DOI: 10.5061/dryad.9cnp5hqdz
title: Changes in human health parameters associated with an immersive exhibit experience at a zoological institution

description: Zoological institutions often use immersive, naturalistic exhibits to
 create an inclusive atmosphere that is inviting for visitors while
 providing for the welfare of animals in their collections. In this study,
 we investigated physiological changes in salivary cortisol and blood
 pressure, as well as psychological changes among visitors before and after
 a walk through the River’s Edge, an immersive, naturalistic exhibit at the
 Saint Louis Zoo. Study participants had a significant reduction in
 salivary cortisol and blood pressure after walking through the exhibit.
 Psychological assessments of mood found that most visitors felt happier,
 more energized, and less tense after the visit. Additionally, participants
 who spent more time in River’s Edge, had visited River’s Edge prior to the
 study, and had seen more exhibits at the Zoo prior to entering River’s
 Edge experienced greater psychological and/or physiological benefits. We
 conclude that immersive, naturalistic exhibits in zoos can elicit positive
 changes in physiological and psychological measures of health and
 well-being and argue for a greater scientific focus on the role of zoos
 and other green spaces in human health.
description: After giving informed
 consent, each participant completed a pre-visit questionnaire form. The
 included the following questions: first visit to River’s Edge (Yes or No),
 age, parking experience rating (scale from 1 to 10, where 1 is “poor” and
 10 is “excellent”), number of exhibits seen prior to River’s Edge, and
 time of arrival at the Zoo. Each participant then answered the pre-UMACL,
 which included 24 mood adjectives, with eight corresponding adjectives to
 each of the three dimensions. Regarding the UMACL,
 participants marked how each adjective reflected his or her current mood
 using a four-point scale (1 = “definitely not,” 2 = “slightly not,” 3 =
 “slightly,” 4 = “definitely”). Within each set of eight adjectives, four
 represented the positive end of each dimension and four the negative end
 (Table 1). Responses for adjectives negatively related to each dimension
 were reversed, and sub scores for each dimension were obtained by summing
 the responses for each adjective. After completing all forms,
 we then collected physiological data. Prior to saliva collection, each
 participant rinsed their mouth with water (supplied by the researcher) and
 placed a SalivaBio Oral Swab (Item # 5001.02, Salimetrics, State College,
 PA) under their tongue for two minutes (as specified by the manufacturer),
 while sitting quietly. After two minutes, the swab was inserted into a
 Saliva Storage Tube (Item # 5001.05, Salimetrics, State College, PA),
 either directly by the participant or by the researcher without direct
 contact. After collection, saliva samples were placed in a cooler on ice
 packs for no longer than two hours, and then brought to the lab for
 processing. Next, a trained researcher took the participant’s blood
 pressure using an OMRON M6 AC (HEM-7322-E) upper arm blood pressure
 monitor in accordance with the IRB-approved protocol. The American Heart
 Association recommends a five-minute rest period prior to blood pressure
 collection to normalize pressure. By having participants fill out forms
 and complete cortisol collection prior to taking their blood pressure, we
 ensured that participants fulfilled their five-minute rest period.
 Additionally, we asked participants to sit quietly without their cell
 phones for two minutes after cortisol collection, averaging a total of
 seven minutes resting time. Per manufacturer directions, blood pressure
 was recorded using the participant’s left arm placed flat on a table with
 both feet flat on the ground. Prior to the study, all researchers were
 given formal training by Zoo medics on using the OMRON M6 AC
 (HEM-7322-E). Finally, we asked participants to wear a colorful lanyard to
 identify themselves to the researchers at the end of the exhibit trail.
 Participants were also instructed not to consume any food or drinks (other
 than the boxed water provided) and refrain from chewing gum during their
 walk through the exhibit. We invited participants to enjoy their time in
 River’s Edge at their normal pace without any time restrictions. Once the
 participant finished walking through River’s Edge, they performed a
 similar suite of tests, including measurement of blood pressure and
 collection of saliva samples, and a post-visit questionnaire. This had the
 following questions: gender (as identified by the participant), party
 size, number of kids in party under 14 years old, incidence of having a
 staff interaction, animal that they found most engaging (if any), whether
 they had a close up encounter with that animal, and looked into the
 animal’s eyes. Each participant then answered the post-UMACL. The same version of the
 UMACL was used pre- and post-River’s Edge experience. A
 researcher timed and recorded each step in the data collection process.
 The total number of minutes spent in River’s Edge was calculated, total
 number of minutes spent in the Zoo prior to entering River’s Edge and
 outside air temperature during River’s Edge was recorded for each
 participant. Daily Zoo attendance was included as an additional variable.
 This study was approved by Heartland Institutional Review Board (IRB) and
 all principal investigators completed the Collaborative Institutional
 Training Initiative (CITI) IRB training. The study was deemed expedited
 with written consent. Inferential statistical
 analyses were performed in SAS® Studio 3.7 (SAS Institute Inc., Cary, NC,
 USA). Prior to analysis, study participants were assigned to two blocks
 based on the time of day they entered River’s Edge (prior to 12:30 PM vs.
 after 12:30 PM), controlling for effect of time of day on the response
 variables measured. The effects of possibly associated factors on systolic
 and diastolic blood pressure, salivary cortisol concentrations, TA, EA,
 and HT were all evaluated using a generalized linear mixed model within
 the MIXED procedure. Fixed categorical factors included time (pre or post
 River’s Edge experience), gender (male or female), first visit to River’s
 Edge (yes or no), found the elephants the most engaging (yes or no), had a
 staff interaction (yes or no), had a close up encounter with the animal
 found to be most engaging (yes or no), and looked into this animal’s eyes
 (yes or no). Quantitative variables included air temperature, age, daily
 Zoo attendance, party size, number of kids in party under 14 years old,
 parking experience score, total number of exhibits seen prior to River’s
 Edge, total number of minutes spent at the Zoo prior to River’s Edge, and
 total number of minutes spent in River’s Edge. Individual ID
 and block (described above) were included as random factors, as well as
 the interaction terms between time, and the fixed and quantitative
 factors. Non-significant interaction terms between time and quantitative
 factors were removed to generate a single slope term for the final models.
  All other variables, regardless of statistical significance, were
 included in the final models. Though the design of the study is repeated
 measures in nature, there were only two measurements made within each
 subject, therefore a simple variance component (VC) covariance structure
 was used.