The term olfactory trigone refers to a triangular area on the ventral surface of the forebrain of the human ( Carpenter-1983 ). It is a superficial feature, the floor of which is the olfactory tubercle (also known in the human as the anterior perforated substance). The peak of the triangle faces anteriorly and is formed by what early dissections suggested to be a split of the olfactory tract into medial and lateral olfactory tract. Later studies showed that the fold of tissue presumed to be a medial olfactory tract did not, in fact, contain neuronal axons. The lateral structure is now recognized as the caudal continuation of the olfactory tract ( Price-1990 ).