MOTOR SYSTEMS COMPARATIVE STUDY

本提案描述了一系列行为、解剖学 和神经组织化学实验旨在评估 控制爬行动物运动的神经系统， 凯门鳄。 凯门鳄被选为动物 模型，因为爬行动物的运动系统比这个简单 哺乳动物。 没有直接相当于哺乳动物的运动 皮层存在于爬行动物中，但精确的运动和 尽管如此，协调仍然是行为技能的一部分 这些物种。 试点工作表明两个神经系统，都 源自古纹状体或基底神经节，参与 该物种复杂运动的控制。 第一个 这些源自苍白球并表达运动 主要通过视顶盖发挥作用。 另一个是源自 腹侧苍白球中的神经元并投射到部分 传入运动神经元池的网状结构，例如 三叉神经运动核。 运动行为的新理论 爬行动物是先进的，认为苍白球途径 控制方向和构造介导的行为，而 源自腹侧苍白球控制精度的通路 运动，尤其是下巴和嘴部区域的运动。 这些 系统在解剖学和化学上是不同的。 苍白球 神经元利用 LANT6 和 GABA 作为神经递质，而 腹侧苍白球区含有许多胆碱能神经元。 提出实验来检验假设并进一步 评估化学、解剖学和行为的相关性 两个系统。

The present proposal describes a series of behavioral, anatomical and neurohistochemical experiments designed to evaluate the neural systems underlying the control of movement in the reptile, Caiman crocodilus. Caiman crocodilus was selected as an animal model because the motor system of reptiles is simpler than that of mammals. No direct equivalent of the mammalian motor cortex is present in reptiles, yet precision movement and coordination are nevertheless part of the behavioral repertoire of these species. Pilot work indicates that two neural systems, both derived from the paleostriatum, or basal ganglia, are involved in the control of complex movement in this species. The first of these is derived from the globus pallidus and expresses motor functions largely via the optic tectum. The other is derived from neurons in the ventral pallidum and projects upon portions of the reticular formation afferent to motor neuron pools such as the trigeminal motor nucleus. A new theory of motor behavior in reptiles is advanced which holds that pallidofugal pathways control orientation and tectally mediated behaviors, while the pathways derived from the ventral pallidum control precision movement, particularly of the jaws and mouth region. These systems are anatomically and chemically distinct. Pallidofugal neurons utilize LANT6 and GABA as neurotransmitters while the ventral pallidal region contains many cholinergic neurons. Experiments are proposed to test hypotheses and to further evaluate the chemical, anatomical and behavioral correlates of both systems.