The Mind-Body Question
Throughout the history of psychology there has been a philosophical debate, known as the mind-body question, over whether the mind, or consciousness, is a separate entity (nonphysical) from the body or if the mind is a creation of the nervous system (Carlson). The two sides of this debate are Dualism, representing the dualism of the body and mind, and Monism, the idea that the mind is a part of the nervous system (Carlson). To test these theories, consciousness can be tested through the evaluations of altered perception such as blind sight, unilateral neglect, and the separation of the corpus callosum.
Blind sight is defined as the ability to accurately respond to stimuli, even though the person is blind (Carlson). An example of this would be being able to correctly reach for an object or state what direction lines are going. This is usually caused by damage to the mammalian portion of the visual system, while the reptilian or primitive portion is still intact. With the mammalian portion of the visual system impaired a person would be unable to perceive the visual stimuli but because the primitive portion is still functioning properly he or she can unconsciously react to the stimuli (Carlson). This means that even without conscious knowledge of a visual stimuli behavior can still be controlled. The damage to the mammalian brain but not the primitive brain shows that consciousness is not a property of all structures of the brain and that it can be impair by physical damage, supporting monism (Carlson).
Unilateral neglect is a syndrome caused by damage to the right hemisphere of the brain, producing the inability to notice what is to the person’s left side. Under certain circumstances though, a person suffering from unilateral neglect can respond to stimuli on the left half of his or her body or vision (Carlson). This leads physiological psychologist to believe that this means that they or not consciously aware of the left half of...