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Physiological Responses by College Students to a Dog and a Cat: Implications for Pet Therapy


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The effects of physical contact with a dog and a cat on blood pressure and pulse among male and female college students were examined. The final sample consisted of 62 participants (28 males and 34 females). It was tentatively hypothesized that participants would show a reduction in blood pressure while handling both a dog and a cat. It was also speculated that male and female participants would react differently to a dog versus a cat. There were no significant blood pressure or pulse differences in response to a dog vs. a cat, nor were there significant gender differences although females generally had a lower blood pressure than males. There were no significant changes in blood pressure or pulse while participants held an animal, but a significant decrease in diastolic pressure occurred immediately following holding an animal. Results partially support previous findings of a reduction in blood pressure associated with animal contacts. Implications for pet therapy were discussed.
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Author info: Correspondence should be sent to: Dr. John Somerville, Dept. of
Psychology, University of Northern Iowa, Cedar Falls, IA 50614.
North American Journal of Psychology, 2008, Vol. 10, No. 3, 519-528.
Physiological Responses by College Students to a
Dog and a Cat:
Implications for Pet Therapy
John W. Somervill, Yana A. Kruglikova, Renee L.
Robertson, Leta M. Hanson, Otto H. MacLin
University of Northern Iowa
The effects of physical contact with a dog and a cat on blood pressure
and pulse among male and female college students were examined. The
final sample consisted of 62 participants (28 males and 34 females). It
was tentatively hypothesized that participants would show a reduction in
blood pressure while handling both a dog and a cat. It was also
speculated that male and female participants would react differently to a
dog versus a cat. There were no significant blood pressure or pulse
differences in response to a dog vs. a cat, nor were there significant
gender differences although females generally had a lower blood pressure
than males. There were no significant changes in blood pressure or pulse
while participants held an animal, but a significant decrease in diastolic
pressure occurred immediately following holding an animal. Results
partially support previous findings of a reduction in blood pressure
associated with animal contacts. Implications for pet therapy were
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. Baun, Bergstrom, Langston,
Somerville, Kruglikova, Robertson, Hanson, & MacLin PETS
and Thomas (1984) found that the blood pressure and pulse rate of
participants increased significantly at the beginning of the petting
session, presumably because of the initial excitement associated with
their dogs entering the room. The major finding was that the greatest
decrease in blood pressure was among participants who petted their own
dog as opposed to an unfamiliar dog. Vormbrock and Grossberg (1988)
found that petting a dog without verbalization and a rest condition
produced the lowest blood pressure as compared to the four other
conditions studied.
Minimal research has been done to assess gender differences in
response to animals. Allen et al. (2002) noted that no consistent gender
differences have been reported.
In summary, with some exceptions, a reduction in blood pressure has
been reported in most studies following limited contact with a dog. The
goals of the present study were: (a) to assess the effects of limited
exposure to an unfamiliar dog versus an unfamiliar cat on blood pressure
and pulse rate on male and female college students, and (b) to increase
physical interaction with the animals by having participants hold each
animal in their lap for a five minute period. It is tentatively hypothesized
that participants will show a reduction in blood pressure while handling
both a dog and a cat.
As noted previously, previous research has failed to support a
significant difference in physiological reactions to a dog and cat.
However, it was speculated that there may be gender differences in
reactions to different species.
The study consisted of two phases. The first consisted of a brief
survey administered in a mass testing situation along with other short
surveys involving unrelated studies. The second phase consisted of the
primary experimental study involving physiological reactions to dogs and
In phase 1, participants in the mass screening were 178 students (86
males and 92 females) from introductory psychology classes who elected
to participate in order to fulfill a research requirement or an acceptable
Informed consents were obtained and each participant was asked to
respond to a one page questionnaire entitled Cat and Dog Preference
Survey consisting of demographic information, including gender, age,
marital status, and ethnic origin. Participants were asked to check one of
three options: (a) I like dogs, (b) I do not like dogs, and (c) I neither like
nor dislike dogs. The same three options were also requested for cats.
Participants were also asked to check “Yes” or “No” if they had a dog or
a cat currently living with them or their parents.
Participants were excluded from further participation if they had dog
or cat allergies, strong fears of dogs or cats, or problems with
hypertension. Of the 178 participants in phase 1, four reported being
allergic to dogs and cats, ten reported being allergic to cats, and two
reported being allergic to dogs. Two persons indicated a strong fear of
cats, and five persons indicated a strong fear of dogs. Two persons
reported problems with high blood pressure.
Only students who participated in the mass screening were eligible
for phase 2. A total of 62 participants, 28 males and 34 females, signed
up for and completed phase 2. The age range for males was 18 to 29
(mean= 20.04 yrs.), and for females was 18 to 24 (mean= 19.21 yrs.).
Median age for both males and females was 19. Of the 28 males, 22 were
Caucasian, four were African American, and one was Hispanic. Of the 34
females, 32 were Caucasian, one was African American, and one was
other (unspecified).
An informed consent for phase 2 was obtained from each participant.
One of three undergraduate female research assistants took all blood
pressure and pulse rate readings. The blood pressure monitor was
demonstrated to each participant in advance. All blood pressure readings
were taken with an automatic digital blood pressure monitor (Health-O-
Meter Model 7631).
During the experiment, a total of ten blood pressure and pulse
readings were taken, one at the beginning and one at the end of nine 5-
minute intervals. During the third and seventh 5-minute interval, each
participant held either a dog or cat in their laps for the full 5 minute
period. The order of presentation of a dog or cat was alternated.
Measurements taken before and after the first, fifth, and ninth 5-minute
interval served as baselines during which no animal was present.
Between readings, casual conversation was encouraged. A second person
was always in the room to ensure that the animal remained in the
participant’s lap during the third and seventh 5 minute time period..
The dog used for all participants was a 14 pound blond Shi-Tzu. Two
cats were used, both were obtained from the local humane shelter. All
animals were selected because of their gentleness, friendliness towards
people, and non-aggressive behaviors. All animals were examined for
parasites or fleas and had received all necessary shots.
There were five phases in this experiment: (a) an initial baseline with
no animal, (b) the first presentation of a dog or a cat, (c) a second
baseline with no animal, (d) the second presentation of a dog or a cat, and
(e) a third baseline with no animal. Two measures, blood pressure and
pulse, were taken for each phase, one at the beginning of the 5 minute
Somerville, Kruglikova, Robertson, Hanson, & MacLin PETS
period, and one at the end. A 5-minute interval separated each of these
ten measures.
The first procedural question was whether or not the two measures
taken within each of the three baseline phases, during which no animal
was present, significantly differed. No significant difference between the
first and second measure for each of the three baselines was obtained.
Therefore, the two measurements for each baseline were averaged.
Two different cats were used during the experiment. Further analysis
with t tests indicated that there were minimal differences between the
first and second cat. Therefore, in subsequent analyses, data for the two
cats were combined.
The first question was whether blood pressure and pulse would
significantly differ in reactions to a dog or cat. A related question was if
there was a sequence effect depending on whether the dog was presented
first or the cat was presented first. To answer both of these questions, a
series of independent t tests were conducted to determine if there was a
significant difference between systolic blood pressure, diastolic blood
pressure and pulse rate during the following time periods: (a) holding a
cat, (b) the baseline subsequent to holding a cat, (c) holding a dog, and
(d) the baseline subsequent to holding a dog. Results of t tests comparing
the sequence of holding a cat first vs. holding a dog second were non
significant for systolic pressure, t(1,61) = .78, n.s., diastolic pressure,
t(1,61) = -1.05, n.s., or pulse, t(1,61) = .71, n.s. Likewise, comparisons
involving the sequence of holding a dog first vs. holding a cat second
were non significant for systolic pressure, t(1,61) = 1.45, n.s., diastolic
pressure, t(1,61) = .70, n.s.,or pulse, t(1,61) = .750, n.s. Consequently,
the order of presentation was ignored in subsequent analyses and the data
for dogs and cats were combined. No support was obtained for the
hypothesis that holding a dog would result in lower blood pressure or
lower pulse rate than holding a cat. Failure to find significant differences
in response to a dog or cat is consistent with results obtained by Allen et
al. (2002).
Another procedural issue was to determine whether there were significant
differences between the three baseline periods for systolic blood
pressure, diastolic blood pressure and pulse. Paired sample t tests
revealed significant difference between the first and third baseline for
both systolic blood pressure, t (1, 61) = 3.591, p < .001, and diastolic
blood pressure, t (1, 61) =2.096, p < .005; and the second and third
baseline for both systolic blood pressure, t (1, 61) = 2.944, p < .005, and
diastolic blood pressure, t (1, 61) = 2.008, p < .049. A significant
difference was also obtained for pulse rate between the first and second
baseline, t (1, 61) = 2.295, p < .025, and the first and third baseline, t (1,
61) = 2.82, p < .006. These differences largely reflect a gradual reduction
in both blood pressure and pulse rate over the course of the experimental
session. Figure 1 presents the means for systolic pressure, diastolic
pressure, and pulse for each of the five phases: 1) baseline, 2) holding
animal, 3) baseline, 4) holding animal, and 5) baseline.
Physiological Measures
T1 T2 T3 T4 T5
Measurement Intervals
M e a n M ea su re m en t
FIGURE 1 Means for Systolic Pressure, Diastolic Pressure, and Pulse for
Five Phases: 1) Baseline, 2) Holding Animal, 3) Baseline, 4) Holding
Animal, and 5) Baseline.
The primary hypothesis was that physical contact with an animal will
lead to a decrease in blood pressure and pulse rate. Recall that the data
for dogs and cats were combined. The time periods during which an
animal was held in the participant’s lap were compared with the time
periods during which no animal was present. A separate one way analysis
of variance was performed for all five time periods for systolic blood
pressure, diastolic blood pressure and pulse rate. The F value for systolic
blood pressure was not significant, F (4,240) = .671, p < .613, and the F
value for pulse rate was not significant, F (4,240) = 2.373, p <. 053. The
only significant finding was that diastolic blood pressure was lower for
the baselines immediately following the animal present conditions than
during the actual animal conditions, F (4,240) = 4.28, p <. 002. Multiple t
Somerville, Kruglikova, Robertson, Hanson, & MacLin PETS
tests yielded significant differences between diastolic blood pressure
during first and third baselines, t (1,61)= 2.72, p < .008; the first animal
condition and the second baseline, t (1,61)= 2.97, p < .004; the first
animal condition and the third baseline, t (1,61)= 3.303, p < .002; and the
second animal condition and the third baseline, t (1,61)= 2.293, p < .025.
As indicated in Figure 1, every time the baseline followed a session with
an animal, there was a small but significant decrease in diastolic blood
pressure. In summary, very limited support was provided for the
hypothesis that physical contact with an animal would lead to a decrease
in blood pressure. The decrease was only for diastolic pressure and only
occurred during the baseline periods after holding an animal.
There were three other variables of interest: (1) whether the
participant liked or disliked dogs or cats, (2) ownership of a dog or cat,
and (3) gender of the participants. Data on dog and cat preferences and
dog and cat ownership were obtained from all but one of the 62
Of the 61 participants, 53 (85%) reported that they liked dogs, only 2
(3.2%) reported that they disliked dogs, and 6 (9.7%) reported that they
neither liked nor disliked dogs. Cats were not as popular; 40 (64.5%)
reported that they liked cats, 7 (11.3%) disliked cats, and 14 (22.6%)
neither liked nor disliked cats.
There were four categories of dog and cat ownership: a) owned only a
dog, b) owned only a cat, c) owned both a dog and a cat, and d) owned
neither a dog nor a cat. Ownership was defined as either owning an
animal at their current address while in school or owning one at their
home address. Of 61 participants, 19 (30.6%) reported that they owned
only dogs, 11 (17.7%) owned only cats, 16 (25.8%) owned both dogs and
cats, and 16 (25.8%) did not own either a dog or a cat.
No significant test differences were obtained for the four ownership
conditions between any of the five measurement periods for systolic
blood pressure, diastolic blood pressure, or pulse rate.
When the combined data for all five time periods for males and
females were compared, males had slightly higher systolic blood
pressure, F (1, 60) =4.494, p < .038, but this was not significant given the
large number of t tests conducted. There was not a significantly higher
diastolic pressure, F (1, 60) = 3.316, p < .074. Females had significantly
higher pulse rate, F (1, 60) = 7.748, p < .007.
There were no significant differences between males and females
during the time period while an animal was held on their lap for either
systolic blood pressure, F(1,60)= .226, p < .636, or diastolic blood
pressure, F(1,60)= 1.491, p < .227. However, females had a significantly
higher pulse rate, F (1, 60) = 6.289, p < .015.
During the time period immediately following holding an animal,
females also showed significantly lower systolic blood pressure, F (1, 60)
= 23.64, p < .001, but not diastolic blood pressure, F (1, 60) = 4.52, p <
.038, given the large number of t tests made. During the same time
period, females also had a significantly higher pulse rate, F (1, 60) =
6.911, p < .011. In summary, there were no gender differences in
physiological responses while participants held an animal, but females
did show a decrease in systolic blood pressure and a higher pulse rate
during the time period after holding the animal.
No support was found for the possibility that physiological responses
to a dog would differ significantly from physiological responses to a cat.
In the present study, there were no significant differences in systolic
blood pressure, diastolic blood pressure or pulse between holding a cat
for 5 minutes and holding a dog for 5 minutes, nor were there any
significant differences in response to holding a dog or cat by male and
female participants. In regard to physiological consequences, therefore,
it does not appear to matter if a person is holding a cat or a dog. Since
many pet therapy situations involve a similar type of limited exposure,
the present study suggests that comparable results may be expected for
both dogs and cats.
The major hypothesis that physical contact with an animal would lead
to a decrease in blood pressure and pulse was only partially supported.
No significant changes occurred while an animal was being held on
participants’ laps. However, during time periods immediately after an
animal was removed, a small but significant decrease in systolic blood
pressure occurred. It is possible that potential autonomic effects of
holding an animal may be delayed until a brief period after the animal
has been removed. In general, these results lend only minor support to
the findings by others that contact with a dog or cat lowers blood
pressure. However, in the present study, the fact that there was also a
gradual reduction in blood pressure over time considerably weakens
conclusions about effects attributable to handling a dog or cat.
In designing the study it was considered possible that liking or
disliking an animal might influence autonomic responses. Therefore,
each participant was asked in advance of the study whether they liked,
disliked, or neither liked nor disliked a cat or a dog. Results, however,
indicated that few persons expressed a dislike for either cats or dogs.
More people reported liking dogs than reported liking cats, a finding
consistent with stereotypes about the friendliness of dogs and the
aloofness of cats.
Previous research has suggested that persons may have different
autonomic responses to their own companion animal than to an
unfamiliar animal. One also might expect that ownership of a dog or cat
Somerville, Kruglikova, Robertson, Hanson, & MacLin PETS
might influence responses to an unfamiliar dog or cat. However, there
were no significant differences in autonomic responses to an unfamiliar
dog or cat between dog owners, cat owners, owners of both cats and
dogs, and participants who owned neither a cat nor a dog. It is tempting
to speculate that in a pet therapy situation, possible therapeutic effects
may be independent of previous pet ownership.
In the present study, few significant gender differences were
obtained. Females showed a higher increase in pulse rate than males
when holding an animal. In general, females showed significantly lower
systolic blood pressure than males, but had a significantly higher pulse
rate. This difference, however, was unrelated to the presence or absence
of an animal.
In summary, the present study suggests that in the typical pet therapy
paradigm one would not expect different physiological effects from the
use of a dog or a cat, and relatively minimal changes in blood pressure or
pulse rate while the person is interacting with an animal.
The difference between long term ownership of a companion animal
versus short term exposure to an animal might be compared to the
difference between raising your own child versus a short term visit by
someone else’s child. Pet ownership, like raising a child, involves care
taking and an emotional attachment that you have developed over months
and years. While you may enjoy petting someone else’s dog or cat, the
interaction is not likely to be the same as the interaction with your own
companion animal. Thus, it is not surprising that the positive, long term
cardiovascular benefits associated with pet ownership affect survival and
general cardiovascular health, but brief exposure to an animal may have
minimal or no long term health benefits. However, even if there are only
minor physiological changes, numerous anecdotal reports suggest that
patients in a variety of settings enjoy interacting with companion
animals. The benefits of pet therapy may be primarily related to these
pleasurable experiences.
An obvious limitation to the present study is that findings with
college students may not be generalized to other age groups or non-
college settings selected for pet therapy such as nursing homes, hospitals,
and prisons.
Allen, K. M., Blascovich, J., & Mendes, W. B. (2002). Cardiovascular reactivity
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... Included studies were conducted in eight countries: the USA (28 studies) (Wilson, 1987;Folse et al., 1994;Somervill et al., 2008;Adamle et al., 2009;Gee et al., 2014;Polheber and Matchock, 2014;Stewart et al., 2014;Crossman et al., 2015;Crump and Derting, 2015;Gee et al., 2015;Barker et al., 2016Barker et al., , 2017Shearer et al., 2016;McDonald et al., 2017;Trammell, 2017;Delgado et al., 2018;Hall, 2018;Jarolmen and Patel, 2018;Pendry et al., 2018Pendry et al., , 2019aPendry et al., ,b, 2020Foreman et al., 2019;Pendry and Vandagriff, 2019;Trammell, 2019;Chakales et al., 2020;Haefelin et al., 2020;Robino et al., 2021); Canada (nine studies) (Dell et al., 2015;Binfet and Passmore, 2016;Binfet, 2017;Fiocco and Hunse, 2017;Binfet et al., 2018;Ward-Griffin et al., 2018;Silas et al., 2019;Griscti and Camilleri, 2020); the UK (four studies) (Grajfoner et al., 2017;Charles and Wolkowitz, 2019;Wood et al., 2018;Thelwell, 2019); Germany (two studies) (Buttelmann and Rompke, 2014;Lass-Hennemann et al., 2014); Spain (one study) (Pena Gil et al., 2019); Austria (one study) (Gebhart et al., 2020); the Czech Animal-assisted interventions in universities • Levels of sNGF were undetectable for most students and therefore not subjected to analysis. ...
... In terms of the animals involved in the intervention, 39 studies included dogs, ranging from 1 to 40 dogs. Other studies included a combination of dogs, a rabbit and a bird (Robino et al., 2021); one dog and two cats (Somervill et al., 2008); 10 dogs and 12 cats (Pendry et al., 2019b); 16 dogs and 14 cats (Pendry and Vandagriff, 2019); 9 dogs and 12 cats (Pendry et al., 2018); horses (number not specified) (Charles and Wolkowitz, 2019); a dog, fish and plant (Buttelmann and Rompke, 2014); and a therapy dog and an animatronic dog (Haefelin et al., 2020). A large majority of studies may include dogs due to the level of training that is guaranteed for therapy dogs. ...
... Among the 47 studies, 25 retained all participants from pre-test to post-test [includes 13 RCTs (Wilson, 1987;Polheber and Matchock, 2014;Crossman et al., 2015;Crump and Derting, 2015;Binfet and Passmore, 2016;Binfet, 2017;Fiocco and Hunse, 2017;Grajfoner et al., 2017;Jarolmen and Patel, 2018;Pendry et al., 2019b;Pendry and Vandagriff, 2019;Trammell, 2019;Griscti and Camilleri, 2020), 7 quantitative non-randomized (Somervill et al., 2008;Gee et al., 2015;Muckle and Lasikiewicz, 2017;Binfet et al., 2018;Pena Gil et al., 2019;Thelwell, 2019;Machova et al., 2020), 4 quantitative description studies (Gee et al., 2014, Delgado et al., 2018Silas et al., 2019;Chakales et al., 2020) and 1 mixed methods study ]. Attrition rates among RCTs ranged from 2% (McDonald et al., 2017) to 29% (Hall, 2018), 11% (Robino et al., 2021) to 14% (Wood et al., 2018) for quantitative non-randomized, 9% (Stewart et al., 2014) among quantitative description and 78% among a mixed methods study, which included a 3-month follow-up (Dell et al., 2015). ...
With levels of stress and anxiety rising among the university community, universities worldwide are implementing animal-assisted interventions (AAIs) on campus. However, to date, little is known about how to implement these initiatives. Questions also remain as to the impact of evaluated AAIs on health and wellbeing. Therefore, this study sought to review the implementation and effectiveness of previous AAIs in university settings. Electronic databases ProQuest Central, Gale and 16 databases within EBSCOHost were searched with key words, such as AAI, and university or college students for relevant articles. Inclusion criteria included primary research studies that measured a health, wellbeing or behavioural outcome. A total of 47 articles met inclusion criteria, including 24 RCTs. There was limited reporting on the implementation of AAIs in the higher education setting. A total of 11 different mental health and behavioural outcomes have been summarized, with stress, anxiety and mood providing favourable results. An AAI on campus may provide a form of stress and anxiety relief for the university community. Other mental health and behavioural outcomes require further research to determine their effectiveness. These findings highlight that an AAI on campus could potentially provide a form of stress and anxiety relief, and could be a strategy for addressing rising levels of psychological stress and mental health issues among university students and staff in Australia and internationally.
... Haggerty and Mueller (2017) reported 86% of programs in higher education featured dogs only, 5% feature cats and dogs, and 10% incorporate dogs and cats with other species. In a recent review (Cooke et al., 2022) authors noted that of 83% of studies included dogs exclusively, 8.5% of studies included dogs and cats Pendry et al., 2018;Pendry & Vandagriff, 2019;Somervill et al., 2008), while some studies combined dogs with other species (Buttelmann & Rompke, 2014;Charles & Wolkowitz, 2019;Robino et al., 2021). Suggested reasons for the overrepresentation of dogs include that they can be expected to have completed a considerable amount of screening and training (Cooke et al., 2022), which may enhance participant safety and wellbeing. ...
... Furthermore, cat ownership has been shown to decrease depression (Turner & Rieger, 2001) and improve empathy and anxiety in children with autism (Carlisle et al., 2021). In addition, when cats have been incorporated into AAIs along with dogs, researchers found significant positive effects on emotion, cortisol and alpha-amylase levels (Pendry et al., 2018;Vandagriff et al., 2021), and reduced blood pressure after physical contact with a cat equal to those observed with a dog (Somervill et al., 2008). Furthermore, the potential of cat-featured AAIs may be enhanced by teaching participants 'cat-appropriate' human behaviour, which has been shown to improve affiliative behavior of cats towards humans (Haywood et al., 2021). ...
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As most university-based animal-assisted interventions (AAIs) feature interactions with dogs, little is known about the feasibility of providing opportunities to interact with cats. Few studies have examined employee or student interest in interacting with on-campus cats, and virtually nothing is known about the role of participants’ characteristics and perceptions in shaping their interest. Using a cross-sectional survey, the current study assessed participants’ responsiveness toward an on-campus cat visitation program in a sample of higher-education staff and students (n = 1,438). Using hierarchical regression analyses, responsiveness was modeled on participants’ demographic characteristics (i.e., employee or student, gender, age), the personality trait of emotionality, perceived stress, prior animal experiences (i.e., cat/dog ownership, cat allergy and phobia, responsiveness toward on-campus dogs), and perceived risks of on-campus cats. Regression analyses indicated that emotionality (β = 0.15, p < 0.001), being female (β = 0.06, p < 0.05), being open to a dog visitation program (β = 0.50, p < 0.001), and being a cat owner (β = 0.13, p < 0.001), were positively associated with responsiveness toward a cat visitation program, whereas having a cat phobia (β = −0.22, p < 0.001), cat allergy (β = −0.13, p < 0.001), being a dog owner (β = −0.08, p < 0.001), and perceiving interactions with cats as risky (β = −0.14, p < 0.001) were negatively associated. Interestingly, although we hypothesized positive associations between perceived stress and responsiveness, these associations were not significant (β = −0.03, p = 0.305), nor did we observe significant differences by student or employee status (β = 0.02, p = 0.610). These findings are the first to elucidate the role of staff and students’ features in shaping responsiveness toward on-campus cats in higher education, which may inform the design and implementation of on-campus visitation programs.
... Animals have also been shown to have noticeable effects on measurable physiological correlates of stress. Recent research conducted by Somerville et al. [48] examined the effects of physical contact with a dog and a cat on blood pressure and pulse among 62 university students (28 males and 34 females). The participants who held a dog or cat experienced an immediate decrease in diastolic blood pressure. ...
... However, this reduction in blood pressure did not occur during the contact with an animal and instead only occurred after the contact had taken place. There were no significant gender differences found, however females did have lower blood pressure than males [48]. Interacting with a dog has also been shown to decrease cortisol levels, and therefore indicate a reduction in stress levels in university students, who themselves did not own a pet. ...
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Abstract: University students have been found to have higher rates of psychological distress than that of the general population, which reportedly rises significantly upon starting university and does not return to pre-university levels throughout their time in university. It is therefore highly important to find ways to improve student health and well-being. One way that may help is by interacting with animals. Therefore, the purpose of this study was to determine whether interacting with a dog would have a positive effect on university students' mood and anxiety. This study assigned 82 university students to either the experimental condition (dog interaction, n = 41) or to the control condition (dog video, n = 41). The students completed the Positive and Negative Affect Schedule-Expanded Form (PANAS-X), State-Trait Anxiety Inventory (STAI) and the Pet Attitude Scale before their assigned conditions, to evaluate their mood and anxiety levels and attitudes to animals. The participants again completed the STAI and PANAS-X Form after their condition, to assess for possible changes in anxiety and mood. The findings of the study indicated that all participants, regardless of condition, experienced a reduction in their anxiety and an improvement in their mood across time. However, directly interacting with a dog resulted in greater declines in anxiety and improved mood scores, more so than watching a video. Consequently, it appears there are psychological benefits to be gained by students from interacting with dogs and it is hoped this study will help to inform future best practices in designing student dog interventions.
... For example, if the therapy dog intervention participant was excited to have the therapy dog present, blood pressure and heart rate may have increased. That said, some therapy dog specific studies have found a change in both [20,106,107]. ...
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Context Pain is a primary reason individuals attend an Emergency Department (ED), and its management is a concern. Objectives Change in symptoms and physiologic variables at 3 time points pre-post a ten-minute St. John Ambulance therapy dog team visit compared to no visit in ED patients who experienced pain. Design, setting and participants Using a controlled clinical trial design, pain, anxiety, depression and well-being were measured with the Edmonton Symptom Assessment System (revised version) (ESAS-r) 11-point rating scales before, immediately after, and 20 minutes post- therapy dog team visit with Royal University Hospital ED patients participating in the study (n = 97). Blood pressure and heart rate were recorded at the time points. Control data was gathered twice (30 minutes apart) for comparison (n = 101). There were no group differences in age, gender or ethnicity among the control and intervention groups (respectively mean age 59.5/57.2, ethnicity 77.2% Caucasian/87.6%, female 43.6% /39.2%, male 56.4%/60.8%,). Intervention 10 minute therapy dog team visit in addition to usual care. Main outcome measures Change in reported pain from pre and post therapy dog team visit and comparison with a control group. Results A two-way ANOVA was conducted to compare group effects. Significant pre- post-intervention differences were noted in pain for the intervention (mean change int. = -0.9, SD = 2.05, p = .004, 95% confidence interval [CI] = [0.42, 1.32], η p ² = 04) but not the control group. Anxiety (mean change int. = -1.13, SD = 2.80, p = .005, 95% CI = [0.56, 1.64], η p ² = .04), depression (mean change int. = -0.72, SD = 1.71, p = .002, 95% CI = [0.39, 1.11], ηp ² = .047), and well-being ratings (mean change int. = -0.87, SD = 1.84, p < .001, 95% CI = [0.49, 1.25], ηp ² = .07) similarly improved for the intervention group only. There were no pre-post intervention differences in blood pressure or heart rate for either group. Strong responders to the intervention (i.e. >50% reduction) were observed for pain (43%), anxiety (48%), depression (46%), and well-being (41%). Conclusions Clinically significant changes in pain as well as significant changes in anxiety, depression and well-being were observed in the therapy dog intervention compared to control. The findings of this novel study contribute important knowledge towards the potential value of ED therapy dogs to affect patients’ experience of pain, and related measures of anxiety, depression and well-being. Trial registration This controlled clinical trial is registered with, registration number NCT04727749 .
... In regard to the use of Animal-Assisted Therapies (AAT) with university veterinary students and university owned donkeys, little is known whether the student-donkey interactions can provide social support and an avenue for initiating new social relationships as well as potentially reducing stress and anxiety in students (22)(23)(24). In addition, student-donkey interactions may support animal welfare and husbandry practices while extending the role of donkeys as pets and companion animals beyond general use in agriculture, recreation, and teaching and learning in veterinary programs (25)(26)(27)(28). ...
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There has been an increased interest in evaluating human–animal interactions and assessing the mutual health and wellbeing. In this study, first-year female and male veterinary school students not paired (n = 58) or paired (n = 25) with immature (≤9 mo) donkeys (n = 13) were engaged in three different types of interactions (1st, hands-off remote learning, 2nd, hands-on passive learning, and 3rd, hands-on active learning) for 30 min each during Week 2 (Time 1), Weeks 5–8 (Time 2), and Week 12 (Time 3) over three, 15-week periods. Student psychological data involved the Penn State Worry Questionnaire (PSWQ) scores collected from the interactive (student-donkey pairs) and non-interactive (no student-donkey pairs) groups and modified Comfort from Companion Animals Scale (CCAS) scores collected from the interactive group during Times 1, 2, and 3. Donkey physiological data involved collection of saliva within 10 min pre- and post-interaction during Times 1, 2, and 3 in association with the different types of interactions for immunoanalysis of cortisol. There were no significant effects of the various times and types of interactions on CCAS scores. While there were no significant effects of group and types of interactions on PSWQ scores, there was an effect (P = 0.01) of time. Overall mean PSWQ scores were significantly lower during Week 12 versus Week 2. Correspondingly, while there were no effects pre- vs. post-interaction within or among times on saliva cortisol concentrations in donkeys, there was an effect (P = 0.02) of the type of interaction. Mean concentrations were significantly lower with the hands-on passive and hands-on active learning versus the hands-off remote learning. In conclusion, while this study provides preliminary evidence surrounding student donkey interactions, future studies are required with more comprehensive designs to clarify these benefits and better understand the advantages and challenges surrounding student-donkey interactions.
... The association between anxiety and patting and stroking the dog-but not with any other pain coping strategy involving the dog-is in line with accumulated experimental evidence reporting anxiety reducing effects of tactile interacting with dogs [60][61][62][63]. Such effects are likely to result from activation of the oxytocin system via pleasant tactile stimulation (for a thorough discussion regarding the role of oxytocin in the psychophysiological effects of human-animal interactions see Beetz et al. [64]). ...
Objective: This study explored the role of companion dogs for psychological adjustment to pain in patients with fibromyalgia with different levels of social support. It also considered the potential moderating effects of the quality of the owner-dog relationship and the use of interactions with dogs as a coping strategy. Setting: A cross-sectional approach was followed using an online questionnaire. Subjects and methods: Linear regression analyses were performed on data obtained from 106 participants (dog owners and non-owners). Sub-analyses were performed on 64 dog owners. Results: Complex associations were observed between human social support, dog ownership and anxiety/depression levels. For participants with low levels of social support, owning a dog was associated with higher levels of anxiety and depression. In contrast, for moderate and high levels of social support, owning a dog was associated with lower levels of anxiety and depression. Sub-analyses showed that participants in this study actively used interactions with companion dogs to manage their pain more frequently than other pain coping strategies. Among those interactions, patting and stroking the dog to cope with pain was associated with lower anxiety levels, even after adjusting for social support. Emotional closeness with the dog was associated with lower depression levels. Conclusions: Obtained results highlight the importance to go beyond mere ownership when addressing the effects of companion dogs and suggest that the development of emotional ties with companion dogs and the active use of interactions with these animals to cope with pain may contribute to better psychological adjustment in patients with fibromyalgia, regardless of human social support.
... Overall, most of the studies supported that pet dogs could be served as buffers against perceived stress [17,25,[20][21]23] and cardiovascular response to stress [25,18,26]. However, in the absence of dogs, some dog owners showed higher level of perceived stress [23 -26]. ...
... However, some evidence of this was visible, such as the high interest in the program from both faculty members and students in participating in a DAI program, because all faculties questioned cooperated and 70.47 percent (148 of 210) of students wanted to participate. Neither sociodemographic variables included in this study showed any kind of effect on the results (Demello, 1999;Somerville et al., 2008). ...
Purpose Dog-assisted interventions (DAIs) are conducted by universities around the world as innovative methods that improve students’ quality of life. The purpose of this paper is to assess the DAI program’s effect on the stress levels, well-being and social skills of first-year students from different degree programs at Complutense University of Madrid (UCM). Design/methodology/approach The study was conducted with 64 first-year students ( M =19.20, SD=1.57). The intervention consisted of three weekly sessions of 1-h duration interacting with a therapy dog. The investigation followed a quasi-experimental pre-test/post-test design with measures of attitudes toward DAI, perceived stress, well-being and social skills. Findings The results indicated significant improvements in all studied variables. Research limitations/implications This study presents some limitations. In the design, the authors lack a control group. Another limitation is related to the sample, which was small. The authors also acknowledge that only one measure of each outcome variable was administered. Likewise, during the interventions, external observations should be added that generate qualitative records focused on student–dog interactions. In addition, physiological measures of stress, such as cortisol levels, should be included in the analysis to further support the obtained results. Nevertheless, as this was a pilot study, future investigations should aim to create a program using a larger sample of both participants as well as and dogs, with a linear/longitudinal design to measure both the mid- and long-term effects. Practical implications In addition, this pilot study was implemented to assist in the validation and adjustment of the DAI program for UCM students. Social implications By using a DAI program, college students have had the opportunity to reduce their stress and develop their social skills, as well as improve their quality of life as individuals and students. Although the implementation of Compludog was small, it was also promising as a pedagogical practice at UCM. Originality/value It was applied for the first time in a Spanish university and provided access to therapy dogs within this context.
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The presence of and request for assistance, service, and support animals has skyrocketed on college campuses in recent years. The purpose of this literature review is to explore potential benefits in the utilization of assistance animals within higher education, especially as it concerns disability service offices. It begins with an overview of the dilemma of increased use of animals with limited shared knowledge base on the benefits of that use and the myriad of terms that are used to describe the therapeutic use of animals. It reviews relevant meta-analyses, moves to a focus of assistance animals in educational settings, especially with college students, highlighting the limited available information on the use of animals by university offices, especially the disability service office. Strength of the research in this literature review is limited due to narrow research availability , small sample sizes, qualitative methods employed in some of the studies, and the limited connections specifically to the dilemmas faced by disability offices in their decision-making about therapeutic animals. This paper concludes with recommendations for future research and for practitioners in disability service offices and related areas.
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While pet ownership may confer physical and psychological health benefits, existing research presents inconsistent findings, and the psychological mechanisms through which health benefits might be conferred are unknown. Exploring human–pet relationships from the perspectives of Bowlby’s attachment theory, namely “attachment-related anxiety” and “attachment-related avoidance,” and Rogers’ core conditions including “unconditional positive regard” and “empathy” may highlight the psychological mechanisms involved. This study compared quality of life (QOL) and psychopathology in pet owners with those without pets. In the pet owners, we additionally assessed pet attachment, and perceived empathy, unconditionality, and congruence in the human–pet relationships. We then compared the relative value of Bowlby’s attachment versus Rogers’ core conditions in human– pet relationships as predictors of wellbeing in pet owners. Overall, pet owners and non-pet owners did not significantly differ in terms of QOL or psychopathology. However, in pet owners, secure pet attachments were associated with lower psychological distress and psychopathology, and those perceiving higher levels of Rogers’ core conditions from their pets had higher QOL. Bowlby’s pet attachment insecurity predicted psychological distress and psychopathology, while Rogers’ total core conditions in pets were significantly predictive of QOL of owners. Differences in wellbeing may not be reliably discernable between pet owners and non-pet owners, as wellbeing is related not to pet ownership alone but to qualities of individual human–pet relationships. The results provide new information about psychological mechanisms through which human–pet interactions are conferred, and support for the applicability of both Bowlby’s and Rogers’ concepts.
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A 10-month prospective study was carried out which examined changes in behaviour and health status in 71 adult subjects following the acquisition of a new pet (either dogs or cats). A group of 26 subjects without pets served as a comparison over the same period. Both pet-owning groups reported a highly significant reduction in minor health problems during the first month following pet acquisition, and this effect was sustained in dog owners through to 10 months. The pet-acquiring groups also showed improvements in their scores on the 30-item General Health Questionnaire over the first 6 months and, in dog owners, this improvement was maintained until 10 months. In addition, dog owners took considerably more physical exercise while walking their dogs than the other two groups, and this effect continued throughout the period of study. The group without pets exhibited no statistically significant changes in health or behaviour, apart from a small increase in recreational walking. The results provide evidence that pet acquisition may have positive effects on human health and behaviour, and that in some cases these effects are relatively long term.
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Autonomic responses were measured while 45 adult women performed a standard experimental stress task in the laboratory with only the experimenter present and 2 weeks later at home in the presence of a female friend, pet dog, or neither. Results demonstrated that autonomic reactivity was moderated by the presence of a companion, the nature of whom was critical to the size and direction of the effect. Ss in the friend condition exhibited higher physiological reactivity and poorer performance than subjects in the control and pet conditions. Ss in the pet condition showed less physiological reactivity during stressful tasks than Ss in the other conditions. The results are interpreted in terms of the degree to which friends and pets are perceived as evaluative during stressful task performance. Physiological reactivity was consistent across the laboratory and field settings.
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The findings of this study confirm the independent importance of social factors in the determination of health status. Social data obtained during patients' hospitalization can be valuable in discriminating 1-year survivors. These social data can add to the prognostic discrimination beyond the effects of the well-known physiological predictors. More information is needed about all forms of human companionship and disease. Thus, it is important that future investigations of prognosis in various disease states include measures of the patient's social and psychological status with measures of disease severity. The phenomenon of pet ownership and the potential value of pets as a source of companionship activity or attention deserved more careful attention that that recorded in the literature. Almost half of the homes in the United States have some kind of pet. Yet, to our knowledge, no previous studies have included pet ownership among the social variables examined to explain disease distribution. Little cost is incurred by the inclusion of pet ownership in such studies, and it is certainly by the importance of pets in the lives of people today and the long history of association between human beings and companion animals. The existence of pets as important household members should be considered by those who are responsible for medical treatment. The need to care for a pet or to arrange for its care may delay hospitalization; it may also be a source of concern for patients who are hospitalized. Recognition of this concern by physicians, nurses, and social workers may alleviate emotional stress among such patients. The therapeutic uses of pets have been considered for patients hospitalized with mental illnesses and the elderly. The authors suggest that patients with coronary heart disease should also be included in this consideration. Large numbers of older patients with coronary heart disease are socially isolated and lonely. While it is not yet possible to conclude that pet ownership is beneficial to these patients, pets are an easily attainable source of psychological comfort with relatively few risks.
The effect of the presence of a friendly animal on children's blood pressures and heart rates while resting and their cardiovascular responses to verbalization were examined. The presence of the dog resulted in lower blood pressures both while the children (N = 38) were resting and while they were reading. The effect of the presence of the dog was greater when the dog was present initially than when it was introduced in the second half of the experiment. We speculate that the animal causes the children to modify their perceptions of the experimental situation and the experimenter by making both less threatening and more friendly. This study provides insight into the use of pets as adjuncts in psychotherapy. (C) Williams & Wilkins 1983. All Rights Reserved.
The physician utilization behavior of 938 Medicare enrollees in a health maintenance organization was prospectively followed for 1 year. With demographic characteristics and health status at baseline controlled for, respondents who owned pets reported fewer doctor contacts over the 1-year period than respondents who did not own pets. Furthermore, pets seemed to help their owners in times of stress. The accumulation of prebaseline stressful life events was associated with increased doctor contacts during the study year for respondents without pets. This relationship did not emerge for pet owners. Owners of dogs, in particular, were buffered from the impact of stressful life events on physician utilization. Additional analyses showed that dog owners in comparison to owners of other pets spent more time with their pets and felt that their pets were more important to them. Thus, dogs more than other pets provided their owners with companionship and an object of attachment.
Recent research on human-dog interactions showed that talking to and petting a dog are accompanied by lower blood pressure (BP) in the person than human conversation. To clarify whether cognition, conditioning, or tactual contact exerted the major influence in this so-called "pet effect," 60 male and female undergraduates with either positive or neutral attitudes toward dogs interacted with a dog tactually, verbally, and visually while BP and heart rate were recorded automatically. Results revealed that (a) subjects' BP levels were lowest during dog petting, higher while talking to the dog, and highest while talking to the experimenter and (b) subjects' heart rates were lower while talking or touching the dog and higher while both touching and talking to the dog. Touch appeared to be major component of the pet effect, while cognitive factors contributed to a lesser degree. Implications for coping with hypertension are discussed, and suggestions for further research are stated.
The effect of a pet on cardiovascular responses of college students was examined under three test conditions (i.e., reading aloud, reading quietly, and interacting with an unknown dog). A repeated-measures analysis with three covariates was used to examine the effect of the treatment on each of six dependent variables (systolic blood pressure, diastolic blood pressure, mean arterial pressure, heart rate, and State and Trait Anxiety). Reading aloud differed from baseline measures under all treatment conditions (p less than .001) Reading quietly and interacting with a pet were slightly below baseline for all dependent variables with a slightly greater effect by reading quietly than interacting with a pet. Examination of interactions between variables revealed no significant differences. Effects on State anxiety level mirrored cardiovascular responses (p less than .001). Trait anxiety levels remained relatively constant throughout the treatments. Results indicated that interacting with a pet does affect physiological and psychological responses by lowering response levels. A parallel effect was also demonstrated by reading quietly. Given the effect of pet interaction upon selected indicators of health in well college students, these data suggest the relevance of examining this treatment with an "at-risk" group.
Blood pressure, heart rate, and respiratory rate were recorded in 24 subjects during 3 9-minute measurement sessions in which they petted an unknown dog, petted a dog with whom a companion bond had been established, or read quietly. Based on the findings of this study, several conclusions were drawn: (1) There is a significant difference in changes over time in both systolic and diastolic blood pressure between petting a dog with whom a companion bond has been established and petting a dog with whom no bond exists; (2) the decreases in both systolic and diastolic blood pressure that occur during petting a dog with whom a companion bond has been established parallel the relaxation effect of quiet reading; and (3) there is a " greeting response" to the entry of a dog with whom a companion bond has been established, which results in significantly higher systolic and diastolic pressures than the response either to an unknown dog or to reading.
Social support and pet ownership, a nonhuman form of social support, have both been associated with increased coronary artery disease survival. The independent effects of pet ownership, social support, disease severity, and other psychosocial factors on 1-year survival after acute myocardial infarction are examined prospectively. The Cardiac Arrhythmia Suppression Trial provided physiologic data on a group of post-myocardial infarction patients with asymptomatic ventricular arrhythmias. An ancillary study provided psychosocial data, including pet ownership, social support, recent life events, future life events, anxiety, depression, coronary prone behavior, and expression of anger. Subjects (n = 424) were randomly selected from patients attending participating Cardiac Arrhythmia Suppression Trial sites and completed baseline psychosocial questionnaires. One year survival data were obtained from 369 patients (87%), of whom 112 (30.4%) owned pets and 20 (5.4%) died. Logistic regression indicates that high social support (p < 0.068) and owning a pet (p = 0.085) tend to predict survival independent of physiologic severity and demographic and other psychosocial factors. Dog owners (n = 87, 1 died) are significantly less likely to die within 1 year than those who did not own dogs (n = 282, 19 died; p < 0.05); amount of social support is also an independent predictor of survival (p = 0.065). Both pet ownership and social support are significant predictors of survival, independent of the effects of the other psychosocial factors and physiologic status. These data confirm and extend previous findings relating pet ownership and social support to survival among patients with coronary artery disease.