Finkel L H, Edelman G M
Proc Natl Acad Sci U S A. 1985 Feb;82(4):1291-5. doi: 10.1073/pnas.82.4.1291.
A theoretical account is given for long- and short-term changes in populations of neurons subject to independent rules for pre- and postsynaptic modification. The postsynaptic rule proposes that coactivated heterosynaptic inputs to a neuron alter the states of ion channels at a given synapse, thereby changing the susceptibility of these channels to local biochemical alterations. The resultant change in the population distribution of local channel states affects the postsynaptic potential produced at the synapse by subsequent inputs. This postsynaptic rule applies, in general, to short-term changes at specific individual synapses. In contrast, the presynaptic rule applies in general to long-term changes in the whole neuron, resulting in an altered probability of transmitter release. Because of neuroanatomical constraints, the presynaptic rule affects large numbers of synapses defined by the connectivity of that neuron and distributed nonspecifically over the population. We show that the combined action of the two independent rules upon populations of neurons arrayed in interconnected neuronal groups leads to consistent alterations of the probability of firing of certain circuits while maintaining variability in the response of the population to novel input. This "dual rules" model fulfills the requirements of the theory of neuronal group selection.
本文给出了一个理论解释，用于说明遵循独立的突触前和突触后修饰规则的神经元群体的长期和短期变化。突触后规则提出，神经元共同激活的异突触输入会改变给定突触处离子通道的状态，从而改变这些通道对局部生化改变的敏感性。局部通道状态群体分布的最终变化会影响后续输入在突触处产生的突触后电位。一般来说，这种突触后规则适用于特定单个突触的短期变化。相比之下，突触前规则通常适用于整个神经元的长期变化，导致递质释放概率改变。由于神经解剖学限制，突触前规则影响由该神经元的连接性定义的大量突触，并且在群体中无特定分布。我们表明，这两个独立规则对排列在相互连接的神经元群体中的神经元群体的联合作用，会导致某些回路发放概率的一致改变，同时保持群体对新输入反应的变异性。这种“双规则”模型符合神经元群体选择理论的要求。
