexia. Neglect dyslexic patients who showed perseveration produced mainly substitution neglect errors in reading. Conversely, omissions were the prevailing reading error pattern in neglect dyslexic patients without perseveration. Addition reading errors were much infrequent. Different functional pathological mechanisms may underlie omission and substitution reading errors committed by right-brain-damaged patients with left neglect dyslexia. One such mechanism, involving the defective stopping of inappropriate responses, may contribute to both recurrent perseveration in target cancellation, and substitution errors in reading. Productive pathological phenomena, together with deficits of spatial attention to events taking place on the left-hand-side of space, shape the manifestations of neglect dyslexia, and, more generally, of spatial neglect.
authors.affiliation: Laboratory of Cognitive Neuroscience, Brain Mind Institute, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne, Campus Biotech H4, Chemin des Mines 9, 1202 Geneva, Switzerland; Neuropsychological Laboratory, S. Luca Hospital, IRCCS Istituto Auxologico Italiano, Via Mercalli 32, 20122 Milano, Italy. Electronic address: roberta.ronchi@epfl.ch.
authors.forename: Roberta
authors.initials: R
authors.lastname: Ronchi
authors.affiliation: Unità di Psicologia Clinica, Ospedale Papa Giovanni XXIII, Piazza OMS 1, 24127 Bergamo, Italy.
authors.forename: Lorella
authors.initials: L
authors.lastname: Algeri
authors.affiliation: Unità di Psicologia Clinica, Ospedale Papa Giovanni XXIII, Piazza OMS 1, 24127 Bergamo, Italy.
authors.forename: Laura
authors.initials: L
authors.lastname: Chiapella
authors.affiliation: Department of Psychology and Milan Centre for Neuroscience, University of Milano-Bicocca, Piazza dell'Ateneo Nuovo 1, 20126 Milano, Italy.
authors.forename: Marcello
authors.initials: M
authors.lastname: Gallucci
authors.affiliation: Unità di Psicologia Clinica, Ospedale Papa Giovanni XXIII, Piazza OMS 1, 24127 Bergamo, Italy.
authors.forename: Maria Simonetta
authors.initials: MS
authors.lastname: Spada
authors.affiliation: Neuropsychological Laboratory, S. Luca Hospital, IRCCS Istituto Auxologico Italiano, Via Mercalli 32, 20122 Milano, Italy; Department of Psychology and Milan Centre for Neuroscience, University of Milano-Bicocca, Piazza dell'Ateneo Nuovo 1, 20126 Milano, Italy. Electronic address: giuseppe.vallar@unimib.it.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Vallar
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001931:Brain Mapping; D002540:Cerebral Cortex / Q000000981:diagnostic imaging / Q000473:pathology*; D004410:Dyslexia / Q000150:complications* / Q000000981:diagnostic imaging; D005260:Female; D007839:Functional Laterality / Q000502:physiology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D010468:Perceptual Disorders / Q000150:complications* / Q000000981:diagnostic imaging; D011597:Psychomotor Performance / Q000502:physiology; D011932:Reading
keywords: Left unilateral spatial neglect; Neglect dyslexia; Omission and substitution reading errors; Recurrent perseveration; Right-brain-damaged patients