EFFECTS OF CLOSED-HEAD INJURY ON ATTENTIONAL PROCESSES - GENERALITY OF STERNBERG ADDITIVE FACTOR METHOD

The present study examined the generality of Shum, McFarland, Bain, an d Humphreys' (1990) findings that closed-head injury (CHI) selectively impairs different processes of attention (operationalized in terms of stages of information processing) depending on the severity of, and t he time since, injury. The procedure of Shum et al. was based on Stern berg's additive factor method (AFM), with the mode of information proc essing involved being a physical-directional matching of visual stimul i. The present study followed a similar procedure except that a name-m atching task was used. This task was administered to 16 first-year psy chology students and two groups of CHI patients (viz., severe short-te rm (SS) and severe long-term (SL)) with matched control groups. The re sults obtained replicated the study by Shum in that the SS group was f ound to be impaired on the identification and response-selection stage s of information processing whereas the SL group was found to be impai red only on the response-selection stage. The present study confirms t hat the AFM is not limited to one specific mode of information process and strengthens the validity of the conclusions made by Shum et al. r egarding the effects of CHI on attention.