Sagittal | Brain Parts

Sumit Karia MD Ashley Davidoff MD

Introduction

There are many places to start the study of the brain, but we have decided to start with the classical lateral view, and to define the main vectors in this view, and thereafter superimpose the vectors on a brain specimen.

The Basic Structure of the Brain from its LAteral Aspect

The Brain at its Simplest

The stick diagram divides the brain into a relatively long almost horizontal component, and a relatively short almost vertical component. Anatomically the horizontal component is called the forebrain, and the vertical component will make up the midbrain (orange) and hind brain (salmon) and extend ino the spinal cord

The Sagital Conceptual Vectors Overlying an External Lateral View of the Brain

The vectors of the brain from a side view are superimposed on a specimen of the brain, showing a long anteroposterior vector of the forebrain (light green) and a shorter more vertical vector consisting of the midbrain (orange) and the hind brain (salmon pink)

Major Parts of the Brain

This artistic rendition of the brain reflects the vectors of the major parts of the brain with the stick diagram overlaid on a sagittal external view of the brain. In the stick diagram, the forebrain has now been divided into the frontal lobe (bright green), parietal lobe (light mauve) occipital lobe (purple) and temporal lobe (red). The midbrain is represented in orange, and the hind brain consists of the pons (pink) medulla (salmon) and the cerebellum (maroon)

Artistic rendition Reflecting the Concept of Inverted C -Shaped Rings

The shape of the brain in general is an ovoid. As one goes beyond the surface in the sagittal plane, the brain can be viewed as a series of inverted c shaped structures.

The Forebrain

A series of C rings

The forebrain has most of its components aligned in a series of c-shaped rings starting from the outer cortex and advancing through a series of smaller inner rings with each intimately connected to the others. The thalamus apeears diagramatically as the center of these rings as seen from the sagittal view

MRI of the Midbrain

The midbrain is an almost rectangular structure that bridges the forebrain and hindbrain. It is the smallest of the 3 major components of the brain

Conceptual Framework of the Hindbrain

The hindbrain conceptually consists of 3 ovoids The pons is anterior and superior (light pink), the medulla is smaller and is anterior and inferior, and the cerebellum is the largest and is posterior.

The Concept In Vivo

The 3 ovoids are situated in the posterior cranial fossa the pons is anterior and superior (light pink), the medulla is smaller and is anterior and inferior, and the cerebellum is the largest and is posterior.