Here we present the results of the study of the cognitive profile of 11 adult, normally intelligent female fragile X [fra(X)] carriers. In all individuals 3 types of testing were performed: full scale Wechsler Adult Intelligence Scale, a set of neuropsychological tests and an arithmetic achievement test. All 11 subjects showed an average to above-average intelligence but 10 of 11 performed better on the performance than on the verbal subscale. Neuropsychological tests suggest a dysfunction of the reticulo-thalamic axis with deficiency on tests requiring visual memory and a pronounced deficiency of attention skills combined with an impulsive way of completing tests.