Answer to Question 1
Several other hypotheses include: reduction of glutamatergic transmission at NMDA receptors, causing an imbalance between glutamatergic and dopaminergic systems in structures of the basal ganglia and the limbic system. On the other hand, treatment with glycine has been shown to significantly improve the negative symptoms of schizophrenic patients under medication with typical antipsychotics.
Answer to Question 2
Generally several days of drug exposure is necessary for the core symptoms of schizophrenia to subside, with the most pronounced effects occurring within the first 6 weeks of exposure and a leveling off at around 12 weeks. Approximately 70 of schizophrenics will show some benefits, but some symptoms may still persist in many of these, and some will exhibit a recurrence of symptoms even with continued use. The most prominent symptoms that are reduced are those categorized as positive symptoms, e.g., hallucinations, delusions, belligerence, disturbed thought processes. Efficacy in reducing negative symptoms is modest at best, and there is little improvement in general cognitive functioning.
The steps of the scientific method, also known as hypothesis testing
Schizophrenia
Dopamine Release Stimulated by Methylphenidate
Positive and Negative Symptoms of Schizophrenia
Relative lifetime risk of schizophrenia
Translation at endoplasmic reticulum–bound ribosomes and the signal hypothesis