Drs. Duggal and Nizamie use these findings to raise the issue of whether this type of abnormality might reflect a neurobiological component of schizotaxia. More generally, their findings underscore questions about how to define and validate the syndrome. It is clear that research over several decades shows a wide range of clinical, social, neurobiological, and neuropsychological deficits in the first-degree relatives of patients with schizophrenia. Nevertheless, while these features may resemble those that occur in schizophrenia, and may even differ significantly from those of normal comparison subjects, they are not all necessarily good candidates for use as diagnostic criteria (2). This is true, for example, if performance variability on a particular measure precludes useful estimates of sensitivity or specificity. In fact, Drs. Duggal and Nizamie make a similar point when they describe how negative symptoms may occur in unrelated clinical conditions. This highlights the need for field trials to determine the utility of including particular symptoms as diagnostic criteria in schizotaxic syndrome.