Characterizing prefrontal cortical activity during inhibition task in methamphetamine‐associated psychosis versus schizophrenia: a multi‐channel near‐infrared spectroscopy study

Abstract

Methamphetamine abuse and dependence, frequently accompanied by schizophrenia-like psychotic symptoms [methamphetamine-associated psychosis (MAP)], is a serious public health problem worldwide. Few studies, however, have characterized brain dysfunction associated with MAP, nor investigated similarities and differences in brain dysfunction between MAP and schizophrenia. We compared prefrontal cortical activity associated with stop-signal inhibitory task in 21 patients with MAP, 14 patients with schizophrenia and 21 age- and gender-matched healthy controls using a 52-channel near-infrared spectroscopy (NIRS) system. Both the MAP and the schizophrenia groups showed significantly reduced activation in the bilateral ventrolateral prefrontal cortex compared with controls; however, only the MAP group showed reduced activation in the frontopolar prefrontal cortex. The MAP group demonstrated significant positive correlations between task performance and hemodynamic responses in the bilateral ventrolateral, polar and left dorsolateral regions of the prefrontal cortex. The MAP and schizophrenia groups demonstrated a significant difference in the relationship of impulsivity to hemodynamic changes in the bilateral premotor cortex. These findings characterize similarities and differences in prefrontal cortical dysfunction between psychosis associated with methamphetamine and schizophrenia. The reduced hemodynamic changes in the bilateral ventrolateral prefrontal cortex suggest a common underlying pathophysiology of MAP and schizophrenia, whereas those in the frontopolar prefrontal cortex point to an impaired state that is either inherent or caused specifically by methamphetamine use.

Methamphetamine‐associated psychosis: Clinical presentation, biological basis, and treatment options

“…Studies have shown that prefrontal cortex (PFC) dysfunction seems to exist for both MAP and schizophrenia, but that distinct differences appear to exist between both groups (Hajebi et al, ; McKetin, Hides, Kavanagh, Saunders, & Dawe, ; Okada et al, ). A recent cross‐sectional study using multichannel near‐infrared spectroscopy demonstrated that MAP and schizophrenia patients both had reduced inhibition control activity in the bilateral ventrolateral PFC, when compared with healthy controls, but that reductions in inhibition control in the frontopolar PFC were only visible in MAP (Okada et al, ). Another study found comparable reductions in PFC activity, between MAP patients and controls, but did not have a schizophrenia comparison group (Yamamuro et al, ).…”

Differential patterns of blood oxygenation in the prefrontal cortex between patients with methamphetamine-induced psychosis and schizophrenia

“…In spite of this, few studies have investigated similarities and differences in brain dysfunction between MAP and schizophrenia. Recently, Okada et al reported that using near-infrared spectroscopy (NIRS), only patients with MAP showed reduced activation in the frontopolar prefrontal cortex during the stop-signal inhibitory task 26 . It has been previously reported that patients with schizophrenia have significant cognitive dysfunctions 27 28 .…”

Psychosis induced by amphetamines

“…A study using inhibition tasks found great similarities in the ventrolateral prefrontal cortex, suggesting similarities in the underlying pathophysiology of psychosis induced by amphetamines and by schizophrenia [22]. However, both this and another study found that, despite great similarities, there are also subtle differences in the prefrontal cortex [23].…”