For older adults, the damaging effects of aging and stress can impair the ability to learn and sustain memory. Humor, with its associated mirthful laughter, can reduce stress and cortisol, a stress hormone. Chronic release of cortisol can damage hippocampus neurons, leading to impairment of learning and memory.The primary goal of this study was to determine whether watching a humorous video had an effect on short-term memory in an older population.The research team designed a randomized, controlled trial.The study took place at Loma Linda University in Loma Linda, California.The research team recruited 20 normal, healthy, older adults, 11 males and 9 females.The humor group (n = 10, mean = 69.3 ± 3.7 y) self-selected 1 of 2 humorous videos--a Red Skelton comedy or a montage of America's Funniest Home Videos--and watched it for 20 min. A control group (n = 10, mean = 68.7 ± 5.5 y) sat calmly for 20 min and were not allowed to read, sleep, or talk on a cell phone.The Rey Auditory Verbal Learning Test was used to assess short-term memory--learning ability, delayed recall, and visual recognition. Salivary cortisol levels were measured at predetermined times.Learning ability improved by 38.5% and 24.0% in the humor and control groups, respectively (P = .014). Delayed recall improved by 43.6% and 20.3% in the humor and control groups, respectively (P =.029). Within the humor group, delayed recall (43.6%) was significant compared with learning ability (38.5%) (P = .002). At 3 predetermined time points, significant decreases in salivary cortisol were observed in the humor group (P = .047, P = .046, and P = .062, respectively).The study's findings suggest that humor can have clinical benefits and rehabilitative implications and can be implemented in programs that support whole-person wellness for older adults. Learning ability and delayed recall are important to these individuals for a better quality of life--considering mind, body, spirit, social, and economic aspects. Older adults may have age-associated memory deficiencies. However, medical practitioners now can offer positive, enjoyable, and beneficial humor therapies to improve these deficiencies.