At the level of the anterior commissure, labeled axons from the MOB formed a bundle of fine, beaded fibers occupying the most superficial portion (sublayer IA) of the olfactory tubercle, cortex–amygdala transition zone, and piriform cortex (Fig. 1C). [...] apart from the dense terminal field in sublayer IA, some beaded fibers could be observed in layer II of the cortex–amygdala transition zone (arrowheads in Fig. 1D). Collator note: Fig 1C, Swanson Atlas Levels 19-21, mid-rostrocaudal part of the PIR.

Caudally, varicose fibers occupied sublayer IA of the piriform cortex (not shown), cortex–amygdala transition zone, the anterior cortical amygdaloid nucleus, the nucleus of the lateral olfactory tract, and the ventral anterior amygdaloid area (Fig. 1E). Collator note: Swanson Atlas Levels 22-24.

Finally, fibers reached the caudal piriform and entorhinal cortices (not shown) and sublayer IA of the posterolateral cortical amygdaloid nucleus (Fig. 1I), where they formed a terminal field (Fig. 1J).