
Cocaine addiction: Scientists discover ‘back door’ into the brain - Libertatea
http://www.cam.ac.uk/research/news/cocaine-addiction-scientists-discover-back-door-into-the-brain
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rurban
Uh, press releases. There is no back-door. What they found is the plain old
habituation effect, circumventing the cortex directly through the
hypothalamus, and in this case linking the basolateral amygdala (the pleasure
centre) with the dorsolateral striatum (the main centre for unaware behavior).
This is a normal effect, not everything can go through the consciousness (the
cortex), otherwise it will be overloaded. In fact 80% of all senses and
motoric effects are eventually bypassed this way.

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brenfrow
Can you give me a link on more information on this? I'm very interested in
including this type of research into one of my future presentations.

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joveian
Here is one recent review article with further references:
[http://www.sciencedirect.com/science/article/pii/S1074742714...](http://www.sciencedirect.com/science/article/pii/S1074742714000860)

That is "From ventral-medial to dorsal-lateral striatum: Neural correlates of
reward-guided decision-making" by Burton et al. They have a nice summary
picture.

The first paper that this press release talks about is about amygdala
contribution to this process (at least for cocaine addition), where the
basolateral amygdala (BLA) is involved as neural involvement in behavior
shifts from the ventral to anterior dorsolateral striatum (DLS) and then the
amygdala contribution changes to the central nucleus.

It looks like the BLA pathway to the anterior DLS they describe is through the
core of the nucleus accumbens to the substantia nigra. The central amygdala
projects directly to the substantia nigra.

I found this paper exploring the connection of the central nucleus and the DLS
("Amygdala central nucleus interacts with dorsolateral striatum to regulate
the acquisition of habits" by Lingawe and Balleine):
[https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3711777/](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3711777/)

Another interesting paper that talks more about the hippocampal system and DLS
is "Factors That Influence the Relative Use of Multiple Memory Systems" by
Packard and Goodman [pdf]:
[https://www.researchgate.net/profile/Jarid_Goodman/publicati...](https://www.researchgate.net/profile/Jarid_Goodman/publication/255715967_Factors_that_influence_the_relative_use_of_multiple_memory_systems/links/54d82aca0cf2970e4e76bf28.pdf)

For one view of the possible role of the amygdala, see Pessoa's 'Emotion and
Cognition and the Amygdala: From “what is it?” to “what’s to be done?”'
[https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2949460/](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2949460/)

Another interesting paper I found argues that the basic function of the DLS
could be "action chunking". "Investigating habits: strategies, technologies
and models" by Smith and Graybiel:
[https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3921576/](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3921576/)

ETA: I also noticed this paper the other day concerning value judgements in
the nucleus accumbens ("Dissecting components of reward: ‘liking’, ‘wanting’,
and learning." by Berridge et al.):
[https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2756052/](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2756052/)

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blazespin
Neat, but even looking at this
[http://www.nature.com/npp/journal/v37/n1/pdf/npp2011164a.pdf](http://www.nature.com/npp/journal/v37/n1/pdf/npp2011164a.pdf)
I see absolutely no numerical measurements of how much it "reduced craving".
No experiments against a placebo control or anything.

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enkephalin
_More than 20 clinical trials have employed NAC as an adjunctive treatment in
various psychiatric disorders. These include methamphetamine and cannabis
dependence, nicotine and cocaine addiction, pathological gambling,
obsessive–compulsive disorder, trichotillomania, nail biting and skin picking,
schizophrenia, bipolar disorder, autism, and AD. In most of these studies, NAC
had positive effects on clinical outcomes (Gere-Paszti and Jakus 2009; Samuni
et al. 2013)._

[http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3967529/](http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3967529/)

edit: NAC = N-acetylcysteine

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peteretep
Hrm, it's for sale on Amazon as an anti-antioxidant dietary supplement. Gwern?

~~~
ry_ry
Interesting, the article mentions it failing clinical human trials but not
why, presumably there was no significant health aspect if it's available as a
supplement.

Perhaps this will finally help me kick my 10-page-a-day HN habit?

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poelzi
right...

[http://www.ted.com/talks/johann_hari_everything_you_think_yo...](http://www.ted.com/talks/johann_hari_everything_you_think_you_know_about_addiction_is_wrong)

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aidos
Fascinating. Would something like this connection be cocaine specific?

~~~
danieltillett
I kind of doubt it. It would be very interesting to see if N-actly-cystine
would help control in other addictive behaviour. Of course there is the slight
issue that this is just in rats, but the fact that NAC is an over the counter
supplement makes it easy to test.

~~~
randomname2
NAC has been shown to help with compulsive hair-pulling (trichotillomania)

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amelius
There's also a substance called citicoline (CDP-choline), that has been used
as a partial treatment for addictive disorders, [1].

> Furthermore, citicoline appears to decrease craving and is associated with a
> reduction in cocaine use, at least at high doses in patients with both
> bipolar disorder and cocaine dependence.

[1]
[http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4139283/](http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4139283/)

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ommunist
Ha! I 'd like very much to see the results of clinical trials of
N-acetylcysteine to cure Internet (especially Facebook) addiction and game
addiction.

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elwell
Apparently /classic isn't a sufficient filter for HN anymore.

