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Journal of Alzheimer’s Disease 55 (2017) 569–574
DOI 10.3233/JAD-160703
IOS Press
569
The Utilization of Robotic Pets
in Dementia Care
Sandra Petersena,∗, Susan Houstonb, Huanying Qinc, Corey Taguedand Jill Studleye
aThe University of Texas at Tyler, College of Nursing and Health Sciences, Tyler, TX, USA
bBaylor Scott and White Health Care System Office of the CNO, Plano, TX, USA
cBaylor Scott and White Health Care System, Dallas, TX, USA
dACH Health Services, Hurst, TX, USA
eBaylor Elder HouseCalls, Dallas, TX, USA
Accepted 18 August 2016
Abstract.
Background: Behavioral problems may affect individuals with dementia, increasing the cost and burden of care. Pet therapy
has been known to be emotionally beneficial for many years. Robotic pets have been shown to have similar positive effects
without the negative aspects of traditional pets. Robotic pet therapy offers an alternative to traditional pet therapy.
Objective: The study rigorously assesses the effectiveness of the PARO robotic pet, an FDA approved biofeedback device,
in treating dementia-related symptoms.
Methods: A randomized block design with repeated measurements guided the study. Before and after measures included
reliable, valid tools such as: RAID, CSDD, GDS, pulse rate, pulse oximetry, and GSR. Participants interacted with the PARO
robotic pet, and the control group received standard activity programs. Five urban secure dementia units comprised the setting.
Results: 61 patients, with 77% females, average 83.4 years in age, were randomized into control and treatment groups.
Compared to the control group, RAID, CSDD, GSR, and pulse oximetry were increased in the treatment group, while pulse
rate, pain medication, and psychoactive medication use were decreased. The changes in GSR, pulse oximetry, and pulse rate
over time were plotted for both groups. The difference between groups was consistent throughout the 12-week study for
pulse oximetry and pulse rate, while GSR had several weeks when changes were similar between groups.
Conclusions: Treatment with the PARO robot decreased stress and anxiety in the treatment group and resulted in reductions
in the use of psychoactive medications and pain medications in elderly clients with dementia.
Keywords: Animal assisted therapy, biofeedback, dementia, psychology, robotics
INTRODUCTION
According to Alzheimer’s Disease International,
the worldwide costs of dementia ($604 billion in US
dollars) amounted to more than 1% of the global gross
domestic product in 2010. The worldwide cost is pro-
jected to reach $1 trillion in 2018. Currently, over 46
million people are living with dementia. By 2050, this
number will have risen to 131.5 million. Furthermore,
∗Correspondence to: Sandra Petersen, DNP, RN, GNP-BC,
FNP-BC, FAANP, Professor and Director,Doctor of Nursing Prac-
tice Program at UT Tyler, College of Nursing & Health Sciences,
3900 University Blvd., Tyler, TX 75799, USA. Tel.: +1 214 213
4726; Fax: +1 866 672 8204; E-mail: spetersen@uttyler.edu.
dementia patients have increased healthcare utiliza-
tion rates compared with patients with other major
diseases. Previous research shows that informal costs
make up a substantial part of the total annual costs
of dementia. In the United States alone, the care pro-
vided by informal caregivers to people with dementia
was valued at more than $202 billion in 2010 [1].
Behavioral and psychological problems affect
most individuals with dementia at some point dur-
ing the progression of the disorder, adding to the
cost and burden of caring for them. For example,
as many as 83% of individuals with dementia suffer
with depression [2]; and as many as 77% suffer from
anxiety [3]. These problems may ultimately result in
ISSN 1387-2877/17/$35.00 © 2017 – IOS Press and the authors. All rights reserved
This article is published online with Open Access and distributed under the terms of the Creative Commons Attribution Non-Commercial License (CC BY-NC 4.0).
570 S. Petersen et al. / The Utilization of Robotic Pets in Dementia Care
long-term hospitalization, increased medication use,
and decreased quality of life for caregivers and
patients.
Despite the fact that animal assisted therapy has
been used for many years, some senior healthcare
settings still do not accept animals, even though they
acknowledge the positive benefits of animal assisted
therapy and activities involving therapy pets. Many
are concerned regarding the negative effects to human
beings such as allergies, infections, biting, scratching,
or even fear of the animals involved in therapy [4].
Consequently, robotic pet therapy is seen as a
viable substitute for animal therapy. The PARO
(short for “personal robot” in the Japanese language)
Robotic Pet has been in use in many countries since
2003. The FDA-approved device is designed to look
like a baby harp seal, which is a non-familiar animal
to most people. As a result, individuals can readily
engage with PARO without preconceptions or expec-
tations. Covered in artificial fur, the robotic creature
has a hard inner skeleton under which there are dual
processors that control software for behavior genera-
tion and voice recognition. PARO, as a result, imitates
animal behavior, but also responds to light, sound
temperature, touch and posture and, over time, due to
its artificial intelligence capability, develops its own
“character.” PARO promotes the therapeutic results of
psychological, physiological, and social effort from
those who interact with it, lowering stress, improving
depression, and reducing anxiety in many cases [5, 6].
Accurate data was needed regarding the effective-
ness of robotic pet therapy. Therefore, the primary
purpose of this study was to rigorously assess the
effectiveness of PARO robotic pet therapy in treat-
ing dementia-related symptoms such as anxiety and
depression.
MATERIALS AND METHODS
A randomized block design with repeated mea-
surements guided the study. The before and after
outcome measures included: Rating for Anxiety in
Dementia (RAID), Cornell Scale for Depression
in Dementia (CSDD), Global Deterioration Scale
(GDS), pulse rate, pulse oximetry, galvanic skin
response (GSR), and medication utilization. The
interventional group received treatment with the
PARO robotic pet three times a week for 20 minutes,
and the control group received the standard of care,
which includes music, physical activity, and mental
stimulation in 20-minute segments.
IRB approval and ethics committee approval
were obtained. Facility letters of support were also
obtained. Education was provided for the facility
nurses and staff regarding the purpose of the study
and the protocols for data collection. Subjects who
met inclusion/exclusion criteria, or their significant
family member, were approached and consented. Par-
ticipation in the study was voluntary, and all residents
had the right to refuse. Subjects routinely participated
in group programming activities throughout the day.
Subject groups were randomly assigned by the toss
of a coin to receive either the PARO robotic pet or
standardized programming.
Both interventional and control group subjects
were volunteers. Each participant was physician-
diagnosed with mild to moderate dementia, utilizing
standard Diagnostic and Statistical Manual (DSM)
or the National Institute on Aging Alzheimer’s
Organization criteria, and was 65 years of age or
older. Patients with pre-existing psychiatric diag-
noses (bipolar, schizophrenia, personality disorder,
etc.) and those unable to participate in programming
due to physical limitations were excluded from par-
ticipating in the study.
Consenting subject groups were randomly-
assigned based on a coin toss until sample size was
obtained. Cohen’sdwas used for sample size calcula-
tion. A sample of 60 was estimated based on an effect
size (0.35) with a power of 0.80, and a 10% rate of
attrition. The participants were equally divided into
study and control groups and each group included 5
subgroups.
Experimental group participants were exposed to
treatment with the PARO robotic pet once a day for
three days a week. Each session lasted 20 minutes and
sessions continued for three months. The PI and the
trained facility nurses conducted the sessions with the
PARO robotic pets in the activity room of the assisted
living memory care units. The 20-minute sessions
involved seating 6 residents at a round table, placing
the PARO robotic pet in the center of the table, and
encouraging the residents to interact with the robotic
pet by demonstrating interaction. The demographic
data and pre-tests of RAID, CSDD, and GDS were
administered by the PI and the trained facility nurses
prior to the sessions with the PARO robotic pet as
well as after three months of exposure. The GSR,
pulse oximeter, and pulse rate were recorded for each
subject for every session throughout the three-month
time period.
The comparison group received what is consid-
ered the facilities’ standard of care which includes
S. Petersen et al. / The Utilization of Robotic Pets in Dementia Care 571
physical activity, music, and mental stimulation.
Facility nurses conducted these activities in small
groups in the activity room on a daily basis. The
demographic data, GDS scores, and pre-tests of
RAID and CSDD were administered and collected
by the PI and the trained facility nurses and staff
prior to the standardized program sessions as well as
after three months of exposure. The GSR, pulse rate,
and pulse oximetry readings were recorded for each
subject before and after every session throughout the
three-month time period.
In summary, pulse oximetry, pulse rate, and GSR
were collected before and after each 20-minute expo-
sure to the robotic pet. The CSDD and the RAID were
utilized for staff observations of selected behaviors
prior to and after the study. Residents were assessed as
to the severity of their dementia with the GDS before
and after the study. Staff observation and measure-
ment of pulse oximetry, pulse rate, and GSR, along
with the assessment of severity of dementia with the
GDS, occurred in the same manner with a control
group of residents, who did not receive treatment with
the PARO robotic pet.
The RAID Scale is a reliable and valid scale for
measuring anxiety in dementia patients. In a previous
study, inter-rater reliability and test/retest reliability
were moderate, with an overall agreement of over
80% for individual items. Scores of 11 and above
on the scale indicated significant clinical anxiety.
The scale correlated significantly with other anxi-
ety scales and with independent ratings [7]. Criterion
validity and construct validity were established when
the instrument was piloted on 51 inpatients and 32
day-hospital patients who had a DSM diagnosis of
dementia.
The sensitivity and specificity of the CSDD has
been reported as the 93% and 97%, respectively. The
CSDD was chosen for this study because its validity
as a screening tool for depression dementia patients
exceeds the Geriatric Depression Scale in progress-
ing dementia [8]. A score >10 indicates a probable
major depressive episode. A score >18 definite major
depressive episode.
Interrater reliability for the GDS was found to be
high, ranging from 0.87 to 0.97 in various studies
[9]. Concurrent validity of the GDS was established
by comparing scores of the GDS to scores from the
Mini-Mental State Examination and showed high cor-
relation between the two tools. Clinical/biological
validity was also demonstrated to be satisfactory by
comparing GDS results with results from psychome-
tric tests (r= 0.30–0.60), CT scan measures (r= 0.50
for sulcal enlargement and 0.60 for ventricular dila-
tion), and cerebral blood flow (r= 0.70–0.80) [10].
Pulse rate and pulse oximetry have long been vali-
dated as indicators of stress and anxiety. As stress or
anxiety decrease, the pulse rate is decreased. Both of
these are autonomic responses that fluctuate regard-
less of cognitive ability. Pulse oximetry readings
improveasstress decreases [11].GSR,or skin conduc-
tivity, can also be used as an indication of one’s state
of arousal [12]. GSR has been observed to continu-
ously change over time and is correlated to the activity
of the eccrine sweat glands. Located in the dermis,
the eccrine sweat glands regulate body temperature
by manufacturing and excreting sweat onto the skin’s
surface. GSR can be measured through the collec-
tion of skin conductance and used as the quantitative
indicator of anxiety [13]. The development of bias
potentials and polarization were minimized through
the use of silver chloride cup electrodes. Velcro fas-
teners were used to secure the electrodes to the volar
surfaces. Retrospective and concurrent data was col-
lected for utilization of pain, depression, sleep and
behavior medications during the course of the study.
RESULTS
A total of 61 patients (23% males, 77% females)
with an average age of 83.4 years were randomized
into the control and treatment groups. Table 1 sum-
marizes the comparison in baseline characteristics
and shows no difference between the two groups,
thus relating homogeneity. Compared to the control
Table 1
Comparison in baseline characteristics, values presented as mean
(std) unless specified. T test used for continuous variables and
Chi-square test for categorical variables
Control (n= 26) Treatment (n= 35) pvalue
Age 83.3 (6.0) 83.5 (5.8) 0.873
Male, n(%) 6 (23.1) 8 (22.9) 0.984
Race, n(%)
Black 0 (0) 2 (5.9) 0.448
Hispanic 1 (3.9) 1 (2.9)
White 25 (96.1) 31 (91.2)
RAID 9.2 (5.5) 12 (6.3) 0.070
GDS 5.3 (1.0) 5.6 (0.8) 0.155
CSDD 9.4 (4.8) 12.5 (6.7) 0.054
GSV 87.5 (5.9) 86.0 (5.9) 0.352
PulseOX 90.3 (17.7) 94.8 (2.1) 0.202
PulseRate 77.5 (9.5) 75.4 (11.1) 0.439
Pain med 6.1 (4.9) 6.9 (7.1) 0.639
Sleep med 3.9 (3.5) 3.8 (3.5) 0.901
Depression med 5.3 (3.6) 5.8 (4.6) 0.648
Behavior med 7.7 (9.7) 9.2 (9.1) 0.537
572 S. Petersen et al. / The Utilization of Robotic Pets in Dementia Care
Table 2
Comparison in outcome changes after therapies, values presented
as mean (stderr). T test was used
Difference (post – pre) Control Treatment pvalue
RAID 0.55 (0.2) 2.5 (0.6) 0.003
GDS –0.06 (0.1) –0.07 (0.03) 0.948
CSDD 0.78 (0.4) 2.81 (0.4) 0.001
GSV 0.99 (0.2) 5.47 (1.3) 0.0005
PulseOx 0.46 (0.1) 1.66 (0.08) 0.0001
PulseRate 0.08 (0.2) –2.97 (0.2) 0.0001
Pain med dose 0.26 (0.5) –2.22 (0.7) 0.005
Sleep med dose 0 (0) 0.03 (0.6) 0.955
Depression med dose 0 (0) –0.68 (0.4) 0.083
Behavior med dose –0.09 (0.09) –2.09 (0.54) 0.0009
group, pulse oximetry and GSV were increased,
while RAID, CSDD, pulse rate, pain medication,
and behavior medication were significantly decreased
in the treatment group. Table 2 displays the aver-
age changes in outcome measures in response to the
therapy. No differences in GDS staging or sleep med-
ication and depression medication utilization were
noted between the two groups. Table 3 contains the
pvalues from multivariable regression representing
the change in each outcome after the therapy. After
adjusting for demographic variables, the group status
showed a significant effect on all outcomes except
GDS, sleep medication and behavior medication.
Table 4 represents a multivariable regression, using
a mixed model, depicting GSV, pulse oximetry, and
pulse rate, which were repeatedly measured through-
out the study. After adjusting for demographics and
time variable, the group status showed a significant
effect on GSV, pulse oximetry, and pulse rate. The
changes in GSV, pulse oximetry, and pulse rate over
time were plotted for both groups in Fig. 1. The differ-
ence between the two groups was seen consistently
throughout the study for pulse oximetry and pulse
rate, while changes in GSV showed no difference
between the two groups for several weeks.
DISCUSSION
Using the data from the three-month study,
researchers found that intervention with the PARO
Table 4
Pvalues from multivariable regression analysis – Mixed Model
Independent Dependent variables as difference
Variable between post- and pre- therapies
GSV PulseOx PulseRate
Age 0.568 0.873 0.384
Gender 0.214 0.616 0.812
Group 0.008 0.0001 0.0001
Week 0.310 0.641 0.072
Day 0.817 0.209 0.564
robotic pet seal provided a viable alternative for
controlling symptoms of anxiety and depression in
elderly patients with dementia, often in lieu of phar-
macological modalities. Oxygen saturation, pulse
rate, GSV, RAID, and CSDD and medication use
were all positively impacted in patients participating
in the interventional group, indicating improvement
in symptom control.
This study significantly contributes to the body of
knowledge regarding robotic biofeedback devices in
the treatment of dementia. The study utilized a robust
sample, measured a variety of outcomes, and used
a randomized design. Previous studies lacked rigor
with regard to sample size, design, and controlling for
extraneous measures. Caution should be utilized in
generalizing results beyond the sample in this study,
however, due to the unique population of subjects.
Implications for practice for providers working
with this population include: 1) the average individ-
ual in the senior living environment consumes on
average 16 to 28 medications per day at an aver-
age cost of 1200 to 1500 U.S. dollars per month
[14]; and, 2) intervention with the PARO robotic
pet three times weekly for 20 minutes significantly
reduced the need for these medications. As the lit-
erature suggests, the use of benzodiazepines in the
elderly population result in falls, sedation, and physi-
cal dependence [15]. Additionally, providers may use
antipsychotics off-label to treat negative behaviors
in individuals with dementia; these medications can
cause or worsen heart arrhythmias in the older adult
and worsen other chronic conditions such as renal
impairment, GI distress, and liver impairment [16].
Use of pain medications in the treatment group was
Table 3
Pvalues from multivariable regression analysis – General Linear Model (GLM)
Independent Variable Dependent variables as difference between post- and pre- therapies
RAID GDS CSDD PainMed SleepMed DepressionMed BehaveMed
Age 0.738 0.699 0.563 0.847 0.549 0.540 0.678
Gender 0.914 0.478 0.401 0.743 0.321 0.356 0.689
Group 0.005 0.912 0.001 0.009 0.910 0.138 0.003
S. Petersen et al. / The Utilization of Robotic Pets in Dementia Care 573
Fig. 1. Profiling of changes in biometric measures over time.
significantly decreased as well, which may lead to
further utilization of the PARO. Other applications
for the PARO, in addition to reducing stress (as mea-
sured by GSV), may include improved oxygenation
and improved cardiac status. The treatment group
improved and maintained improvements in GSV,
pulse oximetry, and pulse-rate over time (Fig. 1).
Whereas depression scores improved with the
treatment groups, providers were reluctant to dis-
continue or reduce the amount of antidepressant
medication. Further research is needed regarding
provider awareness of evidence-based results of non-
traditional methods of treating depression such as
biofeedback therapy with robotic pets and provider
willingness to discontinue or decrease medication use
when depression scores improve with such therapy.
Significant improvements in observed pain and
decreased pain medication use were noted in the
interventional group. Recent literature advises an
observed overlap between pain and psychiatric dis-
orders is common because some neurotransmitters,
such as serotonin and norepinephrine (typically lower
in individuals with dementia), are involved, albeit in
different brain regions, in pain and sensory process-
ing, as well as in modulating mood [17]. Thus, it is
likely that treatment with the PARO, which decreases
stress and anxiety, will also be effective in controlling
or assisting in the relief of chronic pain.
Future research could examine the impact of
biofeedback therapy with robotic pets in acute care
settings with various patient populations. Other
physiological measures could be considered to mea-
sure the impact of interventions with the PARO
robotic pet seal, especially varying exposure of the
treatment regimen.
ACKNOWLEDGMENTS
The authors wish to acknowledge the Baylor
Deerbrook Charitable Trust that funded the study.
Appreciation is also expressed to the leadership,
nurses, staff and families at Signature Senior Liv-
ing of Dallas, Texas and Legend Senior Living of
Wichita, Kansas who took part in the study.
Authors’ disclosures available online (http://j-alz.
com/manuscript-disclosures/16-0703r1).
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