Consciousness Flashcards
What is consciousness?
- the state or quality of awareness – awareness of thoughts, perceptions, memories, and feelings
- subjective experience
- if a being is capable of having a subjective experience, then there is something that it is like to be that being
What is the frontal lobotomy?
- treatment for psychosis, depression, anxiety, etc
- if something is wrong, cut it out
- popularity of this procedure waned in the mid 1950s following the discovery of partially effective antipsychotic medications
What is the split-brain operation?
- outdated surgical approach for treating seizure disorder
- cutting the corpus callosum
What is the corpus callosum?
- the bundle of nerve fibers that connect the left and right sides of the cerebral cortex
- enables the two hemispheres to share information so that each side knows what the other side is perceiving and doing
What are our cerebral hemispheres critical for?
- ability to consciously process sensory information
- our ability to consciously (purposefully) move our body in space
What is the crisscross of the nerve fivers in the cerebral cortex?
- The left brain is largely responsible for the right side of the body
- The right brain is largely responsible for the left side of the body
What happens when you cut the corpus callosum?
- the two cerebral hemispheres cannot directly talk to each other
- they can still send information downwards (to the brainstem and spinal cord) to control muscles
What did researchers find in split-brain patients?
- the patients’ improvements were short-lived and/or exaggerated
- cutting the corpus callosum did not do very much (good or bad)
- left hand sometimes actively worked against what the person was consciously trying to accomplish
- left hand controlled by processes outside their conscious awareness
- right hand, controlled by the left brain, never acted out of the ordinary
- after about a year, conflicts with left hand are rare
Split-brain patients and touch
- When a split-brain patient closes their eyes and touches a familiar but unidentified object with their left hand, they cannot identify the object out loud
Split-brain patients and vision
- When a split-brain patient sees an image only in their left peripheral vision, which is processed on the right side of the brain, they cannot verbalize what they see
What is the localization of language in the brain?
- language ability is located in the left cerebral hemisphere
- right brain can understand simple phrases and left hand can indicate answers to simple questions
Can split brain patients see an object in their right peripheral vision?
- with right hand, write yes
- say yes
- with left hand, point to no
Can split brain patients see an object in their left peripheral vision?
- with right hand, write no
- say no
- with left hand, point to yes
Can split brain patients tell if two objects are the same or different?
(are the objects the same?)
- with right hand, write don’t know
- say don’t know
- with left hand, point to don’t know
key - ring
- say ring
- pick up key with left hand