Consciousness Flashcards
What is counsciousness?
The state/quality of awareness of thoughts, perceptions, memories and feelings
What is created by the state of awareness that derives from consciousness?
Subjective experience of what it is to be.
What were the effects of lobotomies?
Apathy, docility, weakness of emotions or opinions, child-like behavior
What is the corpus callosum?
Bundle of nerve fibers that connect the left and right side of the brain
What is the split-brain operation?
- Section of the corpus callosum
- Aims to treat seizures
What composes the outside brain?
Cell bodies
What composes the inside of the brain?
axons
What is epilepsy?
Condition in which a few neurons become extremely excitable and propagate the over-activity through axons.
What are the two main purposes of the cerebral hemispheres?
- Ability to CONSCIOUSLY process sensory information
- Ability to CONSCIOUSLY/PURPOSEFULLY move the body
What is the criss-crossing of the nervous system?
The right hemisphere is responsible for sensations and movements in the left hemisphere, and the opposite
How is vision lateralized?
The left field of vision of each eye is processed by the right hemisphere, and the right field of vision of each eye is processed in the left hemisphere.
What is the impact of damage to the cerebral hemispheres?
Not conscious of receiving sensory information
What is the main function of the corpus callosum?
Enables the hemispheres to share information in between themselves.
What parts of the brain coordinate bilateral body movements and integrate them after a dissection of the corpus callosum?
- brainstem
- spinal chord
What were the actual conclusions of the corpus callosum experiments?
- improvements were minimal or non durable
- no significant impact
How did the question of consciousness come to be related to the split-brain operation?
Some patients reported that their left hand was acting in a way that they could not control, as though it was being controlled by unconscious processes. It also sometimes went against what they were trying to do with the right hand.
What of touch in split-brain patients?
Touching an object with their left hand, they could not verbally identify it.
What of vision in split-brain patients?
Seeing an image in their left peripheral vision, they cannot verbalize what they see.
What happens when split-brain face stimuli that is directed exclusively toward the right brain?
Unable to verbalize it
How did split-brain patients adapt?
- One hemisphere takes over in a situation dependent manner
OR - Subcortical structures coordinate bimanual skills
Why were split-brain patiens unable to verbalize the stimuli treated by the right hemisphere?
The right brain does not possess speech
Where are language abilities located?
Mostly in the left hemisphere
What did Sperry discover about the right cerebral cortex (regarding language)?
- Ability to retain a small dictionary
- Can understand simple numbers/letters/short statement
THEREFORE the left hand can be used to indicate simple answers to simple questions
What did Sperry notice when split-brain patients performed an action that had been initiated by their right hemisphere?
they made up a post hoc answer, as if their left brain was trying to explain what the right brain had done to give it a sense
