Glossary of anatomical terminology, definitions and abbreviations

This is a glossary of anatomical terminology, definitions and abbreviations pertinent to the description of the Central Nervous System.

Anatomical localisation
The terms used for anatomical localisation are best understood if we think of an animal with a straight CNS, like a lizard. Here the terms "rostral", "caudal", "ventral" and "dorsal" mean respectively towards the rostrum, towards the tail, towards the belly and towards the back. In humans and other primates, the axis of the CNS is bent, and the face (the rostrum) is no longer at one end of the rostro-caudal axis. So, for the brain, "caudal" means towards the back of the head, "ventral" means towards the body, and "dorsal" means towards the top of the head.

It is common to represent the complex 3-D organisation of the CNS through slices, which is called the stereotactic approach (stereo from solid object and tactic from tactus, touch). The most common orientation for slices are Axial, a horizontal slice, Coronal, a vertical slice that can show both ears, and Parasagittal, a vertical slice that can show from the nose to the back of the head. A Sagittal slice is the slice that divides the head in two equal left and right sides. A Parasagittal slice is then any slice parallel to the Sagittal slice.

A

 * AC: Anterior Commissure.


 * Afferent: An afferent fibre is a fibre originating at the present point. For example a striatal afferent is an afferent originating at the striatum. See Efferent.


 * Anatomy: The determination of the regions in an organism that are to be considered its "parts". From the Latin anatomia, dissection, from the Greek, anatome, where ana means up, and temnein means to cut.


 * Annectent Gyrus: A small gyrus hidden in the depth of a sulcus. Also known as transition gyrus. See Gyrus, Sulcus.


 * Axial: A plane orthogonal to the superior-inferior axis. In the brain, it shows left and right, face and back of the head. Equivalent to Horizontal. See Anatomical localisation.


 * CalcS: Calcarine Sulcus.


 * Caudal: Towards the tail. See Anatomical localisation.


 * CC: Corpus Callosum.


 * CingS: Cingulate Sulcus.


 * Commissure: A groupe of fibres that cross the sagittal plane.


 * Contralateral: At the opposite side.


 * Coronal: A plane orthogonal to the anterior-posterior axis. In the brain, it shows left and right, the top of the head and the neck.


 * CS: Central Sulcus.

D

 * Dorsal: Towards the back (dorsum). See Anatomical localisation.
 * DTI: Diffusion tensor imaging.
 * DWI: Diffusion weighted imaging.

E

 * Efferent: An efferent fibre is a fibre that arrives at the present point. For example, a cortical efferent is a fibre coming from somewhere else, and arriving to the cortex. See also Afferent.
 * EPI: Echo planar imaging.

F

 * Fissure: A deep groove produced by opercularisation like the Sylvian fissure, or by the differentiation of the telencephalic vesicles like the Medial (Interhemispheric) Fissure.


 * Fundus: pl Fundi. The bottom of an inward fold. See Sulcal Fundus, Sulcus.

G

 * Gyral Crown: The top of a Gyrus. See Sulcal Wall, Sulcal Fundus, Gyrus, Sulcus.


 * Gyrus: pl. Gyri. An outward fold (a hill), as for example the gyri of the cerebellar or cerebral cortex. Important gyri are the precentral and postcentral gyri, for example.

H

 * Horizontal: A plane orthogonal to the superior-inferior axis. In the brain, it shows left and right, face and back of the head. Equivalent to Axial. See Anatomical localisation.

I

 * IFG: Inferior Frontal Gyrus.
 * IFS: Inferior Frontal Sulcus.
 * IPS: Intraparietal Sulcus.
 * Ipsilateral: At the same side. See Contralateral.
 * ITS: Inferior Temporal Sulcus.

L

 * Lacrimal Bone: A skull bone

M

 * Mesencephalic duct: aka Cerebral aqueduct or Aqueduct of Sylvius, is part of the liquidean system of the CNS.


 * Medial: At the middle. For example, the medial cortex is the cortex near the plane that divides left and right hemispheres;


 * Mesial: Directed towards the middle.


 * MRI: Magnetic Resonance Imaging.

O
oculo- eye
 * Operculum: pl. Opercula.

P

 * Parasagittal: A plane parallel to the sagittal plane (which divides left and right sides). See Sagittal, Anatomical localisation.
 * PC: Posterior Commissure.
 * postCS: Postcentral Sulcus.
 * preCS: Precentral Sulcus.
 * Pu: Putamen.

R

 * Rostral: Towards the face. See Anatomical localisation.

S

 * Sagittal: A plane that divides exactly the left and right sides. See Parasagittal, Anatomical localisation.


 * SFS: Superior Frontal Sulcus.


 * STS: Superior Temporal Sulcus.


 * Sulcal Fundus: pl Sulcal Fundi. The bottom of an inward fold. See Sulcus.


 * Sulcal Wall: One of the two sides of a sulcus (an inward fold). See Sulcus.


 * Sulcus: pl. Sulci. An inward fold (a valley), as for example the central and calcarine sulci of the cerebral cortex. Examples of important sulci are the central sulcus (CS) and the calcarine sulcus (CalcS). See also Fissure.

T

 * Th: Thalamus.
 * Transition Gyrus: A small gyrus hidden in the depth of a sulcus. Also known as annectent gyrus. See Gyrus, Sulcus.

V

 * Ventral: Towards the belly. See Anatomical localisation.

Z
Zygomatic arch: Forms the Jaw bone. :)