16 adult male acute schizophrenics in Jordan, who broadly fit the Type I characterization (i.e., less associated with frontotemporal lobe dysfunctions), and 16 matched controls were given a battery of cognitive tests. Patients were impaired on effort-demanding tasks tested by the Wisconsin Card Sorting Test, the Wechsler Adult Intelligence Scale (WAIS), and a verbal fluency test. Patients were not disproportionately impaired on tests of temporal memory or spatial memory or on a rate of forgetting task. It is concluded that the cognitive deficits shown by Type I schizophrenics are caused by a problem in exerting attentional effort of unknown origin.