Strengths and weaknesses in the intellectual functioning of males with fragile X syndrome

The intellectual strengths and weaknesses of 14 boys and young men with fragile X syndrome were assessed using the Sequential, Simultaneous, and Achievement domains of the Kaufman Assessment Battery for Children. Sequential processing, auditory, visual and motoric short-term memory, and arithmetic skills emerged as significant areas of weakness. Significant strengths were found in perceptual closure, inference, and flexibility. These findings both extend and contradict previous research and show the importance of classifying research groups by etiology of retardation rather than by overall level of impairment.