The acoustic radiations or auditory radiations are structures found in the brain, in the ventral cochlear pathway, a part of the auditory system. Acoustic radiation arising in the medial geniculate nucleus and end in primary auditory cortex (transverse temporal gyri).Lesions to the auditory radiations could be a cause of cortical deafness. The acoustic radiations or auditory radiations are structures found in the brain, in the ventral cochlear pathway, a part of the auditory system. Acoustic radiation arising in the medial geniculate nucleus and end in primary auditory cortex (transverse temporal gyri).Lesions to the auditory radiations could be a cause of cortical deafness.