D3211: Healing effect of pet insects on the mental health among the elderly - Teleogryllus emma (Orthoptera: Gryllidae) case

The elderly population is increasing worldwide, with Korea being one of the most rapidly aging societies. There is evidence that animal-assisted therapy has positive effects on mental health, especially in elderly people. The aim of this 8-week randomized, controlled, single-blinded study was to investigate the effect of pet insects on the psychological health of community-dwelling elderly people. Elderly subjects (≥ 65 years old) attending a community center in Daegu, Korea, were enrolled in the study and randomized at a 1: 1 ratio to receive insect therapy and health advice or only health advice. The insect group received 5 crickets in a cage with sufficient fodder and a detailed instruction manual. At baseline and at 8 weeks, all subjects underwent psychometric tests via a direct interview [Geriatric Depression Scale (GDS-15), Mini-Mental State Examination (MMSE), and etc.]. The fMRI (functional magnetic resonance imaging) analysis was used to evaluate the effects of rearing insects on the cognitive function with the Wisconsin Card Sorting Test (WCST). The insect-caring group had significantly lower GDS-15 scores at week 8 (3.20 vs. 4.90, p < 0.01) and a significantly greater change in MMSE scores relative to baseline (1.13 vs. 0.31, p = 0.045). In the fMRI analysis involving the WCST reaction test, increased activation was observed in the right dorsal lateral prefrontal cortex and parietal cortex in insect-rearing group. Caring for insects, which is cost-effective and safe, was associated with a small to medium positive effect on depression and cognitive function in elderly people.