Separate and direct connections linking the sound-processing centers on both sides of the brain

Commissural neurons in the central nucleus of the inferior colliculus send projections to corresponding frequency-band laminae in the opposite auditory cortices.

• The study reveals a divergent projection from commissural neurons to the central nucleus and both dorsal and lateral cortices across the midbrain.
• The density of these projections is higher at locations corresponding to the position of the tracer injection, indicating a point-to-point wiring pattern.
• Two distinct populations of neurons may exist in the dorsal cortex: one projecting specifically to the central nucleus and the other more diffusely to the dorsal cortex.
• Neurons in the lateral cortex contribute weakly to the commissural pathway.
• The observed point-to-point connections facilitate interactions between specific regions of frequency-band laminae, while the divergent projections may aid in broader integration.

Simplified