Midterm 1 Flashcards
What is consciousness?
It is the state or quality of awareness. Awareness of thoughts, perception, feeling.
Explain why consciousness creates a subjective experience
State of awareness creates a subjective experience since it is based on or influenced by personal feelings, tastes, or opinions. If a being is capable of having subjective experiences, then there is something that it is like to be that being.
Explain about lobotomy in the 1940s
A lobotomy disrupts the connections between the frontal cortex and the rest of the brain, particularly the thalamus by using a tool to go through the eye socket . This surgery consisted of making holes in the skull, removing some brain tissue, and severing the connections between the frontal lobe and the thalamus.
It was advertised as a treatment for psychosis, depression, anxiety.
It was very successful and made caring for individuals who were “harder to deal with”, easier.
Mental health strugglers typically did not register for these surgeries rather their loved ones.
Explain split brain surgery
An outdated surgical approach for treating seizure disorder (epilepsy) that involves cutting the corpus callosum. This surgery was meant to help slow down activity to help stop seizures and epilepsy.
What is the corpus callousum?
The corpus callosum is a bundle of fibers that interconnects the two cerebral hemispheres. It enables the two hemispheres to share information so that each side knows what the other side is perceiving and doing.
Why are cerebral hemispheres important for conscious perception?
Cerebral hemispheres are important for conscious perception and purposeful movements. It is important to help process sensory information. You can sometimes unconsciously process sensory information. Once sensory information reaches cerebral cortex, they are conscious.
Explain the different sides of the brain and what they are responsible for?
Each cerebral hemisphere is responsible for one half of the body, but the nerve fibres mostly crisscross.
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. For example, damage to the left cerebral hemisphere will selectively disrupt movements and sensory processing on the right half of the body.
Explain vision and how it is processed in the brain?
When you look at something (a fixation point), everything you see to the left of that spot is processed by the right brain, and everything you see to the right of that spot is processed by the left brain.
Explain how the communication between the right and left cerebral cortex’s communication is compromised during split brain surgery.
If the corpus callosum is cut, the two cerebral hemispheres cannot directly talk to each other. However, they can still send information downwards
(to the brainstem and spinal cord) to control muscles.Both brains will still send down signals for muscles movement, even if both sides of the brain cannot communicate with each other due to the corpus callosum being cut off.
How was the split brain surgery examined?
26 patients received split-brain surgery around 1940.
The doctor claimed the surgery was a success (i.e., reduced frequency and intensity of seizures with minimal side effects).
An independent group of scientists soon re-examined these patients with a host of neurological and psychological tests and concluded that
1.the patients’ improvements were short-lived and/or exaggerated
2. cutting the corpus callosum did not do much (good or bad)
Explain Roger Sperry
Roger Sperry at Caltech (California) became confident the corpus callosum was important for something. His lab cut the corpus callosum of cats and monkeys, where they could be confident the surgeries were clean and complete. When the split brain surgery was done again in 1962, the neurosurgeon invited Sperry to conduct pre and post operative examinations
Explain some of the side effects of the split brain surgery.
Some of these patients later said that their left hand sometimes seemed to have a mind of its own and actively worked against what the person was consciously trying to accomplish. The right hand, controlled by the left brain, never acted out of the ordinary. Its actions were always consistent with the person’s conscious intentions.
Explain some surgeries done on split brain surgery patients.
Touch test: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.
Vision test: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. Split brain patients cannot say out loud something that only the right brain sees.
What did the exams conducted on patients of split brain surgery conclude?
Split brain patients appear to be unconscious of – cannot verbalize – any stimuli directed exclusively to their right brain.
Explain where language is found in the brain and how this affected individuals with brain damage.
Language ability was found in the left side of the brain. People who damage the left side of the brain cannot process language or writing. The left brain also controlled the mouth and ability to speak.
Right side of the brain damage does not damage the ability to read or write. Therefore, when the left brain is damaged and cannot verbalize, they can use the right side of the brain to answer simple questions as they could understand simple numbers, letters, and short statements.He also found split-brain patients could use their left hand (controlled by their mute right brain) to indicate answers to simple questions.
