Examination of Glutamate and mGluR5 in Psychiatric Disorders

Inclusion Criteria: General inclusion criteria: * Subjects will be between the ages of 18-70 years old * English speaking * No other DSM-5 diagnosis present, besides required as below Inclusion criteria for acute depressed subjects: * Clinical diagnosis of a current depressive episode * Medication-free for at least 2 weeks or medicated with a permissible medication Inclusion criteria for PTSD subjects: * Clinical diagnosis of current PTSD as per DSM-5 * Medication free for at least 2 weeks or medicated with a permissible medication Inclusion criteria for healthy controls: * No current, or history of, any DSM-5 diagnosis Exclusion Criteria: * Have a current or past significant medical, neurological or metabolic disorder or head injury that lead to significant long term decline in cognitive abilities as seen by decline in grades or work performance * Have significant medical illness such that would contraindicate study participation based on above criteria and PI/MD history review * Have active, significant suicidal ideation * Have implanted metallic devices or any MR contraindications * Are women who are pregnant or breastfeeding * Met DSM-5 criteria for mild substance use disorder (except nicotine and marijuana) within the past 6 months or met DSM-5 criteria for moderate to severe substance use disorder (except nicotine and marijuana) within the past year * Have history of prior radiation exposure for research purposes within the past year such that participation in…