[分享][讨论]痛是一种情绪？

网上看见一点东西，但我不大会翻译，原文转来：

QUOTE:

1、A new view of pain as a homeostatic emotion   （一种新的观点：痛是一种内部平衡的情绪）

A. D. (Bud) Craig

Atkinson Pain Research Laboratory, Barrow Neurological Institute, 350 West Thomas Road, Phoenix, AZ 85013, USA

Available online 16 April 2003.

http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6T0V-48CNNYK-1&_user=10&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=

d95cba81c540b61bf35646474b4a598c

Abstract

Pain is conventionally viewed as a pattern of convergent activity within the somatosensory system that represents the exteroceptive sense of touch. Accumulating functional, anatomical and imaging findings indicate that pain is generated by specific sensory channels that ascend in a central homeostatic afferent pathway. Phylogenetically new thalamocortical projections in primates provide a sensory image of the physiological condition of the body and, in addition, direct activation of limbic motor cortex. These findings indicate that the human feeling of pain is both a distinct sensation and a motivation – that is, a specific emotion that reflects homeostatic behavioral drive（人类的痛感受是由两者构成：一种明显的感觉，和一种动机——即一种表现自我平衡行为的驱力）, similar to temperature, itch, hunger and thirst.

Article Outline

1. Homeostasis maintains the body
     

2. Homeostatic emotions drive behavior
     

3. Pain is a homeostatic emotion
      （疼痛是一种稳态情绪）

4. A homeostatic afferent pathway originating in lamina I
      

4.1. Spinal components
       

4.2. Homeostatic afferent integration
       

4.3. Distinct sensory channels
       

4.4. Direct input to primate forebrain

5. Physiological evidence that burning pain is a homeostatic feeling
     

6. Concluding remarks
     

[此贴子已经被作者于2008-10-28 8:56:10编辑过]

2、
Pain Encoding in the Human Forebrain: Binary and Analog Exteroceptive Channels
   

The Journal of Neuroscience, July 21, 2004, 24(29):6540-6544; doi:10.1523/JNEUROSCI.1630-04.2004

http://meagherlab.tamu.edu/M-Meagher/%20Health%20Psyc%20630/Readings%20630/Pain%20mech%20read/Craig%2003%20pain%20emotion.pdf

Abstract

The neuronal system signaling pain has often been characterized as a labeled line consisting of neurons in the pain-signaling pathway to the brain [spinothalamic tract (STT)] that respond only to painful stimuli. It has been proposed recently that the STT contains a series of analog labeled lines, each signaling a different aspect of the internal state of the body (interoception)(e.g., visceral-cold-itch sensations). In this view, pain is the unpleasant emotion produced by disequilibrium of the internal state（疼痛是不平衡的内部状态所产生的不愉快情绪）. We now show that stimulation of an STT receiving zone in awake humans (66 patients) produces two different responses.The first is a binary response signaling the presence of painful stimuli. The second is an analog response in which nonpainful and painful sensations are graded with intensity of the stimulus.Compared with the second pathway, the first was characterized by higher pain ratings and stimulus-evoked sensations covering more of the body surface (projected fields). Both painful responses
to stimulation were described in terms usually applied to external stimuli (exteroception) rather than to internal or emotional phenomena, which were infrequently evoked by stimulation of either pathway. These results are consistent with those of functional imaging studies that have identified brain regions activated in a binary manner by the application of a specific, painful stimulus while increases in stimulus intensity do not produce increased activation. Such binary pain functions could be involved in pain-related alarm-alerting functions, which are independent of stimulus amplitude.

[此贴子已经被作者于2008-11-1 16:16:32编辑过]

这两篇文章当中使用“emotion”时，都没有定义它是什么意思，本人认为并不严格，最好不要当成可以引用的来源。

比如说第一篇里，他认为“痛”与温度、刺痒、饥饿和渴等类似。难道温度也是情绪吗？

在第二篇里也只是一笔带过，大概连编辑都懒得与他计较了。

看到这个国内的研究：

QUOTE:

生理科学进展 >> 2007年38卷4期 >>

第二触觉系统：编码触觉情绪成分的C纤维
华庆平[1,2] 罗非[2]
[1]北京大学神经科学研究所,北京100083 [2]中国科学院心理研究所心理健康重点实验室,北京100101

摘要:过去曾认为,人类触觉信息特异地由大直径有髓（Aβ）神经纤维传导。然而最近的研究表明,哺乳动物皮肤的机械感受器不仅有Aβ纤维分布,还有大量低阈值、低传导速度的小直径无髓（C）神经纤维分布,后者对轻微的非伤害性皮肤变形反应敏感,而对快速的皮肤运动反应微弱。初级传入C纤维投射至脊髓浅层,并与脊髓板层II内的次级感觉神经元形成突触联系,再通过脊髓丘脑束投射至岛叶。功能磁共振（fMRI）研究发现,缓慢移动的触觉刺激可以明显地激活岛叶并引起愉悦感,同时还可以激活眶额叶内与愉悦味觉和嗅觉激活区域邻近的部位。这些反应的性质和所激活的部位说明,C纤维触觉主要与边缘系统的功能有关,编码触觉的情绪成分。 http://www.cqvip.com/QK/90119X/2007004/25723914.html

这是否说明了在痛觉中，大直径有髓神经纤维是传递感觉信息（即这个疼痛的部位和其它机械性感觉），而C神经纤维是传递痛的（一般认为C神经纤维是痛传感器），即那种作为体验的痛。是否这也说明从神经通路上来看，痛是一种情绪，而不是一种感觉。另外，我们知道，C纤维不仅是疼痛传感器，而且也是愉悦传感器。这表明痛和愉悦的体验所反映的很可能只是神经元的某种生理激活状态，任何神经元都会表达这两种生理激活状态，即都能产生愉快或痛（不愉快）的感受。并且这与它们最终在杏仁核所产生的是抑制还是兴奋应该有密切关系。

[此贴子已经被作者于2008-10-27 17:25:26编辑过]

上楼的链接只能看到摘要，谁能搞到全文分享一下？

大点的院校和心理所的学生找全文都应该没问题。

还有中文和英文的相关介绍个一篇：

QUOTE:

英研究发现愉悦神经 称抚摩可降低疼痛感

http://www.39kf.com/focus/lc/sjk/2008-09-16-516726.shtml

 

英国科学家最近发现了一种“愉悦神经”，这种分布在人体皮肤上的独特“装置”可以在受到抚摩时减轻疼痛感。研究人员认为，这一发现有助于开发针对慢性病乃至抑郁症的新式疗法。 “愉悦神经”缓解痛感 据介绍，人体皮肤在受到轻轻的抚摩时，这种神经就会作出反应。它们对诸如母亲对情绪不好的孩子所做的这类反复抚摩、拥抱动作尤其敏感。 英国利物浦大学的弗朗西斯?迈克格伦内教授表示，当皮肤受到刺激而感到疼痛时，通过轻轻抚摩疼痛处四周的“愉悦神经”就可以显著地减轻痛感。这种“愉悦神经”其实属于神经系统中C纤维的一种。目前科学界普遍认为，C纤维是造成皮肤痛觉的神经纤维，但是现在迈克格伦内教授发现，C纤维当中还存在一个可以触发愉悦感的“小团体”。 迈克格伦内说：“我们正在进行的研究发现了C纤维的另一种角色，它们不仅是疼痛传感器，而且也是愉悦传感器。” 拥抱对早产儿尤其重要 迈克格伦内还补充说：“在人体皮肤中还存在另外一种感觉神经纤维来处理愉悦感以及我们熟悉的一些触摸，例如梳理妆扮或者被拥抱等触摸动作。” 越来越多的证据显示，碰触皮肤和对身体温柔的抚摩能够激活局部人体神经系统，因此人们在被所爱的人拥抱或者自己梳理、抚摩自己时都会产生良好感觉。 迈克格伦内告诉记者：“我认为，我们梳理妆扮自己是为了获得好感觉……临床抑郁症的特点之一就是人们不再打理自己，他们停止了照顾自己。” 迈克格伦内说：“没有疼痛感我们就不可能生存。现在我们又开始了解到，假如缺乏愉悦感和满足感，缺乏馈赠别人的行为——例如爱人之间的爱抚、对婴儿的爱抚等，我们也不可能生存。” 据悉，现在医学界已普遍意识到，假如早产儿在出生后就获得了拥抱，那么接下来对其所采取的医疗手段会获得更高疗效，这就是“愉悦神经”在起作用。

Stroking reveals pleasure nerve   http://news.bbc.co.uk/2/hi/science/nature/7610383.stm
By Jenny Carpenter
Science reporter, BBC News

A new touch-sensitive nerve fibre responsible for the sense of pleasure experienced during stroking has been described at a UK conference today.
The nerves tap into a human's reward pathways, and could help explain why we enjoy grooming and a good hug, a neuroscientist has explained.
His team used a stroking machine to reveal the optimal speed and pressure for the most enjoyable caress.
The research was presented at the British Association Science Festival.
Mothers stroke their children, monkeys groom group members, and we all enjoy a massage, but what is it about stroking and rubbing that we find so enjoyable?
"People groom because it feels good," said Professor Francis McGlone, a cognitive neuroscientist at Unilever R&D, but went on to explain that little is known about how we experience the pleasure of touch.
In order to isolate the touch-sensitive nerves responsible for the pleasure experienced during stroking, Professor McGlone designed a "rotary tactile stimulator" - a high-tech stroking machine.
"We have built some very sophisticated equipment, so the stimulus [of stroking] is very repeatable.
"We stroke the skin [of the forearm, foreleg, and face] with a brush at different velocities, and then asked the volunteers to rate how they liked it," he explained.
He also inserted microelectrodes through the skin, into a nerve, to record the neural signals running from the skin to the brain.
"It is like tapping a single phone-line and listening for the chatter that comes down that line," he told the conference.
Feel-good chemicals
By comparing how the neural signals corresponded with how much the volunteers enjoyed the stroking, he was able to pin down people's pleasure to one set of nerves called "C-fibres".
He thinks that the stroking movements are activating C-fibres, which are wired into the rewards systems in the brain, causing the release of feel-good hormones.
Professor McGlone points out that these touch nerves are not responsible for the pleasure experienced from rubbing sexual organs, nor are they found in a person's palms or soles.
"Experiencing pleasure when grappling with tools or walking, would make both task difficult to do with any accuracy," he suggested.
The Liverpool-based researcher showed that stroking speeds of about 5cm per second, while applying 2g of pressure per square cm is optimal, and gave the volunteers most pleasure.
He explained that the pleasure messages are conveyed from the skin to the brain, by similar types of nerve fibres as those that transmit the sensation of pain.
"This is interesting as we often rub a pain to try to alleviate it," he said.
This could explain why the pain experienced by people exposed to a painful thermal stimulus, lessens when the region of the stimulus is simultaneously stroked.
Stroking could be used to treat chronic pain, he suggests.

[此贴子已经被作者于2008-10-28 8:49:10编辑过]

这种C纤维大概是比较新的发现，普通的教材上都没有介绍。

需要多读些论文来理解。

[em25]

痛的本质是一种能兴奋惩罚中枢的特殊刺激。它能部分兴奋主要与惩罚中枢相联系的自主反应系统，并建立记忆联系。为了逃避或减轻惩罚，又会学习获得一系列的思想行为习惯。因而对痛会有情绪反应，同时痛觉反应是遗传与学习的综合。

QUOTE:

以下是引用thinker_jeff在2008-10-29 4:15:00的发言：

这种C纤维大概是比较新的发现，普通的教材上都没有介绍。

需要多读些论文来理解。

[em25]

显然，要辨别痛是感觉还是情绪必须从它的神经通路和活动形式上来看。一般划分是感觉通路是特异的，它的传入经丘脑后直接进入皮层，对皮层的投射是有特定区域的；情绪通路是非特异的，它的传入经丘脑后先进入杏仁核，然后再弥散性地投射到皮层（感觉通路到皮层后也能下行进入杏仁核，但这应该是条件性活动）。因此我认为应该看痛信息经丘脑后是直接进入皮层还是先进入杏仁核。但这里又必须区分感受成分和感觉成分，因为来自身体上的痛觉信号中包括机械性的感觉信息（与痛不痛无关，比如位置信息等）。但自从人们把痛当作一种感觉来研究至今，似乎还没有这种专门的区分。达马西奥参加过的那个实验似乎并没有把痛作为情绪来看待，而只是把情绪作为痛的一种伴随物而不是痛本身，就如情绪伴随在其他认知活动中一样。

找到了克雷格的那篇论文：

Pain as a Homeostatic Emotion.

Pain is an enigmatic feeling from the body, distinct from the classical senses because it is multifaceted (it is a discriminative sensation, an affective motivation, a potent autonomic drive and a reflexive motor stimulus) and because it is inherently variable. Most reviewers, following the introduction of the gate-control theory in 1965, have regarded pain as a sub-modality of cutaneous sensation, or exteroception[1–3]. In this conventional view, pain is represented centrally by convergent somatosensory activity conveyed by wide-dynamic-range cells in the deep dorsal horn of the spinal cord to a modifiable pattern detector in the somatosensory thalamus and cortices.However, this view is contradicted by the observations that neither damage nor stimulation of somatosensory cortices affects pain, and that clinical stimulation of somatosensory thalamus can alleviate chronic pain. Recent converging evidence compels a new, specific view of pain as a homeostatic emotion, akin to temperature, itch, hunger and thirst [4,5]. In this view, pain emerges in primates as a feeling from the body that is generated by specific sensory pathways, within a direct thalamocortical projection that extends the afferent limb of the hierarchical homeostatic system to the cortical level. That is, pain is both an aspect of interoception (the sense of the physiological condition of the body) and a specific behavioral motivation. This striking conceptual shift incorporates the multiple facets of pain into one concrete framework, and it provides sound explanations for pain as both a specific sensation and a variable emotional state. These new findings are summarized after considering the nature of homeostasis.

Homeostasis maintains the body
Homeostasis, as elucidated by Cannon [6], is a dynamic and ongoing process comprising many integrated mechanisms that maintain an optimal balance in the physiological condition of the body, for the purpose of survival. In mammals, these include autonomic, neuroendocrine and behavioral mechanisms. Homeostasis is commonly regarded as maintaining salt, energy, oxygen and water levels, but Cannon recognized that a change in any one condition usually affects several measures and elicits integrated, hierarchically organized homeostatic responses that restore an optimal balance......