The main goal of this study was to examine the performance on frontal lobe tests of normal adolescent subjects and subjects psychometrically denned as schizotypics using double criteria: (1) a CPT- linked attention deficit vulnerability and (2) a psychosis proneness measured with the Chapman's perceptual aberration scale (PAS) and the social anhedonia scale (SAS). Frontal lobe performance was assessed with the Wisconsin card sorting test (WCST), the trail-making test (TMT) and a word generation test. Overall, results show that subjects with both a CPT-linked vulnerability and a psychosis proneness did worse than the rest of subjects in most frontal lobe tests, suggesting the existence of a subtle frontal-lobe dysfunction in 'normal' adolescents that are at increased risk for schizophrenia. Our results agree with current theories that hypothesize a possible frontal-limbic dysfunction latent in schizophrenia spectrum disorders. The importance of an accurate definition of schizotypy, the specificity of the instruments and new approaches to the study of schizotypy are discussed. © 1997 Elsevier Science Ltd.