锁阳固精丸丸一天一丸:医学研究："冥想对大脑的益处"

研究人员利用功能性核磁共振成像（fMRI）寻找冥想者与非冥想者的大脑差异，发现冥想似能关闭与遐想、焦虑、精神分裂等精神疾病有关联的大脑区域。报告发表在本周出版的PNAS上。

领导这项研究的耶鲁大学助理教授Judson A. Brewer说，冥想能应用于不同的健康问题，如戒烟、应对癌症，甚至是银屑病。他们用fMRI扫描了有经验的和初学的冥想者的大脑，发现有经验的冥想者能减少名叫默认模式网络(default mode network)的大脑区域的活动，该区域与焦虑、注意力缺陷和多动障碍等精神疾病有关联。研究人员还发现，当大脑默认模式网络活跃起来，自我监控和认知控制有关的区域也会同时活跃，但这一现象仅见于有经验的冥想者而非新手。这可能意味着，冥想能监测和压制心不在焉状态的出现。在病理模式中，这些状态与自闭症和精神分裂症等疾病有关联。

Tuning out: How brains benefit from meditation

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Experienced meditators seem to switch off areas of the brain associated with wandering thoughts, anxiety and some psychiatric disorders such as schizophrenia. Researchers used fMRI scans to determine how the brains of meditators differed from subjects who were not meditating. The areas shaded in blue highlight areas of decreased activity in the brains of meditators. Credit: courtesy of yale

Experienced meditators seem to be able switch off areas of the brain associated with daydreaming as well as psychiatric disorders such as autism and schizophrenia, according to a new brain imaging study by Yale researchers.

Meditation's ability to help people stay focused on the moment has been associated with increased happiness levels, said Judson A. Brewer, assistant professor of psychiatry and lead author of the study published the week of Nov. 21 in the Proceedings of the National Academy of Sciences. Understanding how meditation works will aid investigation into a host of diseases, he said.

"Meditation has been shown to help in variety of health problems, such as helping people quit smoking, cope with cancer, and even prevent psoriasis," Brewer said.

The Yale team conducted functional magnetic resonance imaging scans on both experienced and novice meditators as they practiced three different meditation techniques.

They found that experienced meditators had decreased activity in areas of the brain called the default mode network, which has been implicated in lapses of attention and disorders such as anxiety, attention deficit and hyperactivity disorder, and even the buildup of beta amyloid plaques in Alzheimer's disease. The decrease in activity in this network, consisting of the medial prefrontal and posterior cingulate cortex, was seen in experienced meditators regardless of the type of meditation they were doing.

The scans also showed that when the default mode network was active, brain regions associated with self-monitoring and cognitive control were co-activated in experienced meditators but not novices. This may indicate that meditators are constantly monitoring and suppressing the emergence of "me" thoughts, or mind-wandering. In pathological forms, these states are associated with diseases such as autism and schizophrenia.

The meditators did this both during meditation, and also when just resting — not being told to do anything in particular. This may indicate that meditators have developed a "new" default mode in which there is more present-centered awareness, and less "self"-centered, say the researchers.

"Meditation's ability to help people stay in the moment has been part of philosophical and contemplative practices for thousands of years," Brewer said. "Conversely, the hallmarks of many forms of mental illness is a preoccupation with one's own thoughts, a condition meditation seems to affect. This gives us some nice cues as to the neural mechanisms of how it might be working clinically."

Provided by Yale University

"Tuning out: How brains benefit from meditation." November 21st, 2011. http://medicalxpress.com/news/2011-11-tuning-brains-benefit-meditation.html