Column of fornix

The column of the fornix is the anterior descending continuation of the body of the fornix. Rostrally, the body bifurcates into right and left columns, which descend into the basal forebrain, anterior to the interventricular foramina.

At the level of the anterior commissure, fibres within each column separate into two major groups:

• Precommissural fibres pass anterior to the anterior commissure and contain the septohippocampal pathway, with additional projections to the forebrain.

• Postcommissural fibres curve posterior to the anterior commissure. They arise principally from the subiculum and project toward the anterior thalamic nuclei, either directly or indirectly through the mammillary bodies.

Thus, the columns of fornix form an important point at which the fornix divides into its major precommissural and postcommissural pathways.