title: Hydrocortisone impairs hippocampal-dependent trace eyeblink conditioning in post-traumatic stress disorder.
abstract: Trace eyeblink conditioning is a hippocampal-dependent associative learning task that could help evaluate hippocampal function in Post-traumatic stress disorder (PTSD). Since preclinical research has demonstrated that trace eyeblink conditioning can be pharmacologically manipulated by glucocorticoids, this task may shed light on glucocorticoid sensitivity in PTSD. This study assessed baseline and hydrocortisone-mediated changes in trace eyeblink conditioning in patients with PTSD and in healthy controls. A total of 12 patients with PTSD and 12 age- and sex-matched healthy controls participated in a trace eyeblink test 6 h following intravenous administration of 30 mg of hydrocortisone. Spontaneous blink rates were similar between PTSD patients and healthy controls. There was no significant difference in the mean conditioned response between PTSD subjects and healthy controls under placebo conditions. Following hydrocortisone administration, only the PTSD patients demonstrated a significant reduction in conditioned response in contrast to healthy subjects who did not demonstrate any change. Patients with PTSD had increased glucocorticoid sensitivity in the focal brain regions mediating trace eyeblink conditioning.
authors.affiliation: Mood and Anxiety Disorders Program, National Institute of Mental Health, Bethesda, MD 20892-2670, USA. meena.vythi@nih.gov
authors.forename: Meena
authors.initials: M
authors.lastname: Vythilingam
authors.forename: Megan
authors.initials: M
authors.lastname: Lawley
authors.forename: Carlos
authors.initials: C
authors.lastname: Collin
authors.forename: Omer
authors.initials: O
authors.lastname: Bonne
authors.forename: Rajni
authors.initials: R
authors.lastname: Agarwal
authors.forename: Kayleen
authors.initials: K
authors.lastname: Hadd
authors.forename: Dennis S
authors.initials: DS
authors.lastname: Charney
authors.forename: Christian
authors.initials: C
authors.lastname: Grillon
mesh_terms: D000161:Acoustic Stimulation; D000324:Adrenocorticotropic Hormone / Q000097:blood; D000328:Adult; D003215:Conditioning, Eyelid / Q000187:drug effects*; D004576:Electromyography; D005260:Female; D005938:Glucocorticoids / Q000494:pharmacology; D006624:Hippocampus / Q000503:physiopathology*; D006801:Humans; D006854:Hydrocortisone / Q000097:blood / Q000494:pharmacology*; D008297:Male; D010812:Physical Stimulation; D011569:Psychiatric Status Rating Scales; D013313:Stress Disorders, Post-Traumatic / Q000503:physiopathology* / Q000523:psychology*
chemical_list: D005938:Glucocorticoids; D000324:Adrenocorticotropic Hormone; D006854:Hydrocortisone