The Effects of Propranolol, Hydrocortisone, and Morphine on Military-Relevant Performance Outcomes

Inclusion Criteria: * Male and non-pregnant, non-lactating females 18 to 40 (inclusive) years of age. * Females of child-bearing potential must be on some form of birth control, if sexually active (e.g., oral contraceptive, condom, intrauterine device, etc.) * Score of 80% or greater on a "Volunteer Comprehension Assessment" test. * Score equal to or greater than 54 on the Fear of Spiders Questionnaire. * Body weight between 91 and 250 pounds (inclusive). * Live close enough to be able to commute to Walter Reed Army Institute of Research during the study participation. Exclusion Criteria: * Contraindications due to study medications, including a history of allergic/hypersensitivity reactions to a beta blocker, an opiate agonist or a steroid, or a history of other adverse reactions to these classes of drugs (such as an episode of steroid psychosis). * A history of allergic reactions to a spider bite. * A history of abuse or addiction to illicit drugs (including marijuana) or prescribed medication (e.g., opioid) (diagnosed or suspected based on the medical history). * Use a nicotine product (e.g., cigarette, cigar, vape) more than 3 days per week. * Self-reported caffeine use in excess of 600 mg (e.g., approximately 10 caffeinated sodas or approximately 29 ounces of brewed coffee) per day on average or not being able to go without caffeine during the In-Lab visits. * History of neurologic disorder (to include but not limited to epilepsy, hydrocephalus, MS). An infrequent or …