Cognition and Related Neural Findings on Methamphetamine Use Disorder: Insights and Treatment Implications From Schizophrenia Research

Abstract

Despite the prevalence of methamphetamine (meth) use disorder, research on meth is disproportionately scarce compared to research on other illicit drugs. Existing evidence highlights cognitive deficits as an impediment against daily function and treatment of chronic meth use. Similar deficits are also observed in schizophrenia, and this review therefore draws on schizophrenia research by examining similarities and differences between the two disorders on cognition and related neural findings. While meth use disorder and schizophrenia are two distinct disorders, they are highly co-morbid and share impairments in similar cognitive domains and altered brain structure/function. This narrative review specifically identifies overlapping features such as deficits in learning and memory, social cognition, working memory and inhibitory/impulse control. We report that while working memory deficits are a core feature of schizophrenia, such deficits are inconsistently observed following chronic meth use. Similar structural and functional abnormalities are also observed in cortical and limbic regions between the two disorders, except for cingulate activity where differences are observed. There is growing evidence that targeting cognitive symptoms may improve functional outcome in schizophrenia, with evidence of normalized abnormal brain activity in regions associated with cognition. Considering the overlap between meth use disorder and schizophrenia, targeting cognitive symptoms in people with meth use disorder may also improve treatment outcome and daily function.

Sex differences in the neurochemistry of frontal cortex: Impact of early life stress

“…The frontal cortex is well‐known for its role in synthesizing a range of information, to ultimately result in cognitive, affective, and motor control important for executive function (Ebbesen et al., 2018; Evans & Hampson, 2015; Floresco, 2013; Miller, 2000; Putt et al., 2019). Dysfunction in this region is associated with various psychiatric disorders (Casey & Jones, 2010; Gold et al., 2020; Guerin et al., 2019; Kim & Ganella, 2015; Lewis & Gonzalez‐Burgos, 2000; Paus & Giedd, 2008; Remijnse et al., 2009). There is evidence of sexual dimorphism in the frontal cortex in humans and in rodents (Gennatas et al., 2017; Lenroot & Giedd, 2010; Velasco et al., 2019), which may explain at least in part the sex‐dependent prevalence of different psychiatric conditions (Auerbach et al., 2018; Coffino et al., 2019; Mohebbi et al., 2019; Zagni et al., 2016).…”

“…The frontal cortex matures slower than other brain regions in humans and rodents (Case y & Jones, 2010; Drzewiecki et al., 2020; Ganella, et al., 2018; Paus & Giedd, 2008; Shaw et al., 2008; Steinberg, 2008; Zbukvic & Kim, 2018), and it is particularly susceptible to experience‐dependent changes, again in humans and in rodents (Charlton et al., 2019; Eiland & Romeo, 2013; Gee et al., 2013; Guerin et al., 2019; Shaw et al., 2019). Indeed, many mental disorders have been linked to frontal cortex dysfunction following stress early in life (Casey & Jones, 2010; Gee et al., 2018; Paus & Giedd, 2008; Shaw et al., 2019).…”

Verbal learning impairment in adolescents with methamphetamine use disorder: a cross-sectional study

“…Third, we did not record the time of abstinence since last MA use. Since, it might be possible that cognitive effects recuperate after MA abstinence (see [22,51]), future longitudinal studies need to control for this variable.…”

Psychostimulant use disorder emphasizing methamphetamine and the opioid -dopamine connection: Digging out of a hypodopaminergic ditch

“…Schizophrenia is associated with pronounced thought disorder and cognitive deficits mediated by the parietal cortex, such as difficulties with selective visual attention, while visual and tactile hallucinations appear to be more prevalent in acute methamphetamine-induced psychosis. Notably, the clinical significance based on this differential in symptoms provides a basis to distinguish between acute methamphetamine psychosis that represents a psychotic disorder distinct from schizophrenia [57].…”