What is meant by the two-way street in Lauria's model. Give one
example
100 words.
Also  if neuron axons were conducted backwards and forwards what
problems could occur =would it improve information processing or help
relieve depression

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Request for Question Clarification by weisstho-ga on 06 Jul 2002 20:41 PDT

Just curious . . . is this homework or take-home final?

The best resources to start with for these questions are your own
notes, handouts, and textbooks from class.  You are more likely to get
the answer that your instructor expects.

Luria's Functional Units
http://vcs2.ccc.cccd.edu/crs111/luria.htm

Luria's Model (1973) of Brain Function
http://www.biofeedback.co.za/neuropsy-overview.htm

The Luria model of information processing
http://cleo.murdoch.edu.au/gen/aset/ajet/ajet1/win85p59.html

Learning and Behavior
"The Brain/Learning relationship is a two-way street...we now know
that:­ changes in behavior modify neuronal structure­ changes in
neuronal structure alter behavior"  I don't think this is in reference
to Luria's model so I wouldn't use this as an answer unless you knew
it was correct.
http://216.239.33.100/search?q=cache:GEdTQfp3vOwC:www.usc.edu/dept/LAS/ir/classweb/318/NIR31809BrainAndLearning.PDF+axon+%22two-way%22&hl=en&ie=UTF-8

The second question is unusual (did you copy it correctly?).  I think
it wants you to think about how the nervous system operates and come
up with your best guess for this hypothetical situation.  Use an
analogy of changing a one-way one-lane bridge (since two-way street
was mentioned earlier) to two-way.  What problems would occur?  What
has to happen to allow two-way traffic?  What happens to the rest of
the neuron and the nervous system if it flows both ways?  What are the
current theories about the cause of depression and would a
bidirectional axon affect the cause?
://www.google.com/search?hl=en&lr=&ie=ISO-8859-1&q=neuron+axon
http://vv.carleton.ca/~neil/neural/neuron-a.html
http://faculty.washington.edu/chudler/cells.html
http://psych.athabascau.ca/html/Psych289/Biotutorials/1/intro.shtml
http://home.earthlink.net/~drbobshields/Depr.neuro.html

Good luck.

I am unfamiliar with Luria's model, so I am unable to help you out
there. With respect to the second question, however, you cannot think
of it as changing a one-way street into a two-way street, as suggested
by ulu. For example, if you stimulate the middle of an axon with an
electrode, you can automatically generate an action potential in each
direction. It's not the same as street traffic.

What is perhaps more important, however, is what happens when the
action potential reaches the axon terminal. If it triggers enzymatic
cascades that result in the release of neurotransmitters from synaptic
boutons, then this may have an influence on conditions such as
depression. Whether this helps to relieve depression depends on the
type of neurotransmitter. If it is serotonin, for example, its release
may relieve depression -- or at least that's the rationale behind
keeping serotonin available in synapses (hence the proliferation of
selective serotonin reuptake inhibitors or SSRIs). But if
acetylcholine is released, it may do nothing for depression (or maybe
it does, I don't know for sure).

As for improving information processing, that makes no sense. Having
action potentials travelling both ways down a neuron won't "double"
your processing power or anything silly like that. You may get more
signals travelling around in your brain, but they won't necessarily do
anything significant.

For more information on biopsychology, I suggest reading a good
textbook. My favorite is aptly titled "Biopsychology" (4th ed.) by
John Pinel. You can easily find it for purchase on-line.

In posting my comment, I modified it based on the "clarification"
asked for by weisstho.  Hence, I did not want to state a direct answer
(leave that for the "official researchers"), especially for a question
that needed some sort of clarification, perhaps from the instructor. 
The additional questions I posted, which cogpsych answered, were to
help herity break down the problem.

I'm not a neuro-anything, but I comprehend the basics as taught.  I
think the analogy of the axon as a one-way one-lane road still works. 
Yes, the signal can travel both ways as cogpsych stated, but what
happens if you send an action potential "car" in from both ends?  A
collision occurs due to the refractory period of both action
potentials.  In general the whole neuron is built to have information
flow one-way.  http://gened.emc.maricopa.edu/bio/bio181/BIOBK/BioBookNERV.html

Coming from a computer perspective, making axons conduct both ways
requires a major change to all the hardware; and the software needs to
be redesigned.  It's performance and bugs will have to wait until we
get the new system up.  Very difficult to predict the emergent
behavior of such a complex system.
http://www.amazon.com/exec/obidos/ASIN/1579550088