The goal of our research is to check the levels of D-Serine, Glycine, and other Glutamatergic amino acids, in patients with First Psychotic Episode (FPE). These patients are in the early stage of the disease, treated with neuroleptics for short periods of time, and are usually hospitalized for the first time. The hypothesis of the research is that we will find low levels of Glycine and D-Serine in these patients. Following an Anti-psychotic treatment we will expect these levels to return to the norm, and that this correction will be accompanied by a reduction of positive and negative symptoms.