How 'generalized' is the 'slowed processing' in SLI? The case of visuospatial attentional orienting.

The study was designed to assess the speed and efficiency of visuospatial attentional orienting and the speed of visual processing and motor response in school-age children diagnosed with specific language impairment (SLI). Fifteen participants with SLI (7-15 years old) and their gender- and age-matched normally developing peers performed two formats of a simple visual discrimination task, one requiring the use of attentional orienting for accurate performance, and the other not requiring shifts of attention. The SLI group was characterized by (a) slower visual processing, and (b) slower motor response, but (c) similar attentional orienting speed, relative to the control group. The results are discussed in relation to the 'generalized slowing hypothesis' in SLI and the neural underpinning of visuospatial attentional orienting and SLI.