Two

The first source that I found relating to this idea was called Pet Therapy & Institutionalized Elderly. In this article a study was conducted with 144 cognitively unimpaired elderly individuals who happened to live in nursing homes. The subjects were split into 3 groups: 1 that was to receive a plant, 1 group that got a canary and the last group that was given nothing. Initially all the participants completed a series of tests looking into their mental state, gauging their perception of their quality of life, and self evaluating their psychopathological symptoms. After the participants spent 3 months living with their new plants, pets, or nothing, they were readministered the same series of tests. The results showed that while caring for a plant impacted the elderly to some degree, it was those participants who received a canary who benefited the most. They had decreased depression symptoms and an increased perception of their current quality of life as well as an overall improved psychological well being.