Computer Science 129 Science, Computing and Society Week 8 Chapter 6
GRE/GMAT WORDS • Veracity – truthful • Prodigal – wasteful, extravagant • Alacrity – an eager willingness to do something • Prosaic – dull and lacking imagination
Interesting Stories • Alien hand syndrome is a rare neurological disorder in which one hand functions involuntarily, with the victim completely unaware of its action. Symptoms include involuntary reaching and grasping, touching the face or tearing at clothing. More extreme cases have involved involuntarily stuffing food in the mouth, preventing the normal hand from completing simple tasks and self inflicted punching or choking.
Interesting Stories • Think of the corpus callosum as the brain's e-mail server, a bundle of message sending nerves that connect and share information with the two hemispheres. Alien hand syndrome is a result of damage to these nerves. This damage most often occurs in brain aneurysms, stroke patients and those with infections of the brain, but can also manifest as a side effect of brain surgery, most commonly after a radical procedure that treats extreme cases of epilepsy.
Chapter 6 The brain performs an incredible number of tasks: • It controls body temperature, blood pressure, heart rate and breathing. • It accepts a flood of information about the world around you from your various senses (eyes, ears, nose, etc.). • It handles physical motion when walking, talking, standing or sitting. • It lets you think, dream, reason and experience emotions.
Chapter 6 The Brain and Vision: Class Experiment: Wave opened fingered hand in front of eyes (notice blur) Now hold open fingered hand in front of eyes and shake your head (no blur)
Chapter 6 Why? Vestibulo-Ocular Reflex (VOR) The vestibulo-ocular reflex, or VOR, is a reflexeye movement that stabilizes images on the retina during head movement by producing an eye movement in the direction opposite to head movement
Chapter 6 When the head moves, the VOR responds with an eye movement that is equal in magnitude but opposite in direction.
Chapter 6 Brain receives input, processes the input, and gives an output It does this at a cellular level and at the level of an organ
Chapter 6 Some Scientists do not believe the brain “computes” Consider the “Chinese room” analogy Man in room who does not speak or read Chinese The room is sealed off except for one door
Chapter 6 Man in room is given cards with Chinese symbols on them and a book of instructions (written in English or his native language) The instructions tell the person what symbols to send out in response to Chinese messages slipped under the door
Chapter 6 The Man uses the instructions as a computer uses a computer program The man does not know what or if he is communicating, but to an outsider his responses could look reasonable
Chapter 6 Conclusion is that a computer computes whereas a brain thinks, understands and has consciousness Brain is biological, not a machine
Chapter 6 Argument seems to be semantical Definition of “computing” is the debate I believe our brains compute, it is just our instruction booklet changes minute to minute depending upon what has happened to us.
Chapter 6 The complete function of the brain is still unknown 4 Regions of Brain: Cerebrum (4 lobes) Cerebellum Diencephalon Brain Stem
Chapter 6 The medulla oblongata, located in the brain stem, manages the reflex centers for: • Vomiting • Coughing • Sneezing • Swallowing • Hiccupping • Respiratory rate • Vasoconstriction
Chapter 6 These are perfect examples of input, process, output analogy
Chapter 6 The Neuron is the basic unit of our central nervous system which includes our brain
Chapter 6 • Something activates a dendrite and it passes an electrical signal down the soma (cell body) and the axon to the tip of the synapses. The presence of this electrical signal causes a change in permeability to the tip of the synapses allowing neurotransmitters to seep out into the synaptic cleft. The neurotransmitters bind to receptor sites on the tip of the post synaptic neurons dendrites. This binding causes an electrical signal to go down the post synaptic neuron and the process repeats. This sends a signal very quickly.
Chapter 6 Neurons use chemical mechanisms to transfer an electric impulse, or action potential, from cell to cell to affect a response http://www.bristol.ac.uk/synaptic/basics/basics-1.html Go to this website and read this one page
What You Should Know • Know all GRE/GMAT words
What You Should Know Define: Vestibulo-Ocular Reflex (VOR)
What You Should Know What are the four primary regions of the brain?
What You Should Know SHORT ESSAY: WHAT SEVEN REFLEX CENTERS DOES THE MEDULLA OBLONGATA CONTROL AND HOW DO THEY RESEMBLE A COMPUTER PROCESS
What You Should Know SHORT ESSAY: EXPLAIN CHINESE ROOM ARGUMENT AND WHAT IT HAS BEEN PURPORTED TO ILLUSTRATE
What You Should Know SHORT ESSAY: HOW DOES A NEURON USE CHEMICAL MECHANISMS TO TRANSFER AN ELECTIRCAL INPULSE