title: Effects of closed-head injury on attentional processes: an information-processing stage analysis.
abstract: The present study, based on Sternberg's (1969) additive-factor method, examined attentional processes in terms of four information-processing stages (feature extraction, identification, response selection, and motor adjustment). Four task variables were used to operationally define the stages (signal quality, signal similarity, signal-response compatibility, and foreperiod uncertainty). In two studies, a visuo-spatial reaction-time task was undertaken by a group of university subjects (Experiment 1) and by three groups of closed-head-injured patients (severe short-term, severe long-term, and mild short-term) and their corresponding matched controls (Experiment 2). The results indicated that both patients and normals exhibited a similar mode of linear information processing. In addition, it was found that the severe short-term group was impaired on the response-selection stage and response selection stage; the severe long-term group was impaired only on the response-selection; and no evidence of impairment was found for the mild short-term patients. The implications of these findings with reference to the study of attentional processes in closed-head injured patients and to neuropsychological assessment and rehabilitation are discussed.
authors.affiliation: University of Queensland, St. Lucia, Australia.
authors.forename: D H
authors.initials: DH
authors.lastname: Shum
authors.forename: K
authors.initials: K
authors.lastname: McFarland
authors.forename: J D
authors.initials: JD
authors.lastname: Bain
authors.forename: M S
authors.initials: MS
authors.lastname: Humphreys
mesh_terms: D000293:Adolescent; D000328:Adult; D001288:Attention; D001924:Brain Concussion / Q000523:psychology*; D001925:Brain Damage, Chronic / Q000523:psychology*; D002755:Choice Behavior; D004193:Discrimination Learning; D004292:Dominance, Cerebral; D005260:Female; D015600:Glasgow Coma Scale; D006801:Humans; D008297:Male; D009483:Neuropsychological Tests; D009949:Orientation; D010364:Pattern Recognition, Visual; D011597:Psychomotor Performance; D011930:Reaction Time