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Fascinating. Would something like this connection be cocaine specific?
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.
NAC has been shown to help with compulsive hair-pulling (trichotillomania)
Probably not. Quoting from the article:

N-acetylcysteine also increased the activity in the brain of a particular gene associated with plasticity – the ability of the brain to adapt and learn new skills.

Ibogaine, and it's effect on GDNF (a brain protein), is reported to have a similar effect[1] on both alcohol and heroin addictions.

[1] at least to a layperson like me.

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

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.
It sure took them a long time to get to this point. Here's the pivot line from the release:

The pathway links the basolateral amygdala indirectly with the dorsolateral striatum, circumventing the prefrontal cortex. This means that an addicted individual would not necessarily be aware of their desire to take the drug.

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.
Here is one recent review article with further references: http://www.sciencedirect.com/science/article/pii/S1074742714...

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/

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...

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/

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/

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/

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/

edit: NAC = N-acetylcysteine

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/

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