subconscious level.
As we’ve seen in Part One, nature appears to have some
immediate effects: a lower pulse rate and the beginnings of a
parasympathetic nervous system response leading to feelings of peace
and well-being. Korpela scoured the literature and came up with a sort
of time-response matrix. Thanks to his faces study, he knew the
quickest responses: “Within 200 milliseconds, people react positively
when they see images of nature,” he explained. “The picture you’ve
seen affects how you respond, because the picture evokes your
emotions.” Moving up the matrix, Ulrich’s experiments with the
bloody woodshop videos followed by nature videos showed a decrease
in subjects’ heart rates, in facial muscle tension, and changes in skin
conductance typically occurring within 4 to 7 minutes. The Japanese
and Finnish studies found lower blood pressure, lower circulating
cortisol and improved mood after 15 to 20 minutes. At around 45 or
50 minutes of being in nature, many subjects show stronger cognitive
performance as well as feelings of vitality and psychological
reflection. What if Korpela could thread all these observations
together in a way that enhanced the effects in a real-world
application?
He came up with the idea of a “Power Trail,” a well-signed, self-
guided nature walk that maximizes nature’s beneficial effects. Hikers
wouldn’t need a specially certified ranger or a class or a big healing
forest, just some views, ideally including water, and strategic
instructions. In 2010, the Ikaalinen Spa in central Finland let Korpela
construct a trail network around its property with government funding
(and about the word “spa”: lest you think it connotes an exclusive
enclave for ladies in lululemon, you should know that, in Finland, spa
visits are a federal benefit for workers in need. Yet another reason to
brave the sea ice and move to Finland).
The trail was an immediate success, according to Korpela and
Tyrväinen, and now there are half a dozen similar ones throughout