Cortico-cortical connections reorganize in hamsters after neonatal transection of the callosal bridge.

Neonatal hamsters were subjected to transection of the callosal bridge. Later examination of the brains showed complete or partial absence of the corpus callosum and an anomalous bilateral longitudinal bundle of fibers. In addition, aberrant commissural fibers were seen to connect heterotopically the parietal cortex with the contralateral frontal cortex through a callosal remnant over the septum, and the olfactory cortex with the opposite frontal and parietal cortices through the anterior commissure.