rubro-olivary tract rubro-olivary tract the rubro-olivary tract (rubroolivary fibers) is a tract which connects the inferior olive and the parvocellular red nucleus. rubro-olivary tractdetailsidentifierslatinfibrae rubroolivaresneuronames1419ta98a14.1.04.135 a14.1.06.214ta25870fma77050anatomical terms of neuroanatomy it is hypothesized that it uses both the corticospinal tract and rubrospinal tract.