美國科學家研究發(fā)現(xiàn),，大腦中一個名為島葉的區(qū)域受損后，煙民的煙癮就會消失,。但科學家同時提醒人們,，千萬不要因此將損傷大腦作為戒煙的方法,。
美國南加州大學的安托萬·貝沙拉等人２５日在《科學》雜志上介紹說，島葉又稱腦島,，位于大腦外側(cè)裂深處,，約一個硬幣大。他們最初注意到這一特殊區(qū)域是因為一位患者中風前后的迥異表現(xiàn),。這位煙民中風前每天要抽兩包煙,，但在中風導(dǎo)致島葉受損后卻一支煙也不抽，說是“身體忘記了抽煙的欲望”,。
科學家因此推測,，對島葉的損害有可能幫助戒煙。他們于是選取了１９名島葉受損和５０名大腦其他部位受損的吸煙者進行進一步研究,。這些人在腦部受損前都有兩年以上的吸煙史,，每天吸煙都超過５支。研究結(jié)果發(fā)現(xiàn),，島葉受損的１９人中有１３人成功戒煙,，至今沒有反復(fù)；其他５０人中有個別人成功戒煙,?？傮w來看，島葉受損者戒煙最容易,。
貝沙拉認為,，新發(fā)現(xiàn)具有巨大的藥理學潛力。但他同時強調(diào),，由于人體許多日常功能都與島葉有關(guān),，在根據(jù)這一發(fā)現(xiàn)研究戒煙新方法時應(yīng)避免殃及人的食欲等正常機能。
此前已有研究發(fā)現(xiàn),，島葉會被某些與致癮物質(zhì)有關(guān)的信號激活,，比如看到有人吸毒時，島葉就會有所反應(yīng),。但與大腦其他部位相比,，科學家以前在研究致癮物質(zhì)時很少關(guān)注島葉。
英文原文：
Area in Brain Key to Quit Smoking?
Damage to Specific Brain Area Banishes Smoking Addiction Urge, Study Shows
Jan. 16, 2007 -- A strokestroke patient who quit smokingquit smoking because his "body forgot the urge to smoke" may hold the key that unlocks the chains of addiction.
That key appears to be a region on the right and left sides of the brain called the insula.
The insula is thought to control conscious urges. One study showed that drug addicts who relapse have high-level insula activity during decision-making tasks.
"What happens to addictions when there's damage to the insula?" wondered Antoine Bechara, PhD, of the universities of Southern California and Iowa.
To find out, Bechara, along with Hanna Damasio of USC and other colleagues, compared people who quit smoking after injury to the insula with those who quit after suffering brain damage that did not include the insula. Not all of the patients had strokes.
Twelve of 13 patients with damage to the insula quit smoking soon after their brain damage, never started smoking again, found it easy to quit, and, after quitting, never again felt the urge to smoke. In other words, they lost their smoking addiction.
Loss of smoking addiction occurred in only four of 19 patients without insula damage.
The experience of the patient who said his body forgot the urge to smoke "suggests that the insula plays a role in the feeling that smoking is a bodily need," Bechara and colleagues conclude.
None of the insula-damaged patients who lost their smoking addiction lost their desire for food or ate less.
This suggests that insula damage does not make a person lose fundamental urges. Instead, the researchers suggest, insula damage affects only "learned pleasures."
This means the insula may also control other kinds of addiction.
Brain surgery isn't a solution to cigarette smoking or other addictions. But, Bechara says, the insula could be a target for new drug treatments.
"There is a lot of potential for pharmacological developments," he says in a news release.
Bechara and colleagues report their findings in the Jan. 26 issue of Science.
