Computer Science 129
Science, Computing and Society
Week 8
Chapter 6
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GRE/GMAT WORDS
• Veracity – truthful
• Prodigal – wasteful, extravagant
• Alacrity – an eager willingness to do
something
• Prosaic – dull and lacking imagination
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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.
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Interesting Stories
• Think of the corpus callosum as the brain's email 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.
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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.
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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)
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Chapter 6
Why?
Vestibulo-Ocular Reflex (VOR)
The vestibulo-ocular reflex, or VOR, is a
reflex eye movement that stabilizes
images on the retina during head
movement by producing an eye
movement in the direction opposite to
head movement
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Chapter 6
When the head moves, the VOR
responds with an eye movement that is
equal in magnitude but opposite in
direction.
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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
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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
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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
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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
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Chapter 6
Conclusion is that a computer computes
whereas a brain thinks, understands
and has consciousness
Brain is biological, not a machine
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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.
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Chapter 6
The complete
function of the
brain is still
unknown
4 Regions of Brain:
Cerebrum (4 lobes)
Cerebellum
Diencephalon
Brain Stem
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Chapter 6
The medulla oblongata, located in the brain
stem, manages the reflex centers for:
1. Vomiting
2. Coughing
3. Sneezing
4. Swallowing
5. Hiccupping
6. Respiratory rate
7. Vasoconstriction
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Chapter 6
These are perfect examples of input,
process, output analogy
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Chapter 6
The Neuron
is the basic
unit of our
central
nervous
system
which
includes our
brain
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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.
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Chapter 6
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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/basics1.html
Go to this website and read this one page
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What You Should Know
• Know all GRE/GMAT words
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What You Should Know
Define:
Vestibulo-Ocular Reflex (VOR)
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What You Should Know
What are the four primary regions of the
brain?
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What You Should Know
SHORT ESSAY:
WHAT SEVEN REFLEX CENTERS DOES
THE MEDULLA OBLONGATA
CONTROL AND HOW DO THEY
RESEMBLE A COMPUTER PROCESS
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What You Should Know
SHORT ESSAY:
EXPLAIN CHINESE ROOM ARGUMENT
AND WHAT IT HAS BEEN PURPORTED
TO ILLUSTRATE
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What You Should Know
SHORT ESSAY:
HOW DOES A NEURON USE CHEMICAL
MECHANISMS TO TRANSFER AN
ELECTIRCAL INPULSE
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