Cheng WJ, et al. - Given that high levels of ketamine abuse are associated with persisting psychosis (KPP) in a minority of users, researchers here assessed the cognitive function among KPP patients and whether the cognitive impairments associated with KPP resemble those of schizophrenia (SZ). In this work, the symptom profile and cognitive impairments associated with persisting psychosis due to chronic heavy ketamine abuse were observed to resemble those of schizophrenia. However, nonpsychotic ketamine users showed significantly less severe symptom profile and cognitive impairment than KPP and SZ.