R1 Questions Flashcards
What is intra-cranial electrical stimulation (iES), and what did Wilder Penfield use it for between the 1930’s and 50’s?
Intra-cranial electrical stimulation (iES): type of direct brain stimulation that is used by neurosurgeons to elicit or promote various motor and cognitive effects.
Wilder Penfield continuously used iES to map cortical areas—on the outer layers of the cerebrum—that were able to process various sensory or motor functions.
Give an example of how neurosurgeons use iES in treating neural conditions such as Parkinson’s disease.
Neurosurgeons use iES for chronic electrical stimulation to permanently implant electrodes in certain areas of the brain. For neural conditions like Parkinson’s disease, deep brain stimulation produces consistent gentle electrical impulses to regulate tremors or abnormal impulses.
What are the eloquent and non-eloquent cortices? Name the example brain regions mentioned for both.
eloquent cortex: refers to the major brain areas that control daily function; if damaged, these areas would produce major neurological deficits. Areas include: primary motor cortices, auditory, visual, and somatosensory, as well as regions that control understanding and produce speech.
non-eloquent cortex: includes regions of the prefrontal cortex, which are able to be removed without causing significant damage to consciousness.
Which of these (eloquent versus non-eloquent) is more associated with conscious experience?
eloquent cortex; due to it containing the posterior regions, such as the parietal, temporal, and occipital lobes.
How does the Orion device work and what are its capabilities and limitations?
Orion: a small camera that is mounted onto glasses that converts different images into several pulses and wirelessly transfer them to fire sixty electrodes on top of the visual cortex.
This device is capable of allowing those to navigate throughout their surroundings, but does not allow people to recall shapes, letters, or varying figures.
Describe the brain-machine interface that enabled a monkey to play Pong without a controller.
The monkey was able to play Pong due to two small chips implanted into both of its motor cortices. With this wireless brain machine, each electrode was able to convey the monkey’s plan to move the paddle and the ball across the screen.
How many neurons are there in what Koch refers to as a “quinoa-sized bit of brain matter?” (Which BTW translates into approximately 1mm of cortex).
50,000 neurons
Speculate why the answer to #8 is an issue for understanding consciousness.
Based on that number, it shows how difficult for us to truly understand human consciousness, especially through technology and electrical stimulation. Over times, it has become easier to use scientific methods to explain the varying properties of the conscious mind; however, as more technological advances are brought into society to make and achieve, it is still unknown as to why the mind is truly conscious. Therefore, much more neurons will need to be required to discover more perception within the brain.
