Research in environmental psychology often fascinate me by showing how very sensitive we are. Just by changing some minor details in a room researchers are able to make measurable impacts on our psyche. I think that Alain de Botton (in The Architecture of Happiness) described it best by calling us vulnerable to design. And when are we more vulnerable than when we are in pain?

Would something this small have an impact on you?; photo by AmySelleck

Following studies were inspired by well-known research in which hospital patients who viewed plants from their windows recovered more quickly and used fewer pain reliving drugs than patients who viewed a building (Urlich, 1984; for more about the impact of a window view see Attention Restoration and Views of Nature). Lohr and Pearson-Mims (2000) purposed that indoor plants could have the similar pain relieving effect like window views of nature.

You can take plenty of these pain-relievers; photo by lsphotos

In Lohr and Pearson-Mims’ experiment participants were instructed to place their non dominant hand in an ice water bath and to remove it if it was too uncomfortable, with maximum immersion time limited to 5 minutes. (This is very common method for experimentally inducing pain.)

“Geet well soon”; photo by Little Pheasant

The same room was used for 3 experimental conditions (it was just decorated differently) – exposition to plants, exposition to decorative items (colorful posters, lamp), and no plants and no decoration (pictures here). Having the condition with decorative items is important because any distraction can help us tolerate pain, so with this experimental design authors were able to determine whether plants help us more than other distraction.

More beneficial than other distraction from pain?; photo by ellajphillips

Authors found that more subjects were willing to keep a hand submerged in ice water for 5 minutes if they were in a room with plants present than if they were in a room without plants. This was found to be true even when the room without plants had other colorful objects that might help the subject focus on something other than the discomfort, which shows that benefits of plants were not simply associated with their decorative value.

Their decorativeness is undeniable, but beneficial effects of indoor plants go beyond it; photo by yvestown

Park and Mattson (2008; 2009; according to Blingsmark, 2009) replicated Urlich’s findings on appendectomy and thyroidectomy patients who were randomly assigned to hospital rooms with or without plants during their postoperative recovery periods. Patients in hospital rooms with plants and ﬂowers had significantly fewer intakes of postoperative analgesics, more positive physiological responses (lower systolic blood pressure and heart rate), lower ratings of pain, anxiety, and fatigue, and more positive feelings and higher satisfaction about their rooms when compared with patients without plants in their rooms.

There are much more potential benefits of indoor plants; photo by alamodestuff

There are many potential psychological benefits of indoor plants, but I focused on pain relief because a recent review of experimental literature by Bringslimark et al. (2009) concluded that stress-reduction and increased pain tolerance were well supported by empirical findings. Other beneficial effects of plants, like faster reaction time, increased task productivity, mood lifting, increased job satisfaction, healthier physiological measures (blood pressure, heart rate, electrodermal activity, etc.) were more inconsistent and contingent on features of the context and on the people encountering them. In other words, plants might have the potential to do all that (and more) but there needs to be done some more research to determine who and when is more susceptible to their impact.

More research is needed to examine who and when is more susceptible to beneficial impacts of plants; photo by yvestown

To conclude, I really liked the words of Virginia Lohr, the author of the first study. She said that “plants humanize our surroundings” – instead of saying for instance that they plant-ize or naturize our surroundings. But I agree completely, because human approach to patients could for once have nothing to do with people, but be all about plants. An approach that’s inexpensive and easy to provide, too.

They humanize our surroundings, says Lohr; photo by Little Pheasant

References

Breen, S.C. (2009) Plants make us better, more civil people. Swarthmore College Bulletin (link)

Bringslimark, T., Hartig, T., Patil, G.G.The psychological benefits of indoor plants: A critical review of the experimental literature Original Research Article. Journal of Environmental Psychology, Volume 29, Issue 4, December 2009, 422-433.

Lohr, V.I. and Pearson-Mims, C.H. (2000). Physical discomfort may be reduced in the presence of interior plants. HortTechnology 10(1):53-58. (full text)