for healthy control participants: 18-70 years, both sexes, without psychiatric drugs
for patients: from 18- 70 years, both sexes, failed treatment attempts with at least two antidepressants of the appropriate dose and duration.
You may not be if
for patients: treatment with tryptophan, St. John's wort, and/or opioid analgesics in the last month, daily intake of benzodiazepines;
for all participants: presence of psychotic symptoms, alcohol and/or drug addiction, disorder seizures, eating disorder, dementia and other neurodegenerative diseases, epilepsy, intellectual disabilities, severe somatic diseases (including insufficiently controlled arterial hypertension, diabetes and thyroid diseases), active psychotherapeutic treatment (except supportive psychotherapy, which is an integral part of every psychiatric treatment and will be the same in all groups of respondents).
Participants will be excluded if they follow a weight loss diet or take weight loss medication, are pregnant or breastfeeding.
