A commissure is the location at which two objects abut or are joined. The term is used especially in the fields of anatomy and biology. The most common usage of the term refers to the brain's commissures, of which there are five.

What is commissural surface?

The point or surface where two parts, such as the eyelids, lips, or cardiac valves, join or form a connection.

What do Commissural fibers do?

Commissural fibers connect an area in one hemisphere with an area in the opposite hemisphere. The corpus callosum is the largest set of commissural fibers in the brain and is a pathway of crucial importance to speech-language functions (Fig. 2-10, B).