wiki笔记--dorsomedial thalamus（重要的结构，词条内容却很少）--2021/4/18
特别说明：由于文章内容粘贴缘故，最终结果导致文中一些格式会消失，请不要在意，专注于文字内容即可。文中文字大小为“特大”方式突出的部分是我的笔记标识内容，是我格外喜欢，用于推理的基础，括号内的有色文字内容是当时我思考的纪录，这样方便自己和他人直接找到那些曾经标记的内容。当然也不全限于此，灵感所致，所加内容无所不及，唯独不会更改原文内容。
Medial dorsal nucleus
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Not to be confused with Dorsomedial hypothalamic nucleus.
Medial dorsal nucleus
Thalamic nuclei:
MNG = Midline nuclear group
AN = Anterior nuclear group
MD = Medial dorsal nucleus
VNG = Ventral nuclear group
VA = Ventral anterior nucleus
VL = Ventral lateral nucleus
VPL = Ventral posterolateral nucleus
VPM = Ventral posteromedial nucleus
LNG = Lateral nuclear group
PUL = Pulvinar
MTh = Metathalamus
LG = Lateral geniculate nucleus
MG = Medial geniculate nucleus
Thalamic nuclei
Details
Identifiers
Latin
nucleus mediodorsalis thalami
MeSH
D020645
NeuroNames
312
NeuroLex ID
birnlex_1543
TA
A14.1.08.622
FMA
62156
Anatomical terms of neuroanatomy
[edit on Wikidata]
The medial dorsal nucleus (or dorsomedial nucleus of thalamus) is a large nucleus in the thalamus.
It is believed to play a role in memory.[1]
Contents
· 1Structure
· 2Function
· 2.1Pain processing
· 2.2Saccadic efference copy
· 3Clinical significance
· 4Additional images
· 5References
· 6External links
Structure[edit]
It relays inputs from the amygdala and olfactory cortex and projects to the prefrontal cortex and the limbic system and in turn relays them to the prefrontal association cortex. As a result, it plays a crucial role in attention, planning, organization, abstract thinking, multi-tasking, and active memory.[citation needed]
（乐趣与好处。有好处才会有attention，这个状态应该是serotonin对NAcc shell强烈作用使得NAcc shell工作状态低下，从而降低了对VTA和副交感系统的抑制，所以人处于注意集中的状态时交感系统一点都不活跃，同时ventral pallidum也得不到NAcc shell的抑制，那么此时NE system工作状态提升，如果所注意（比如听讲）内容带不来好处，就会因为NE积累而交感系统逐渐兴起，如果所注意内容带来好处，就意味着有持续的serotonin产生来抵消积累的NE，作用在NAcc shell也能得到补充。所以，当保持注意状态一定时间是需要释放一下DA system，释放一下交感系统。导盲犬工作中就是注意集中的状态，导盲犬也需要放松玩闹。所以，能否带来好处是关键。乐趣，是substantia nigra pars compacta的大爆发，其中nucleus accumbens一定不能被抑制。这里给出了一种处于attention状态的原因，NAcc shell被serotonin“抑制”，且所注意的内容能带来好处（也即是serotonin），否则就坐不住了，这种注意状态需要通过课间时间来释放一下DA system。记得上学期间，那些聪明的、学习好的孩子课间都出去玩。我自己有一次初中模考，中间休息的时候在操场疯跑，下一科的理科考试考得就非常好，当时我自己都有点意料之外，因为考完我没有觉得有多好，出成绩后我也想不起来为什么考得这么好。）
The connections of the medial dorsal nucleus have even been used to delineate the prefrontal cortex of the Göttingen minipig brain.[2]
By stereology the number of brain cells in the region has been estimated to around 6.43 million neurons in the adult human brain and 36.3 million glial cells, and with the newborn having quite different numbers: around 11.2 million neurons and 10.6 million glial cells.[3]
Function[edit]
Pain processing[edit]
While both the ventral and medial dorsal nuclei process pain, the medial dorsal nucleus bypasses primary cortices, sending their axons directly to secondary and association cortices. The cells also send axons directly to many parts of the brain, including nuclei of the limbic system such as the lateral nucleus of the amygdala, the anterior cingulate, and the hippocampus. This part of the sensory system, known as the non-classical or extralemniscal system is less accurate, and less detailed in regards to sensory signal analysis. This processing is known colloquially as "fast and dirty" rather than the "slow and accurate" system of classical or lemniscal system. This pathway activates parts of the brain that evoke emotional responses.[citation needed]
Saccadic efference copy[edit]
This nucleus is also presumed to play a role in monitoring internal movements of the eye. Specifically, its function is to relay the information about how the eyes will be moved (efference copy, also known as corollary discharge) from the superior colliculus to the frontal eye fields (FEF) in order to aid the neurons in FEF to change their receptive fields to where the visual stimuli will appear after the saccade.[4]
Clinical significance[edit]
Damage to the medial dorsal nucleus has been associated with Korsakoff's syndrome.[5]
（dorsomedial nucleus of thalamus这么重要的结构，在这个词条中居然没有一个有用的信息，也没有明确反映结构和连接关系的信息，可见现在的研究水平是多么低，其实也难怪，只有primates具有dorsomedial nucleus of thalamus和granular prefrontal cortex，在我看来，能搞懂dorsomedial nucleus of thalamus的结构和功能，就基本解决了人类独有的复杂行为和智力。唉，最重要的结构，最关键的结构，往往是信息最少的。不过我从其他地方了解到一些关键信息，比如dorsomedial nucleus of thalamus与prefrontal cortex之间存在reciprocal connection, prefrontal cortex接受初级视觉皮层的投射，自身还投射到parietal cortex where is also the target of vision information(当你看黑白电视的时候，parietal cortex接受的视觉信息就少了来自prefrontal cortex的颜色，所以感觉起来不是那么开心，不过你还是可以通过常识来兴奋dorsomedial nucleus of thalamus，从而“脑补”那些缺失的颜色)；不需要外界信息就可以自发放电的ventral pallidum投射抑制轴突到dorsomedial nucleus of thalamus；amygdala投射到dorsomedial nucleus of thalamus；pontine ACh system投射到dorsomedial nucleus of thalamus；我的一个预测性假设（其实是我从另一个wiki词条中看到的，但是后来就再也找不到了，就只能成为假设）是temporal cortex投射到dorsomedial nucleus of thalamus。其注意，这里amygdala（代表NE system）、pontine ACh system和ventral pallidum（代表DA system）轮番对dorsomedial nucleus of thalamus影响，这对应着起码三种不同兴奋dorsomedial nucleus of thalamus的模式，进而三种不同兴奋prefrontal cortex的模式，也对应了起码的三种不同的行为状态，这才是揭秘人类独有的复杂行为和智力的关键，对应着规则行为、目的行为和兴趣行为。这也是我可以直接用观察的行为来证明我的理论的一个途径。而语言是temporal cortex投射dorsomedial nucleus of thalamus互射prefrontal cortex的结构记忆，也是我可以直接用观察的行为来证明我的理论的一个途径。就先写这些吧，我很想写hippocampus--cingulate cortex circuit，这个更重要，但是内容更多更复杂，我不知道最近还能否有如此多的、不受打扰的时间，去纪录更复杂的wiki笔记。还有就是最近新发现的状态原理，涉及habenular cortex、diagonal band of Broca、interpeduncular nucleus、periaqueductal gray、pedunculopontine nucleus等等，对应着大脑最隐秘的思维状态，也就是说基本没有外在表现的、基本不留下记忆的、只留下思维结果的思维状态，包含清醒状态下和REM睡眠状态下的神经工作机制。）
