Sourced from GOOD NATURE: Why seeing, smelling, hearing and touching plants is good for our health by Kathy Willis with permission from Pegasus Books. Copyright © 2024 by Kathy Willis.
Recently I walked through the Botanical Garden in Oxford. This beautiful and historic location, right in the heart of the city, attracts more than 200,000 visitors every year because of its peaceful walking paths and relaxing views. But it wasn’t just the elegant variety of plants, or even the impressive scope of scientific research that was done. undertaken here, caught my attention. It was a little child who reached out to touch the petal of a rose, and her grandmother, instead of telling her not to touch it, stroked the silky petal against her cheek. The child was intrigued and delighted.
We are often told, ‘Don’t Touch’ and ‘Keep your hands off the grass’. Maybe it’s time to ditch those outdated views. Perhaps experiencing nature through tactile interaction with leaves, bark and petals is good for us. Maybe Grandma was right.
We have had the urge to touch things from a very young age. Take a toddler to a store and all he has to do is touch everything he sees. This is because we use touch to learn. But is there a deeper meaning in our response to how nature feels, looks, sounds and smells?
A few years ago, the idea of allowing animals into hospital wards, nursing homes and pediatric vaccination clinics would have been unthinkable. The risk of contamination would be considered too great. Times have changed. When I recently visited an elderly relative in a nursing home, the room was full of dogs being petted by the residents. It was clear from both the faces of the seniors and the wagging tails of the dogs that there was a shared ‘love-in’. The happiness and mental well-being that petting these dogs brought to residents was clear to see – and it also made it clear to me why it is becoming increasingly common to see therapy dogs in clinical settings. The positive emotions and reduced fear and anxiety that occur from touching and petting these dogs are now often considered to outweigh the risks associated with their potential biological hazard.
Interestingly, these studies also show that individuals who have more physical contact with the dogs during these interactions exhibit lower levels of stress afterwards, suggesting that it may be this element of tactile stimulation (touch) that provides the benefits that we usually associate with being. around animals.
But does the same work with inanimate nature? Can we derive similar benefits from touching leaves, caressing the bark of trees, or even the wood of trees, plant material that has long been dead?
Many of us certainly seem to have an instinctive desire, or even need, to stroke the surfaces of wooden furniture – as beautifully illustrated in a conversation I had with Barnaby Scott, a local furniture maker in Oxfordshire who founded the company Waywood:
When people see my furniture, the first thing they ask is if they can touch it. They are timid, but we are all strongly drawn to touching wood and it is comfortingly warm.
And from the conversation it became clear that not only his customers think this way:
Wood provides a warm, comforting environment with beautiful associations from the living environment, which other materials do not do. When the workshop was asked to cut through some plastic fence rails, we couldn’t wait to throw them away and return to our woods – the difference was palpable for everyone.
But what actually happens to us when we touch and stroke plant material? Does it evoke some of the same physiological and psychological calming mechanisms that occur when we pet and touch certain animals? Should we hug trees in the park with the same lack of self-consciousness with which we pet our neighbor’s cat? It has long been known that gardening is associated with many positive health benefits for young and old. Horticultural therapy is now a well-recognized occupational health intervention for people with mental health conditions such as depression and memory loss, especially the elderly. It has also been shown to be effective in reducing some of the chronic symptoms in patients with schizophrenia, and reducing stress levels and agitation in children with ADHD and autism. It is often assumed that ‘being outdoors’ is enough because it provides the combined benefits of sound, sight, smell, exercise and social interaction. This is probably correct – it’s a combination of all of them. But what specific role does touch play in this? Can we isolate its effects from our other senses? For example, therapeutic animal petting sessions often take place indoors without the added environmental stimuli of nature’s smells and sounds or increased exercise. Are there specific changes that are activated in our bodies when we touch plants?
An intriguing experiment that started me on this journey of wondering if touching plants affects our physical and mental well-being was an experiment where participants sat in a clinical setting with their eyes closed and were asked to touch four different materials : a leaf of a living pothos plant (Epipremnum aureumwhich we have already met under the alternative name: devil’s ivy); an artificial pothos leaf made of resin; a piece of soft fabric; and a metal plate. While doing this, they had their brains scanned using infrared spectroscopy to detect changes in cerebral blood flow and therefore central nervous system activity. Clear results emerged: touching the live pothos plant leaf resulted in a significantly calming response compared to touching the other materials. This was a simple experiment with a small number of participants – only fourteen. But for me it raised other questions – not least: how common are these kinds of reactions when we touch and caress plant material, such as the different types of wood or the leaves of a living plant? And which parts of our body should do the touching; Is it just touching with our hands, or do we get a similar reaction when we walk barefoot on grass or wooden floors, for example? These experiences are often part of our daily lives; are they actually doing us any good? Should we actively seek them out?
We all have millions of receptors that respond to different touch stimuli, spread across our skin. However, certain parts of our body – for example our face and hands – have a much higher density of these receptors. This explains why these areas are much more responsive to external physical stimuli, including touch. There are also different types of receptors in our skin, stimulated by mechanical touch (stroking, stretching, vibration), temperature (thermoreceptors) and chemicals (chemoreceptors). Our skin, muscles, joints and most of our internal organs also contain pain receptors (nociceptors) that are activated by actions that potentially damage tissue. When we touch something, these receptors activate and generate signals that travel via sensory nerves to neurons in the spinal cord and to the thalamus area of the brain. The neurons in the thalamus area then transmit signals to other parts of the brain that cause a variety of different responses, including, for example, movement of our limbs, changes in our heart rate, breathing rate, attention, focus and consciousness. This is the practical, physical response to the stimuli provided by the biology of touch.
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