The Percept/Image Conflict

“So drawing is a way of seeing. A vision of how we interact with the world.” - Survey #10

Recent experiments using brain scanning technologies have revealed that the way our brains produce mental images activates the same mechanisms, and subsequently the same parts, of the brain as actually seeing real objects in the outside world (which will be referred to as “percepts”).

A leading figure in the field of cognitive psychology and mental imagery, Stephen Kosslyn has made advances in determining the exact areas of the brain that are involved in the vision and visualizing processes. In an article on the cognitive processes required for drawing, Chris Frith (from the Institute of Neurology in London) and John Law (of Bath College of Higher Education) allude to this research: “[Kosslyn] used functional brain imaging to confirm that visual imagery activates the same areas of the visual cortex as those that are activated when stimuli are actually present” |Frith, 1995|. Kosslyn proposes that this duality in function of visual processes is part of a brain economy strategy — that instead of having separate areas of the brain responsible for incoming and outgoing visual information, the brain simply reverses the direction of the flow of that information. While this leaves more room in the brain for controlling other bodily and sensorial functions, it does have a negative effect on our visual system: our visual imaginings must compete with the steady stream of incoming visual stimuli from the physical, visual world around us. Imagine, if you will, that the incoming visual percepts passing through our visual system are traveling along a one-way highway from our eyes to our brain; traffic on this highway is thick and moving at break-neck speed. Now imagine that our mental images are trying to traverse this highway in the wrong direction, dodging the oncoming traffic, trying to avoid a collision which might cause it to become lost in the throng of incoming visual stimuli.

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fig. 14. the percept/image conflict

There is an inherent upside to the percept/image conflict, however: it is possible for real images to become the “underlay” to our imagined ideas. This superimposition of ideas onto reality often happens without conscious awareness and typically leads to the remembrance of a memory that is similar to the visual percept, and can be as simple as seeing a balloon and thinking of how it resembles a lollipop. We intentionally make use of layering our mental images onto percepts as well. If you were to wonder about repainting the exterior of your home, you could sit inside and imagine the shape and form of the house and the application of the new color, but this requires you to construct the mental image of the house, the roofline, the shutters, the yard, the trees around back, the cracks in the driveway — wait, where were we? You could instead walk outside and look at your house, this percept becoming the framework (or “underlay”) for imagining the new exterior color.

Our visual imaginings must compete with the steady stream of incoming visual stimuli from the world around us.

When we are trying to recall the way something looks, many people close their eyes to shut out the visual distractions assaulting their eyes. This is one way of “quieting the noise” — stopping traffic on that one-way, high-speed visual highway — momentarily to allow our brain an opportunity to produce its own, internal images. One way of resolving this percept/image conflict is to transform our mental images into external visual stimuli, and one way of doing this (perhaps the most expedient) is to draw them. Turning our ideas into drawings allows our visual system to assimilate our images into the steady stream of percepts, therefore allowing other visual processes such as spatial relationship detection and pattern recognition to take place subconsciously.