This study comprises two experiments in which the stress response is pharmacologically modeled. Participants in the study will have two study visits. During Visit 1, participants will undergo a psychiatric assessment, complete neuropsychological tasks, and have their IQ measured. During Visit 2, participants will be given hydrocortisone and/or yohimbine. Blood will be collected before and during this. Participants will then perform two experiments. In one experiment, participants will hear a story with emotional and non-emotional segments; in a second experiment, participants will view both emotional and non-emotional stimuli.