Alzheimer's disease

[clarsct]

So. As you may have noted, I've posted about this in other places, too.

I reserved this for the discussion of what we know, scientifically, which, as I recall, is damned little.

I guess the question is: How does it degrade brain function? Does it just affect memory, or does it affect your personality, too? Or is one just a by-product of another?

A vague question, maybe, but with any luck we can get a productive discussion out of it.

[clarsct]

Ok, the more philosophical side of memories can be found here:
http://206.225.95.123/forumlive/showthread.php?p=1285316#post1285316

If you are interested in such.

[clarsct]

A question has arisen in the R&P thread.

Is there a difference in brain function for experiences and memories? How does Alzhiemers effect these things?

[Xeriar]

The major processing of the brain appears to be done by neural network. Each neuron is connected to 1,000-100,000 other neurons, and when a neuron "fires", it sends an electrochemical signal down its axon to 1,000-100,000 other cells.

These cells are receiving firing inputs from a like number, and if the signal possesses a certain chemical strength, they will also fire, and so on and so on, about 300 times a second.

Regarding alzheimer patients, there appear to be one or two potential causes. One is the presence of tangles in the above network, though it is not clear exactly how this causes problems, it could certainly muddy intellectual capabilities.

The second is a combination of neural degeneration and a buildup of amyloid plaques, which (IIRC) prevent needed regrowth, basically, slowly killing the brain.

[Bowser]

Does it just affect memory, or does it affect your personality, too? Or is one just a by-product of another?The dementia definitely affects both the mental and physical state of the person and can introduce very serious personality changes of hostility and paranoia. Memory is just one aspect. To an extent it isn't even memory, it is also a matter of processing what the person remembers.

I watched the deterioration in my mother. Simple tasks, like peeling and cutting whole potatoes to make mashed potatoes, were reinvented. She no longer used the peeler she had used for decades. Instead, a fairly dull paring knife. But first she cut up the potatoes into small pieces and then attempted to peel them. That is an example of "sequencing" that can be found in other dementias, like Parkinson's.

Here is a list of symptoms: http://www.alzheimers.org/pubs/stages.htm

[Gurdur]

Is there a difference in brain function for experiences and memories?
Just taking this question:
Very much so. For example, Korsakoff's/Wernicke's syndrome means the inability to be able to form any new long-term memories, but sufferers are commonly in unaffected in other ways, i.e. they are not demented in the slightest.

Your question regarding "experiences" is very vague; there is a huge row of differential neurological conditions that affect various parts of perception but leave cognition completely unharmed.

[clarsct]

Thank you one and all for the responses.

The 'experiences' question came from a different thread, linked above. I was just wondering if there is a true (ie scientific/medical) difference between the two. Or if we're good enough to know that yet.

[Gurdur]

Thank you one and all for the responses.

The 'experiences' question came from a different thread, linked above. I was just wondering if there is a true (ie scientific/medical) difference between the two. Or if we're good enough to know that yet.
THe phenomenology of neurological experience and pathology thereof is well-advanced in study. The difference between experience and memory is real, but both affect each other.

[clarsct]

COOL!

Hmmmm.

Is there a 'layman's guide' around, or do I have to brush up my biochem to get a grip on this stuff? Any suggested reading, in other words?

[Kumar]

What about "Lipofuscin" deposits?

[Gurdur]

COOL!
Hmmmm.
Is there a 'layman's guide' around, or do I have to brush up my biochem to get a grip on this stuff? Any suggested reading, in other words?
Ouchie.
I can recommend you tons of reading, but your question is very imprecise as to what exactly it is you want to read up on. Neuroanatomy and neurophysiopsychology were part of what I did at uni and in clinical practice (diagnosis and rehab of aphasiacs and apraxics). For a very general, easy-to-read but still deep and useful introduction, see the books by
Harold Klawans (http://www.amazon.com/exec/obidos/search-handle-url/index=books&field-author-exact=Harold%2C%20M.D.%20Klawans&rank=-relevance%2C%2Bavailability%2C-daterank/002-5633560-0372061)
and
Oliver Sacks (http://www.amazon.com/exec/obidos/search-handle-url/index=books&field-author-exact=Oliver%20Sacks&rank=-relevance%2C%2Bavailability%2C-daterank/002-5633560-0372061)

Klawans is somewhat less ....wordy than Sacks, but both are good reading. Have fun!

[clarsct]

Thanks.

I am, actually, genuinely, interested in the subject. I know it seems a rarity on these fora at times.

[Gurdur]

Thanks.

I am, actually, genuinely, interested in the subject. I know it seems a rarity on these fora at times.
Feel free. It's my passion, neuro.