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Research Supporting Animal/Nature Assisted Therapy

The Biophilia Connection
by Linda Nebbe

The biologically based, inherent human need to affiliate with life and life like processes. . . 
That human identity and personal fulfillment are dependent on the human relationship to nature. . . 
Essential for emotional, cognitive, aesthetic, and spiritual development.

The degradation of this human dependence on nature brings the increased likelihood of a deprived and 
diminished existence — again, not just materially, but also in a wide variety of affective, 
cognitive, and evaluative respects (Kellert & Wilson, 1995, pp42-43) 

Although old as the first man and animal on earth, the birth of the fields of animal-assisted (AAT) and nature-assisted therapy (NAT) are marked by the end of WWII with the transformation of war time programs to civil programs. These programs included unemployed war dogs trained as guide dogs, gardening programs provided for veterans evolving into horticulture therapy, and a sailor training program in England moving to the United States and becoming Outward Bound (Nebbe, 1995). AAT might also be marked by the publication of two books on children and animals by Boris Levinson, a psychologist who worked with a canine partner, Jingles (Nebbe, 1995). Following shortly was the 1978 founding of the Delta Society, a professional organization dedicated to research and education in this new field (Nebbe, 1995). 

Research in AAT followed the 1978 creation of a professional identity with the Delta Society.  Multiple origins of research contributed to the validation of NAT. The first research was outcome based. Examples of the early research in Animal-Assisted Therapy (AAT) include:

  • Interaction with animals may enhance an individuals self- esteem or self worth (Tomaszewski, Jenkins,Rae, & Keller, 2001; Walsh &  Mertin, 1994).
  • Presence of animals can impact mood positively (Kaminski, 2002; Lutwackk-Bloorm, Wijewickrama, & Smith, 2005). 
  • Individuals who stutter find relief when talking to a dog (Davis, 1985).
  • Animals can enable children develop the abity to empathize (Bryant, 1986, Malcarne, 1986).
  • Animals can be effective in alleviating depression (Folse, Minder, Aaycock, & Santana, 1994).
  • The company of animals can lower blood pressure and heart rate (Friedmann, Katcher,  Thomas, Lynch, & Messent, 1983).
  • Animals can have a positive effect on human health and behavior ((Friedmann, E., Katcher, A., , Thomas, S., Lynch, J., & Messent, P., 1980; Friedman, E., Katcher, A.,  Thomas, S.,  Lynch, J., & Messent, P., 1983; Serpell, 1991)).
  • Pets can alleviate loneliness (Banks, 2002).
  • The presence of a dog improves the learning environment for children (Ozawa. Ohtani, & Ohta, 2010.)
  • The effects of AAT can lessen anxiety (Barker & Dawson, 1998).
  • The presence of animals stimulates attendance and participation (Beck, Seraydarian, & Hunter, 1986).
  • The presence of animals increases social interaction (Bernstein, Friedmann,& Malaspina, 2000; Fiek, 1993).
  • The presence of animals helps to establish rapport (Gonski, Peacock, & Ruckert, 1986).
  • Research has strongly supported and explained the positive influence of the human/nature connection. Following are a few of the studies involving people with nature:
    • When in the hospital, individuals with a room with a view on a court yard instead of a garbage dump or wall will shorter hospital stays, take less pain medications, and need less nursing care (Ulrich, 1984).
    • Exercising in a rural area will be more beneficial (lower heart rate, blood pressure, stress reduction) than exercise in a urban area or gym (Hartig, Mang, & Evans, 1991)
    • There is a dramatic reduction in myopia or nearsightedness in children who spend time outdoors. (Rose, et al., 2008).
    • Americans who live in areas that lost thousands of trees to insects and other kills saw 15,000 deaths from cardiovascular diseases and 6,000 more from respiratory illness compared to people who lived in areas that had trees. (Lehman, S. 2013)

      However, recently, new research strongly supports not just the benefits of the animal/nature/human connection, but emphasizes that 
      this connection is essential for mental and physical health.

Important more recent research includes:

  • Circadian rhythms refers to the internal “clock” of every living being which is turned toto the natural clock of the universe (day and night, seasons, tides, and year among others) This universal clock impacts the function and processes of our bodies. (Ackerman, 2007). Specifically we think of sleep cycles, but every organ is impacted including physiological factors underlying obesity, high cholesterol and metabolic-based biseases like diabetes. (Eckel-Mahan, Patel, Mohney, Vignola, Baldi, and Sassone-Corsi, 2012)
  • Hygiene Hypothesis refers to a lack of early childhood exposure to infectious agents (microorganisms and parasites) found in the natural environment and in animals (Chen, et. al., 2008). When exposed an individual’s immune system begins to produce antibodies that are then present to protect the individual throughout their life. Respiratory problems are linked to this phenomenon. In other words, playing in the dirt is an important developmental task of childhood. Children who have multiple family pets and children who play outdoors have fewer allergies and respiratory diseases than children who don’t (Rook & Lowry, 2008) . Growing up on a farm has been proven to directly affect regulation of the immune system and limit Se
  • Vitamin D from the sun does not just build strong bones. Three out of four Americans have a deficient level of Vitamin D! Vitamin D contributes to regulation of blood pressure and heart rate, strong muscles, and processes of many other organs. (Neighmond, 2009) In addition there is “blue light” in sun light, not found in our lighting systems. Blue light impacts areas of the brain that involve attention and memory and modulates wake and sleep cycles (Selhub & Logan, 2012)
  • Bacteria in the soil stimulate the neurotransmitter, serotonin, which impacts our neurological system and is believed to have antidepressant qualities. Serotonin is also believed to be important in controlling obesity and anxiety (Lowrey, C. 2007). Exposure to specific bacteria in the environment also has been found to increase learning behavior (American Society for Microbiology, 2010).
  • Negative ions The air around us also impacts our brain and well being. Negative ions in the air we breath are odorless, tasteless, and invisible molecules we inhale in certain environments (mountains, waterfalls, beaches) that produce biochemical reactions which increase blood flow to the brain and increase serotonin which helps to alleviate depression, relieve stress, boost energy, increase alertness, improve metabolism, and enhance mood.  The effect is best on clear, calm days with low humidity early in the morning (sunrise) and late evening (WebMD, 04/6/02, Selhub & Logan, 2012) 
  • Positive ionsPositive ionization has a negative affect on mood causing tiredness and lethargy, aches and pains, and illness. Low Negative ionization or positive ionization is found indoors, particularly in rooms with electrical equipment, chemicals, lack of ventilation, or in polluted environments (EMR Labs, 1996)
  • The mammalian hormone oxytocin is produced when a female mammal has a baby. Feeding, holding close, nurturing, speaking “motheresse” stimulate this hormone in parents and infants leading to bonding. The hormone in turn influences other body chemicals causing lower blood pressure, lower heart rate (relaxation response), feeling of compassion and connection. In fact the whole immune system is enhanced. Oxytocin is also considered the “anti-stress” hormone that helps us enjoy life and makes love and relationships possible (www.olytocin.com 2012) . Oxytocin is also produced during other life experiences like falling in love or when we pet a dog, nurture an animal (Miller, Kennedy, DeVoe, Hickey, Nelsonn, Kogan, 2009), and we believe could also occur when we dig in our gardens and nurture our yards (Olmert, 2009).
  • Oxytocin may be at the root of the human development of compassion, but compassion can be developed. It appears the more that compassion is practiced (meditation and practice) the more prevalent it becomes part of an individual’s behaviors. Compassionate feelings and acts also impact human physical and mental health in many positive ways (Goleman, 2003)

Despite the noted benefits and research findings, people are going outdoors less and less. Richard Louv in his book Last Child in the Woods explores how this phenomenon affects our children He points out we have become a much more sedentary society. The average child from 6 to 11 years spends about 30 hours a week in front of a TV or computer monitor. Most of the outdoor and physical experience they have are through media, a one dimensional experiences happening through only their eyes. An indirect affect of this behavior is a decline in human touch/contact. The amount of space children travel outside the home has diminished by over 90% since 1970. Senses as well as knowledge are becoming dull. Louv refers to it as the “rise of cultural Autism”. Louv attributes this dramatic change to reduced leisure time, more demands on children from structured activities, and an increased emphasis on study and homework. School curriculums have excluded recess and added extra classes after school. Games have replaced play, with an emphasis on organized sports. Children are restricted from the few natural environment play areas by building codes, government protection of fragile environments, rules keeping travelers on trails, lack of investment in natural play environments because of lack of economic gain, and fear they might get hurt! An irrational fear, Louv says, since as many dangers lurk inside.

And what about adults? The news is the same. An article from WebMD says typical American spends up to 25% less time in nature than in 1987, and time spent in nature dropped by about compensate, to bring nature, the natural world, inside (DuBos, 1972),


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