EDIT. Oh, for goodness sake, do I have too much time on my hands for this stuff? Again, sorry for a lengthy post, but I do hope my intentions are considered to be helpful, more than literary verbal assault on brain's etc.
Disclaimer. I may read like I know what I am talking about, but I can assure you I am not an expert in any way, but, I value discussion greatly.
Onwards!!!!
I found this after reading Planetdave's post #6 of this thread.
www.genomenewsnetwork.org/articles/09_00/DRD4_gene.shtml ---------------
Planetdave, I could not comprehend the article fully, but, I used some of my quickly fading logic functions.
So, before it fades away, I will take a wild, blind stab in the dark about the theory.
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What I believe to be scientifically correct--- Dopamine is currently considered to be the neurotransmitter of reward, usually released after, er, satisfying events in one's life, whether they be BAD or GOOD to others'. As long as the person, gets a dopamine boost, they feel good, unless they get so much, usually from drugs OR the reverse dopamine Genetic trait (in which case they are permanently high, BUT NO PSYCHOSIS? HMMMMMM....) Even shoplifting gives a buzz or is that kleptomania or both or one..? aRgh!
Dopamine apparently is also, as most of us know a big player in what is "currently" known as AD/HD (any type).
As D4 dopamine gets to near-optimum (that is probably the best anyone can hope for) levels, a more satisfying focus ability is gained.
Of course, I suppose it is purely the dopamine released which causes the reward feeling and not a good feeling causing dopamine release, if you know what I mean.
I won't say any more because,
I suspect some on here have done more research than me, so feel free to blast me.NOTE, IF you don't already know - After a quick read around "the internets", it seems that psychosis, is certainly not just down to D2 or D4 receptors.
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FACT FROM THE DOCUMENT......The research found, in multiple countries, that some people have 1 repeat of the DRD4 receptor gene, giving theoretically double the receptors. (as Planetdave stated, it's also known as a 120/240 polymorphism. If I understand correctly, the DRD4 gene is normally 120 base pairs of DNA, versus 240 BP for those who have 2 genes of DRD4.
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en.wikipedia.org/wiki/DRD4I believe that the D4 is the executive functioning area(front lobe) dopamine receptor?
My thoughts: This therefore gives them a 2x difference over people with 1 gene of DRD4 Now, if this is a 2x amount of receptors, then, does it mean that the beneficial dopamine processing flow vs 1x is doubled exactly? If it is, then, ADHD symptoms would be theoretically, almost non-existent (or far less existent). I won't say completely removed because genetics and the brain are just too complicated, in my un-professional opinion.
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Link 1 shows a possible cause or effect based on more or less dopamine receptors in the brain of rats, with regards to obesity and a blunted dopamine reward system.
www.bnl.gov/bnlweb/pubaf/pr/PR_display.asp?prID=07-97-----------------------------------------
Link 2 One important aspect of drug addiction is how cells adapt to previous drug exposure.
www.utexas.edu/research/asrec/dopamine.htmlQUOTE For example,
long-term treatment with dopamine antagonists increases the number of dopamine receptors. This happens as the nervous system tries to make up for less stimulation of the receptors by dopamine itself. Likewise, the receptors themselves become more sensitive to dopamine. Both are examples of the same process, called sensitization.
A type of sensitization.
An opposite effect occurs after dopamine or dopamine agonists repeatedly stimulate dopamine receptors.
Hereoverstimulation decreases the number of receptors, and the remaining receptors become less sensitive to dopamine. This process is called desensitization. END QUOTE
So, the brain always tries to optimise by using what it has......
So, someone who has less dopamine receptors (no repeated DRD4 gene) would Theoretically struggle to get the rewards and possibly use stimulation seeking behaviour (gambling, risky behaviour, mad financial decisions, smoking, drinking, fighting, eating, you name it!)
If this is the case, maybe they would need more of a nutrient that the majority of people have to enable them to have faster dopamine building abilities which would make up for the half (1x) level of receptors?
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Link 3
?F?
"?!? I tried to understand this, but it's painful for me....Just too much, I think I have worn my brain out now...
www.pnas.org/content/97/14/7673.full.pdf -------------------------------------
Link 4- Does not like DRD4 polymorphism's at all with regard to "novelty seeking" (polite phrase for some AD/HD symptoms?)........
www.nature.com/mp/journal/v7/n7/full/4001082a.html---------------------------------
zzzzzzzzzzzzzzzzzzzzzz, I can't take anymore...
I just spent
1 hour FAR TOO LONG or more on this groan!
I started at 1130am, got distracted, did a few things, had some food, took some camera shots, messed with irfanview compressing them, blah , now its 442pm and finally ,I can post........
Why do I bother when I should just leave it to the people who trained to do research/sciene jobs..
I suppose some would say that's the nature of AD/HD Born to explore?
If you got this far, congratulations.