Health Dictionary
Reliable, easy-to-read patient information on common medical conditions — written in plain language, free of jargon, and grounded in current evidence. Browse the most frequent diagnoses, understand what they mean for everyday life, and learn which steps and questions help you have a focused conversation with your doctor.
Forebrain
Introduction
Overview
Overview
In the anatomy of the brain of vertebrates, the prosencephalon (or forebrain) is the rostral-most portion of the brain. The prosencephalon, the mesencephalon (midbrain), and rhombencephalon (hindbrain) are the three primary portions of the brain during early development of the central nervous system.
- At the five-vesicle stage, the prosencephalon separates into the diencephalon (prethalamus, thalamus, hypothalamus, subthalamus, epithalamus, and pretectum) and the telencephalon (cerebrum). The cerebrum consists of the cerebral cortex, underlying white matter, and the basal ganglia.
When the embryonic prosencephalon fails to divide the brain into two lobes, it results in a condition known as holoprosencephaly.
Additional images
Additional images
-
Embryo between eighteen and twenty-one days. -
Head of chick embryo of about thirty-eight hours’ incubation, viewed from the ventral surface. X 26
Editor-In-Chief: There can be one or more than one Editor-In-Chief. You may also apply to be an Associate Editor-In-Chief of one of the subtopics below. Please mail us [1] to indicate your interest in serving either as an Editor-In-Chief of the entire topic or as an Associate Editor-In-Chief for a subtopic. Please be sure to attach your CV and or biographical sketch.