28 July 2008 2 Comments
Following my two earlier posts about mirrors (here and here), I read with much interest this article from the New York Times discussing the scientific basis of perception distortions generated by mirrors. Here are some extracts:
To scientists, the simultaneous simplicity and complexity of mirrors make them powerful tools for exploring questions about perception and cognition in humans and other neuronally gifted species, and how the brain interprets and acts upon the great tides of sensory information from the external world. They are using mirrors to study how the brain decides what is self and what is other, how it judges distances and trajectories of objects, and how it reconstructs the richly three-dimensional quality of the outside world from what is essentially a two-dimensional snapshot taken by the retina’s flat sheet of receptor cells. They are applying mirrors in medicine, to create reflected images of patients’ limbs or other body parts and thus trick the brain into healing itself. Mirror therapy has been successful in treating disorders like phantom limb syndrome, chronic pain and post-stroke paralysis.
In other words, it seems perfectly possible to trick the brain into seeing and reacting to a perceived reality, even though one’s mind is completely conscious of the process! Fascinating. It does make one think about the relationship between the conscious mind and the involuntary processes controlled by the brain which seem out of the control of the mind.
In addition, the science also seems to indicate that distortion is embedded a priori in the mirror perception itself, i.e. what we see is necessarily a distortion of how we really are.
Outline your face on a mirror, and you will find it to be exactly half the size of your real face. Step back as much as you please, and the size of that outlined oval will not change: it will remain half the size of your face (or half the size of whatever part of your body you are looking at), even as the background scene reflected in the mirror steadily changes. Importantly, this half-size rule does not apply to the image of someone else moving about the room. If you sit still by the mirror, and a friend approaches or moves away, the size of the person’s image in the mirror will grow or shrink as our innate sense says it should.
Philosophically speaking, there may be no way of seeing ourselves ‘as we really are’. Though I suppose that should not be reason to stop trying.
Image: Rear view mirror. Source: stock.xchng