The attentional blink reveals sluggish attentional shifting in adolescents with specific language impairment

Rapid processing deficits have been the subject of much debate in the literature on specific language impairment (SLI). Hari and Renvall (2001) [Hari, R. & Renvall, H. (2001). Impaired processing of rapid stimulus sequences in dyslexia. Trends in cognitive sciences, 5, 525-532.] proposed that the source of this deficit can be attributed to sluggish attentional shifting abilities. That is, more time is required to shift attention between stimuli. To test this claim, 26 adolescents with SLI (divided into two subgroups to control for differences in non-verbal intelligence) and 14 controls were presented with a rapid serial visual presentation task. In this task participants were asked to detect two visual targets presented serially with distracter items with varying inter-target intervals (i.e., time difference between targets). This task was designed to elicit an attentional blink (AB). The AB describes the phenomenon whereby non-impaired individuals are less likely to report the second of two targets presented within 200-500ms of each other. After controlling for group differences in non-verbal intelligence, the SLI group was found to be significantly less accurate than the control group at successfully reporting the second target at inter-target intervals of 100, 200, 300, 400 and 800ms. The results were interpreted to suggest that adolescents with language impairments have an AB which differs from non-impaired individuals in both magnitude and duration.