lecture notes

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13 Dec 2010
of 9
PSY lecture Jan 18
Short answers come from the slides.
Basics of communication in nervous system.
Billions of neurons are getting engaged every single time we do
Split brain, endocrine
Biological bases of behavior
Communication in the nervous system
Organization of the nervous system
Researching the brain
Components of the neuron.
-Binary code. It either senses repulses or it doesnt. All
dependent on the firing of the neurons. If it doesnt fire, it is
the basics of the medical diseases.
-Dendrites: Receiver of the information. Places that receive
information. They are like locks. They’re sitting there and
wait for the key to go in. If the key turns into the lock, other
keys say shut it off. Those are inhibitory. Dendrites are
receiving information from the terminal buttons from other
neurons. Terminal buttons lay just above dendrites. The
space between dendrites are synapses.
-Cell body: transmitter of molecules. Permeable. Ions can
flow back and forth.
-Axon: where summation of energy comes in. Tells neuron
to fire. Electro chemical energy fires down. As the energy
fires down the terminal buttons, it forces them all to go to
the synapse.
-Dendrites cell body axon terminal buttons.
-The faster the Myelin insulates, the faster the information
proceeds. It reacts a lot faster when you touch something
hot. Pain fibers are really fast and tells us to take our hands
away from something hot. We create myelin by
experience. Myelin gets used to routine. Myelin is made of
glia (its like glue)
Graded potentials
-different types of neuro connections. 3 different types
-afferent: body to brain (CNS)
-efferent: CNS to body
-receiving information and transmitting information. It takes
billions of connections to make even a small movement.
-Stimulation of ions : Open up membrane. More sodium
ions on the outside. On the outside, potassium ions. (dont
worry too much about knowing this). Difference of
charges. Open up sodium channels or close them down.
Once enough signals are received to tell the cell body to
open up, the cell body opens up so that the sodium ions
flow in. It creates more energy by doing that. It reaches
the threshold. If it reaches the threshold (it it receives
enough), it fires. Neuron can only fire once, and it has to
rest. This is when it reaches refractory period. After this
period, it goes back to normal.
-Hyperpolarization: inhibitory message says shut it down.
The Action potential
-Entire process that leads to the firing of the neural impulse.
Neurotransmitters send information by either locking into
dendrites or not. Each transmitter is like a key. It can be
excitatory or inhibitory. Are generated at the dendrites
where we receive information. Open up or dont open up
the channels. They either send inhibitory or excitatory. If
one neuron receives 20 excitatory and 10 inhibitoy, it will
move accordingly to the excitatory until they receive
enough. If theres more excitatory, we polarize, if theres
more inhibitory, we depolarize.
-Action potential axons move toward the terminals. Go or
dont go.
Details of the synapse
-Multiple synapses for each neuron. Each of the synapse
will react in different places. We can stimulate just by
having thoughts or by the environment. Fires the action
potential down, hits the terminal button.
-Receptor sites change. Were self-regulatory. If youre
taking too much cocaine, it will process so that the brain
doesnt receive too much dopamine. If you stop smoking
cocaine, there wont be enough dopamine and thats
when you start craving. Were always changing.
-Any behavior is connecting to a different neuron.
-If they bind: they will be taken and go to either excitatory
or inhibitory.
-If they dont bind: terminals suck in the unused transmitters
so that were not wasting them.
-Some wont bind and wont be re-uptaken. will be
deactivated and removed.
-Serotonin is very important. Sexual dysfunction, gaining
weight. We have side effects because we have limited
numbers of neurotransmitters. All neurotransmitters are
created every day. What you eat, how you think, your
emotional activity, drugs that you take, where you live, if
you exercise or not, etc. will affect the neurotransmitters.
Exercising in the morning will create more serotonic
neurotransmitters. If youre not having enough nutrition,
thats when neurotransmitters get messed up. The way
that we think determines what neurotransmitters we