stria medullaris of thalamus stria medullaris of thalamus the stria medullaris is a part of the epithalamus. it is a fiber bundle containing afferent fibers from the septal nuclei, lateral preoptico-hypothalamic region, and anterior thalamic nuclei to the habenula. it forms a horizontal ridge on the medial surface of the thalamus, and is found on the border between dorsal and medial surfaces of thalamus. superior and lateral to habenular trigone. stria medullaris of thalamusstria medullaris highlighted in red over the thalamus. posterior to the thalamus, the highlighted portion is the pineal glanddetailsidentifierslatinstria medullaris thalamicaneuronames298neurolex idbirnlex_1066ta98a14.1.08.106ta25747fma62080anatomical terms of neuroanatomy it projects to the habenular nuclei, from anterior perforated substance and hypothalamus, to habenular trigone, to habenular commissure, to habenular nucleus.