Final answer:
High levels of the neurotransmitter (Nt) can be associated with psychosis and addiction in Cluster A. In schizophrenia, there is evidence of glutamatergic impairment and decreased NMDAR function, which can lead to excitotoxic effects on the brain. Cannabis use is also linked to increased glutamate levels and earlier onset of psychosis.
Step-by-step explanation:
High levels of Nt, or neurotransmitter, could be associated with psychosis or addiction in Cluster A of psychiatric disorders. In schizophrenia, a Cluster A disorder, there is evidence of glutamatergic impairment and hypofunctional NMDARs. Glutamate overstimulation, especially through non-NMDARs, may lead to an excitotoxic effect on the brain, potentially contributing to the neurodegeneration seen in schizophrenia.
Additionally, research has shown a connection between cannabis use and earlier onset of psychosis. Cannabis can increase glutamate in the brain through various pathways, leading to neurotoxic effects. The involvement of glutamate in the pathogenesis of both schizophrenia and addiction suggests a potential association between high levels of Nt and both psychosis and addiction.