Physiological responses by college students to a dog and a cat: Implications for pet therapy

Companion animals are an important part of our social world. We often talk to them as if they were humans and some even refer to pets as their children. They are a source of comfort, love, and their time with us is often followed by grieving when they die. The therapeutic benefits of owning a pet have been suggested by a number of studies. Cardiovascular health benefits have been found to be related to dog ownership, both in terms of length of survival (Friedmann, Katcher, Lynch, & Thomas, 1980; Friedmann & Thomas, 1995) and in general cardiovascular health (Friedmann, Thomas, Stein, & Kleiger, 2003; Serpell, 1991). An aspect of pet therapy that has not been fully explored is possible differences between species in their physiological effects on participants. Allen, Blascovitch, and Mendes (2002) found no significant differences in blood pressure and pulse rate between dog owners and cat owners. After combining dog and cat data, it was found that pet owners, as compared to non pet owners, had significantly lower resting pulse rates, lower systolic and diastolic blood pressure, and exhibited significantly lower reactivity on all three measures following a stressful arithmetic task. As noted by Friedmann, Thomas, and Eddy (2000), most of the studies on short term physiological responses to an animal have used dogs, mostly because of convenience and popularity as pets. Serpell (1991) found that cat owners showed a significant short term reduction in minor health problems but not after six months. Dog owners showed a dramatic increase in the frequency and duration of walking, but cat owners showed no significant changes over a ten month period. Friedmann and Thomas (1995) found that both dog ownership and social support were positively related to one-year survival status after an acute myocardial infarction, but that cat ownership was negatively associated with one-year survival status. In addition to long term effects of pet ownership research has also focused on the effects of a relatively brief exposure to either a familiar or unfamiliar animal. The physiological effects of a brief exposure to a dog have varied according to experimental procedures, the age of participants, the types of independent variables employed, and whether a familiar or unfamiliar animal was used. Allen, Blascovich, Tomaka, and Kelsey (1991) found that participants in the presence of their own dog and the experimenter showed less physiological reactivity following a stressful arithmetic task in comparison with any other condition. Friedmann, Katcher, Thomas, Lynch, and Messent (1983), using an unfamiliar dog with 9-16 year-old children, found a reduction in blood pressure associated with a dog's presence, although results varied when the dog was introduced in the first half as opposed to the second half of the test condition. Wilson (1987), in a study of college students, assessed the effects of reading aloud, reading quietly, and petting a friendly but unfamiliar dog on measures of six dependent variables: systolic blood pressure, diastolic blood pressure, pulse rate, mean arterial pressure, Spielberger's Anxiety Questionnaire, and the Pet Attitude Inventory. Results showed that reading aloud consistently resulted in the highest increases in blood pressure while reading quietly was consistently associated with the lowest levels of blood pressure. It was concluded that interacting with the dog was more stressful than reading quietly but less stressful than reading aloud. Several studies assessed blood pressure and pulse rate changes during a condition in which participants physically interacted with a dog. Friedmann, Katcher, Meislich, and Goodman (1979) found that both systolic and diastolic blood pressure was significantly higher during a petting condition than a resting condition. However, both systolic and diastolic blood pressure were significantly higher during a reading condition than during the petting condition. …