For example in the visual system, neurons processing different aspects of a visual scene compete with other neurons for activation, whoever gets activated determines what you see. The rules for who wins the activation contest determine who gets activated. The PFC sets and manages those rules. Go to the same place with a friend and each of you write down what you notice, can you guess what your underlying goals are?
The rules and goals form strong perceptual biases. They physically guide the flow of chemical and electrical activity along certain preferred electrical pathways in your brain. What you believe and the goals you have color the entire nature of all your sensory experience.
When it comes to perception, brains have a built in bias to confirm what they already know (or believe). Howard Hughes Medical Institute researcher Ranulfo Romo, explained:
"Perceptions instead arise in higher-order brain areas from a combination of sensation, attention, and expectation. The sensory representation is [just] to confirm something that you have already thought." http://www.sciencedaily.com/releases/2005/11/051106180409.htm
It would make sense that people who jump when they see a rope on the ground, because they thought it was a snake are more likely to stay alive than people who do the opposite. Our sensory systems also have an innate predisposition to believe rather than disbelieve.
Sites with info on the role of the PFC in cognitive control: http://www.psych.utoronto.ca/users/peterson/petersonlab/Library/Miller%20EK%20Prefrontal%20cortex%20Nature%20Neuro%202000.pdf
http://www.wellcome.ac.uk/doc_WTX035701.html http://help4teachers.com/prefrontalcortex.htm
For us brain owner this means, that changing our beliefs will change what we see and hear around us; our experienmce of reality.
The role of cognition and believing has great survival value. By changing our thinking, our frontal lobe has the ability to override what we see, what we pay attention to, how we interpret what we see and how we will attend to our environments in the future. We react quickly using cognitive shortcuts and live another day at which point, we can think about our thinking. The innate bias exists to believe what we see, but cognitive control and veto power has been demonstrated to belong to the brain owner.
Not only is there a built in perceptual bias to see what we believe, there is a built in neurochemical bias to think what we are frequently thinking. The more a set of neurons fires, the more frequently they are going to fire again. Again it makes sense that neurons firing more frequently for those thoughts that loom large in the brain owner's environment, are going to provide survival value.
Our brains assume that what is important is what we are thinking about.
The inverse of this for brain owners is that what we hear frequently, we believe and we pay attention to. Thus we make it more likely for those neurons to fire in the future, whether what we heard was true or useful, or not.
Other researchers highlight the importance of our brains' cognitive control in terms of attention and perception. Just as our eyes filter out infrared and our ears filter or certain hertz, our frontal lobes filter out reems of data that they deem irrelevant. This allows us to act quickly but does sacrifice accuracy.
In our brains, the longer a stimulus happens, the less important it is perceived to be. We will pay more attention when we first hear a loud sound. There is noticeably less neural firing over time. Repetition of sensory inputs can be seen to numb our neural firing while training can be seen to reverse this neural net inactivation. http://www.sciencedaily.com/releases/2005/08/050802061407.htm
If you'd like to see convince yourself that our brains are designed with perceptual distortions, go see what you believe, ( believe what you see??):
http://www.michaelbach.de/ot/index.html
http://www.pbs.org/wnet/brain/illusions/index.html
Optical_illusion common cognitive distortions arise from our perceptual distortions http://www.cfo.com/chart.cfm/5380281
Brain Science: It's Personal
Many of us have come to accept that 'seeing is believing', however
research is indicating that rather than believe what we see, in the majority
of cases, our brains are predictive in nature, and
We see and hear and feel what we expect.
Changing what we believe changes the stucture and functioning of our brains and immune systems, it also changes what we see, hear and feel..
