magazine issue 4 2014 / Issue 20

Seeing mountains in molehills: Embodied visual perception of the environment

• written by Shana Cole & Emily Balcetis
• edited by Simone Schnall

You have likely experienced the phenomenon. Perhaps it occurred on the walk from the train after an exhausting day at the office. Or maybe you noticed it on the uphill trek to class while lugging a backpack stuffed with textbooks. That hill looming in front of you—surmountable most days and probably no more than a few degrees incline —right now looks more like Mount Everest. Likewise, the six-block walk from the train appears to stretch for miles. The way our surroundings look seems to change based on the state of our bodies. When we’re tired, out of shape, or loaded down, the environment can look quite daunting. And if our surroundings appear too challenging to move through, we may be less likely to do so. We might stop walking or call off our run if the distance looks too far or the hill looks too steep. In a dynamic and interactive way, our bodies influence they way we see the world around us, which can impact the way we move—or decide not to move—within it.

This phenomenon is not just anecdotal. Studies have found empirical support for the embodied nature of visual perception. Furthermore, research suggests that it is not only our physical states that alter the way we view the world, but our mental states as well. Understanding these mind and body interactions is important. Systematic misperceptions of the environment have implications for health and fitness. In this article, we’ll discuss research linking mind and body states to visual experiences, and we’ll emphasize the importance of developing interventions that shift perceptual experiences in ways that help people move more and work towards meeting their exercise goals.

Embodied visual perception (or ‘How Ryan Gosling sees the world’)

Visual perception is rooted in bodily states. In much the same way that our bodies can influence our thoughts, they can also affect our perceptions of how the world looks. An 18-year-old standing next to a 90-year-old at the bottom of a grassy hill may perceive the slope to be less steep than his wobbly neighbor. If Ryan Gosling stands next to Michael Moore looking down the length of Hollywood Boulevard, it’s likely the chiseled Gosling will perceive the distance to the Dolby Theater as closer than will the stouter Moore. Differences in body types and physical capabilities can produce differences in the way people see the environment.

Researchers have found empirical support for the notion that perception may depend on the physical resources we have available to us at any given moment. In one study, elderly and overweight people perceived the steepness of a hill to be greater than did younger, slimmer participants (Bhalla & Proffitt, 1999). In another study, people who suffered from chronic pain and were less capable of moving around perceived distances as further away than did healthier people (Witt, Linkenauger, Bakdash, Augustyn, Cook, & Proffitt, 2009).

Just as chronic, stable differences in fitness or physical prowess can affect the way people perceive their environment, so too can fleeting bodily states. In a recent study, researchers manipulated people’s energy states and tested the effects on perceptions of the slope of a hill (Schnall, Zadra, & Proffitt, 2010). The researchers first required participants to perform a boring and tiring task that sapped glucose levels and depleted their energy. The participants then consumed either a fruit drink sweetened with sugar, which provided glucose and boosted their energy, or a fruit drink sweetened with non-caloric sugar substitute, which provided no glucose or energy. Importantly, participants didn’t know which of the two they drank. Then researchers asked participants to stand in front of a large hill and estimate how steep the hill they saw before them looked. Those participants who drank the artificially-sweetened drink—those with low energy—perceived the hill as steeper than participants who drank the sugar-sweetened drink. The amount of physical energy people have influences their perceptual experiences of the world around them.

The mind matters:  Visual perception is motivated

Just as our bodies can impact our perceptual experiences of the world, so can our minds. Visual perception is not only embodied but is motivated as well. Recent studies from our lab suggest the strength of people’s motivations can influence how far away an object appears. In our studies, some participants saw items that were highly desirable and relevant to their goals and others saw items that were not. They then estimated how far away the objects appeared (Balcetis & Dunning, 2010). For example, in one of the studies, we placed a bottle of water a certain distance away from the participants. Some of the participants had just eaten salty pretzels, and others had just drank several glasses of water. We asked how far away the water bottle appeared. The thirsty participants who were presumably more motivated to drink the water perceived the water bottle as closer than did the quenched participants. People’s psychological states—their goals and motivations to attain an object—influenced how close the object appeared.