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This article attempts to provide definitions to a number of anatomical terminology, definitions and abbreviations, pertinent to the description of the Central Nervous System, particularly in humans. ==Anatomical localisation== (詳細はCNS, such as a fish or lizard. In such animals the terms "rostral", "caudal", "ventral" and "dorsal" mean respectively towards the rostrum, towards the tail, towards the belly and towards the back. For a full discussion of those terms, see anatomical terms of location. For many purposes of anatomical description, positions and directions are relative to the standard anatomical planes and axes. Such reference to the anatomical planes and axes is called the stereotactic approach. However, in humans and most other primates the axis of the CNS is bent and the face (rostrum) is no longer at one end of the rostro-caudal axis of the body. The erect human posture demands modifications of the terms and meanings of the descriptions that apply to most vertebrates, but even greater compromises are necessary in describing the central nervous system. The planes defining the anatomical localisation of the human brain are similar to those that apply to the body, but with certain major differences that reflect the distortion of the brains of the Hominidae in their adaptation to a bipedal way of life. These are shown in the accompanying illustrations and annotations. In particular the anatomical planes and axes that apply to most vertebrate nervous systems need considerable modification before they can be of use in describing the human brain. For example ''in reference to the human brain'', "rostral" still means "towards the face", or at any rate, the interior of the cranial cavity just behind the face. However, in the brain "caudal" means not "towards the tail", but "towards the back of the cranial cavity". Alternative terms for this rostro-caudal axis of the brain include medial or antero-posterior axis. "Dorsal" means "in the direction away from the spinal cord i.e. in the direction of the roof of the cranial cavity". "Ventral" means downwards towards floor of the cranial cavity and thence to the body. They lie on the superior-inferior or Dorsoventral axis. The third axis passes through the ears, and is called the left-right, or lateral axis. These three axes of the human brain match the three planes within which they lie, even though the terms for the planes have not been changed from the terms for the bodily planes. The most commonly used reference planes are: :Axial, the plane that is horizontal and parallel to the axial plane of the body in the standard anatomical position. It contains (and thus is defined by) the lateral and the medial axes of the brain. :Coronal, a vertical plane that passes through both ears, and contains the lateral and dorsoventral axes. :Sagittal, a vertical plane that passes from between the nostrils, and between the cerebral hemispheres, dividing the brain into left and right halves. It contains the dorsoventral and medial axes of the brain. A parasagittal plane is any plane parallel to the sagittal plane. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Anatomical terms of neuroanatomy」の詳細全文を読む スポンサード リンク
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