Observational StudyPrefrontal Glutamatergic Modulation by NAC and MBCT for Depression in Youth

Inclusion Criteria:

1. age between 15 years, 0 months to 24 years, 11 months old;
2. presenting with mild depression, defined by meeting DSM-5 criteria for a current major depressive episode, mild severity, or persistent depressive disorder, or other specified depressive disorder (depressive episode with insufficient symptoms to meet criteria for a major depressive episode);
3. medication-naïve or medication free for at least 5 half-lives since the last use of a psychoactive medication, with the exception of stimulants for ADHD;
4. if on ADHD stimulant medication over 2 months prior to screening, willing to maintain stimulant dose constant during the study participation;
5. Tanner stage greater than or equal to III;

Exclusion Criteria:

1. significant suicidal risk, defined by suicidal ideation of type 3, 4 or 5 on the Columbia Suicide Severity Rating Scale (C-SSRS) in the past 3 months, or any lifetime suicidal attempts;
2. current major depressive episode, moderate or severe
3. current or lifetime history of manic or hypomanic episodes, and/or diagnosis of bipolar disorder;
4. current or lifetime history of psychotic disorders, and/or prior diagnosis of schizophrenia spectrum disorders;
5. active or current substance use disorders in the last 3 months, except cannabis or alcohol use disorder, mild;
6. diagnosis of autism spectrum disorder, pervasive developmental disorder, obsessive-compulsive disorder, post-traumatic stress disorders, Tourette's syndrome
7. any contraindication to MRI scanning;
8. pregnancy;
9. history of major neurological disorder (e.g, epilepsy), or head trauma with > 10 minutes loss of consciousness;
10. intellectual disability (IQ less than or equal to 70), as determined by the Weschler Abbreviated Scale of Intelligence (WASI);
11. previous participation in any mindfulness-based treatment;
12. initiating psychotherapy within 2 months prior to screening, or planning to initiate psychotherapy during study participation; if on therapy, frequency and type should remain stable for 2 months prior to enrollment and during study participation;
13. no current diagnosis of asthma
14. history of allergic reaction to N-acetylcysteine