n***d
发帖数: 8857 | 1 有个疑问总是挥之不去，问一问诸位行家
wiki上的原话：
Electrical stimulation of the VTA or its output pathways can itself serve as
a potent reward: animals will quickly learn to press a lever if it results
in stimulation of dopamine release, and often will continue pressing the
lever for a long time, at steadily increasing rates.
。。。
there has been a great deal of dispute about whether the function of
dopamine should be described as reward
我想问这个试验有个开关给小老鼠注射一点dopamine, 小老鼠会一直去动这个开关以得
到更多dopamine. 如果dopamine不是rewards, 为什么它还一直要更多dopamine呢? | k******n
发帖数: 253 | | w*****u
发帖数: 13 | 3 我的理解是dopamine对reward行为有影响是没有疑问的事情。但是这种影响是怎么产生
的？是dopaminergic neurons是直接导致了reward，还是说dopaminergic neurons处于
调控回路，控制了reward的强度？这是还没有定论的事情。从分子角度想，reward本身
就是一个很复杂的事情。reward可以出现在很不一样的时间尺度上，说明事情应该比一
种单一的分子所引发的故事要复杂得多。 | w******y
发帖数: 4871 | 4 注射Dopamine?原作的试验是注射dopamin的妈？
as
results
【在 n***d 的大作中提到】
: 有个疑问总是挥之不去，问一问诸位行家
: wiki上的原话：
: Electrical stimulation of the VTA or its output pathways can itself serve as
: a potent reward: animals will quickly learn to press a lever if it results
: in stimulation of dopamine release, and often will continue pressing the
: lever for a long time, at steadily increasing rates.
: 。。。
: there has been a great deal of dispute about whether the function of
: dopamine should be described as reward
: 我想问这个试验有个开关给小老鼠注射一点dopamine, 小老鼠会一直去动这个开关以得
| J***b
发帖数: 76 | 5 The effect of dopamine on animal behaviors seems very complicated. Dopamine
may via D1 receptors stimulate "Go" neurons in the striatum to facilitate
the section of "Go" action in rewarding behaviors;simultaneously via D2
receptor suppress "No-Go" neurons to inhibit the section of "No-Go" actions.
So the net effect is "Go". This might be why dopamine is so powerful,
although none of dopamine receptors are ion channels. These receptors do not
mediate fast synaptic transmission.
However,naturally dopamine release is under control. VTA dopamine neurons
express D2 auto-receptors, which are inhibitory. So an increase in the
firing rate of dopamine neurons leads to an increase in dopamine release in
the VTA, an increase in the activity of D2 auoreceptors, and eventually a
reduction of the firing rate. This is negative feedback.
as
results
【在 n***d 的大作中提到】
: 有个疑问总是挥之不去，问一问诸位行家
: wiki上的原话：
: Electrical stimulation of the VTA or its output pathways can itself serve as
: a potent reward: animals will quickly learn to press a lever if it results
: in stimulation of dopamine release, and often will continue pressing the
: lever for a long time, at steadily increasing rates.
: 。。。
: there has been a great deal of dispute about whether the function of
: dopamine should be described as reward
: 我想问这个试验有个开关给小老鼠注射一点dopamine, 小老鼠会一直去动这个开关以得
| m***i
发帖数: 2013 | 6 Phasic firing in dopaminergic neurons is sufficient for behavioral
conditioning.
http://www.ncbi.nlm.nih.gov/pubmed/19389999 |
|
