28 January 2007

Smoking is all in the mind (or rather the brain)

Yesterday’s New York Times carried a fascinating article about research that may link cigarette addiction to a specific part of the brain. Scientists studying stroke patients found that damage to a part of the brain known as the Insula can instantly break a smoking habit. People with the injury who stopped smoking found that their bodies effectively forgot the urge to smoke.

The finding, which appears in the journal Science, may well have a major impact on both research into addiction and treatment. Future therapies might focus on the insula, a prune-size region under the frontal lobes that is thought to be associated with visceral states - gut feelings.

The researchers, from the University of Iowa and the University of Southern California, examined 32 former smokers, all of whom had suffered a brain injury. The men and women were lucid enough to answer a battery of questions about their habits, and to rate how hard it was to quit and the strength of their subsequent urges to smoke. All had smoked at least five cigarettes a day for two years or more, and 16 of them said they had quit with ease, losing their cravings entirely.

The researchers performed M.R.I. scans on all of the patients’ brains and found that the 16 who had quit easily were far more likely to have an injury to their insula than any other area. The researchers found no association between a diminished urge to smoke and injuries to other regions of the brain, including tissue surrounding the insula.

“There’s a whole neural circuit critical to maintaining addiction, but if you knock out this one area, it appears to wipe out the behavior,” said Dr. Antoine Bechara, a senior author of the new paper. The patients’ desire to eat, by contrast, was intact. This suggests that the insula is critical for behaviors whose bodily effects become pleasurable because they are learned, like cigarette smoking.

The insula has widely distributed connections, both in the cortex and subcortical areas, like the brain stem, that maintain heart rate, blood pressure and body temperature. It would appear that it integrates signals from these “lower brain” areas, so that the conscious brain can interpret them as a coherent emotion. This could explain why cravings are physical, and so hard to shake.

Other researchers have advised that a degree of caution should be exercised: “One has to be careful not to extrapolate too much based on brain injuries to what’s going on in all addictive behavior, in healthy brains,” said Dr. Martin Paulus, a psychiatric researcher at the University of California, San Diego. However the study “opens up a whole new way to think about addiction.”

I found this article fascinating for two reasons:
  • Brain research has come on in leaps and bounds since my brief foray into neurophysiology as a student back in the early/mid 80s.
  • I was a 30 a day smoker for over two decades. Until I quit five years ago (and put on a shed load of weight I haven’t yet lost)
While nobody would suggest that brain damage is an effective means to quit the smoking, hopefully future research on the insula will give rise to new and effective treatments for smokers and perhaps other addicts.

11 comments:

Elizabeth-W said...

Okay, so if it's about behaviors whose bodily effects become pleasurable because they are learned, what are the other things that could be? Sex? All the other drugs/alcohol? Gambling maybe not? What say you?
Also, how did you quit? Cold turkey or patches or something else? And finally, is smoking appealing to you, even now? How often now do you get a craving, if so and what triggers the craving?
Did you know the average person quits cigs 7 times before quitting for good? The first couple are usually just what I call "pauses", but then typically each abstinent period has a longer duration.
Thanks for sharing. I'll look for it in the paper tomorrow.

jams o donnell said...

Good question Elizabeth.. It would seem that the brain takes a series of physiological responses, brings them together and the higher cortex processes them as a pleasurable experience (well duh O'donnell!) the physiological repsonse to the absence creates the craving (again I am stating the blindingly obvious!)

20 odd years back science more or less had "here be dragons" signs over the brain for all they really knew about it. There is a long, long way to go but this strikes me as an important piece of research, not just because it may provide effective ant smoking or other anti addiction therapies but because it nudges our understanding of how that thing in our head works a little bit forward.

As for giving up the cigs it took me more than seven goes. I had many attempts from the mid 80s on.. I finally smoked my last one in December 2001 and used Nicotine gum (until it lifted several fillings!) and then lozenges. Even now each and everyone of them seems in my mind to float down from heaven on wings of angels - luckily all I need is to smell one to put me off..

littlebitofsonshine said...

thanks Jams .You did not have to i did not do it to make someone do as i do i did it cause you have good reads .Be safe walk in peace allways
Sonshine

beakerkin said...

Well this may lead to all types of cures. I might even live to see the time when I can walk certain locals without the locals smoking Bob Marley joints uptown.

jams o donnell said...

You never know Beakerkin!

elasticwaistbandlady said...

Brain injury may cause smokers to quit? Hmmmmm. I guess my mom and former smoker addict dad would still be married if she would have just hauled off and popped him a good one upside his head!
(Smoking was a contentious issue in their very brief marriage.)

jams o donnell said...

I am surprised the not wife didn't do the same to meI was a smoker from 1970 to 2001.. But I was forced to smoke out the back after a while!

Roger B. said...

Like you I was a heavy smoker for nearly 20 years. I gave up 12 years ago this February.

What triggered me to give up was hearing my GP say, "You realise this can lead to amputation"

I too found that nicotine gum helped me break the habit.

jams o donnell said...

Ach Roger those are words that would focues any mind towards giving up. I bet it still wwasn't easy though!

Roger B. said...

Thankfully my GP was very supportive and helpful.

jams o donnell said...

THat is good to know Roger..