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The Brain as a Model Maker: Bias and Prejudice in Perception

cisrael's picture
We know that all brain operations involve pattern analysis and model making. The brain is biologically organized to process information through the construction of internal models. It searches and finds patterns in what it senses.  It extracts the features of patterns from the data and assembles those features into a model of the perceived object.

One problem with this feature-extraction system, is that it is prone to misconception and has a resistance to error-correction. A good example of this phenomenon can be demonstrated using visually ambiguous, cognitively unstable pictures. Show a person a picture of the famous old lady’s /young woman’s face, or the two faces and a goblet, and the subject sees one or the other of these patterns, but initially, not both. Or use the Neckor cube, whose perspective switches back and forth in the viewer’s eye without any actual change to the object. What is happening here is that the brain is seeking out a stable image, and resisting any information that contradicts that.  In these examples, such stabilization can be difficult. The brain works with the data available, and sticks to it, even though it may not reflect the complete information. The problem is that once the model is created, the brain may discard the original data and indiscriminately attribute ‘reality’ to the incorrect model.

A wonderful way to introduce students to the way their brains process information is through the use of these ambiguous cognitively unstable visual images. I propose to have the students do a series of experiments in class with some of these images.  The first goal is to simply to raise their curiosity about their own brains and the way it gets information; to get them to wonder about what is real and what isn’t. Secondly, I would like to see if they can arrive at the pattern generating paradigm of the brain, the brain as a constructor of information. We would then explore both the advantages and disadvantages of this system for human information processing and, by extension, human culture, leading to a conversation about bias, prejudice, and other types of intractable beliefs.

As a way of making this unit more engaging, I would like the students to measure certain of their own psycho-physiological reactions to perceiving ambiguity. We might wonder whether their heart rate/pulse, galvanic skin response, and neural activity vary when the image they are viewing switches from stable to unstable. The idea would be to give them some indicators of their bodies’ reaction to ambiguity, to help them understand why they may intrinsically avoid it.

I would like to purchase a basic science lab that would allow the students to take these measurements.  BioPack Systems makes a kit called SCILAB-I WITH STIMULUS RESPONSE PACK - SCILAB-I-SR which allows students to record and analyze their own heart rate, brain waves, muscle activity and eye movement. The cost is $550 and I would use the summer stipend toward the purchase.

Humans have a preference for bi-modal thinking. We prefer certainty; and feel discomfort with uncertainty. Our desire for certainty is so great that we often ignore or misinterpret contradictory data that might cause us to become less certain, in order to avoid the ambiguous state: a good lesson for a class of high school seniors!