When our brain is constructing our perception of our environment, it will introduce lines or connections where it thinks they should be, based on a set of assumptions about what it thinks it should be seeing. Our brains will compare different types of sensory input in order to construct one seamless picture. Irrespective of the data provided it will adjust one sense or the other in order to make things match, without one being aware that the original sensory data did not match. For example, when we look at someone clapping their hands, the two events of what we see and hear appear to be simultaneous to us, when in fact – because light travels much faster than sound – the two events of what we see and hear happen at different times. This is a constructed illusion in the brain, which is working in the background to synchronize the two events because it knows that they should both occur at the same time. As long as the visual and auditory information is within 80 milliseconds of each other, the brain will construct them as being simultaneous. One of our strengths as cognitive beings is making connections between different events, ideas, visual patterns, or other phenomena. Human cognition is so well designed to see patterns that we sometimes see patterns that are not even present. Brain processing is based largely on pattern recognition most likely because of its underlying structure as a neural network.
Attention is very significant to our construction of reality because we are constantly overloaded with a vast amount of sensory information, and it is not possible to pay attention to even a significant fraction of it at any given instance. As a result, we place a huge filter on most of the sensory information that reaches us and pay attention to only what our brains see as being important. We actually pay attention to a very small subset of the available information, which we manufacture into a complete account by adding pieces of information as needed. The end result is a story that is largely constructed by our brain, altered based on comparison with what others believe, and subject to manipulation in order to reduce cognitive dissonance; making it conform with our other beliefs and experience. Likewise, human memory is very much flawed in its workings. Like our perception, our memory is not a passive recorder; instead, our memories are constructed entirely by our brains. In fact, they are very much conditioned and contingent upon everything that we think and our overall conception of reality. In a study conducted by Ian Skurnik and colleagues in 2007, the researchers showed that as many as 27 percent of young adults incorrectly remembered a false statement as being true only three days after they were told of it, and this increased with age; 40 percent of older adults misremembered a false statement as being true. They remembered that they had heard the statement before, but they did not remember that it was false.3 We attend to a very small subset of information, which we weave into a complete story by adding constructed pieces as needed. The end result is a story that is largely a product of our cognitive workings where sensory input is constructed into meaningful patterns. Not only are the components of what we perceive constructed, but also how we put our perceptions together into a meaningful way is also constructed. Recognizing these innate fallibilities in human cognition is an essential step toward effective critical thinking.