part of olfactory tract anterior olfactory nucleus A portion of the forebrain of vertebrates. It is found behind the olfactory bulb and in front of the piriform cortex (laterally) and olfactory tubercle (medially) in a region often referred to as the olfactory peduncle or retrobulbar area. The peduncle contains the anterior olfactory nucleus (AON) as well as two other much smaller regions, the tenia tecta (or dorsal hippocampal rudiment) and the dorsal peduncular cortex. AON BTO:0003649 BrendaTissueOBO anterior olfactory cortex