Manifestation of Psychosis and Impairments of Executive Functions Emphasize the Interaction of Psychological and Neurological Dysfunctions in People Who Use Methamphetamine

Aim: Cumulative evidence has demonstrated the neurotoxic effect of methamphetamine (Meth) on the central nervous system. Meth can induce psychotic symptoms and impairments of cognitive abilities, including executive function (EF). Methods: In this study, we hypothesized the interaction of the neurotoxic effects of Meth on psychotic symptoms and EF performances. The Stroop test evaluated the EF performances, Go/No-Go task, one-back test (OBT), and Wisconsin Card Sorting Test (WCST) in people who use Meth with psychosis (MWP) and without psychosis (MWOP) compared with healthy control participants. Result: The results showed that MWOP and MWP exhibited EF deficits in attention, working memory, and initial conceptualization. Moreover, a deficit in inhibition was observed in MWOP, while poorer processing speed and cognitive flexibility were found in MWP. Conclusion: The correlation between psychotic symptoms and poor EF performances was observed in MWP. These findings underline the interaction of the mechanistic neurotoxic effect of Meth to induce psychological and neurological dysfunctions in people who use Meth.