[TA] a narrow, compact fiber bundle that extends along the line of attachment of the roof of the third ventricle to the thalamus on each side and terminates posteriorly in the habenular nucleus. It is composed of fibers originating in the septal area, the anterior perforated substance, the lateral preoptic nucleus, and the medial segment of the globus pallidus. SYN: stria medullaris thalami [TA], stria fornicis, stria ventriculi tertii.