Social Buffering During Aversive Conditioning

The purpose of this experiment is to determine the mechanisms through which parental buffering of stress physiology during aversive conditioning diminishes with pubertal development and whether this diminution of effectiveness extends to social buffering by peers (best friends) and/or other unfamiliar social partners (e.g., experimenters).

On visit one, the participant will 1) be seen by a nurse who will complete a pubertal assessment exam, 2) complete questionnaires, including ones on pubertal development, screening for MRI safety, and quality of relations with parents and friends. The participant will also have a chance to experience a simulated MRI in order to determine whether they will be comfortable in an actual MRI.

Within 2 weeks the participant will return to the University where they will undergo the following protocol. Participants will be randomly assigned to one of 4 conditions that differ by who is with them in the scanner room: Primary Parent, Close Friend, Experimenter, No Social Partner. (N=50 per condition, 25 male, 25 female).

Once at the Center for Magnetic Resonance Research, participants and the individual who will be with the participant in the scanning room will undergo an MRI safety screening (the repeat of what was completed over the phone). Girls will be shown to a changing room where the investigators will privately question them about any possibility of pregnancy. All participants will provide a urine sample for oxytocin assessment. Then participants will be shown into the scanning control room and one more safety check will be performed before they enter the scanner room and the scanner. If they are in one of the social buffering conditions, the social buffering partner will also enter the scanning room and will sit to the side of the scanner.

The scanning bed will then be moved into the barrel of the MRI machine. The participant will be wearing head phones to protect his/her hearing and to receive instructions from the control room. The participant will then complete two aversive (fear) conditioning paradigms, none using a social and one using a non-social stimulus. The investigators will use a 3T Siemens Prisma scanner with a standard 32-channel phased array head coil.

Eligibility Criteria:
Inclusion Criteria:

* sufficient vision to complete assent and study procedures
* sufficient hearing to complete assent and study procedures
* sufficient language skills to provide verbal and written assent

Exclusion Criteria:

* Premature birth (less than 37 weeks)
* congenital and/or chromosomal disorders (e.g. cerebral palsy, FAS, mental retardation, Turner Syndrome, Down Syndrome, Fragile X)
* Autism Spectrum Disorders
* history of serious medical illness (e.g., cancer, organ transplant)
* youth taking systemic glucocorticoids
* youth taking beta-adrenergic medications
* diagnoses of psychiatric illness, seizure disorder or other neurological disorders
* contraindications for MRI (implanted medical device; presence of non-removal metal in or on the body, including piercings, orthodontic braces or certain permanent retainers)
* known pregnancy
* tattoos
* history of significant claustrophobia