Acoustic radiation

Auditory radiations
Human auditory pathway. Acoustic radiation is shown as red arrow at center-top.
Details
Identifiers
Latin	radiatio acustica
NeuroNames	2084
TA98	A14.1.08.662 A14.1.09.545
TA2	5587
FMA	62413
Anatomical terms of neuroanatomy [ edit on Wikidata]

Acoustic radiations (also called auditory radiations) are thalamocortical white-matter fiber bundles that convey auditory information from the medial geniculate nucleus of the thalamus to the primary auditory cortex in the temporal lobe of the brain. ^{[1] [2]}

Anatomy

The auditory radiations originate predominantly from relay neurons in the medial geniculate nucleus and terminate mainly in Heschl’s (transverse temporal) gyri (Brodmann areas 41 and 42), which contain the primary auditory cortex. ^{[2] [1]} Along their course, the fibers travel through the deep subcortical white matter, within the internal capsule (especially the sublenticular segment) on their way to the cerebrum. ^[3]

Function

The auditory radiations provide the principal thalamocortical input to primary auditory cortex, supporting conscious perception of sound and forming part of the ascending central auditory pathway from brainstem nuclei through the midbrain and thalamus to cortex. ^{[2] [1]}

Clinical significance

Because auditory information from each ear is represented bilaterally at higher levels of the auditory pathway, unilateral injury to the auditory radiations typically does not cause complete deafness, whereas bilateral interruption of the auditory radiations and/or bilateral cortical injury can produce cortical deafness. ^{[1] [4]} Case reports and series describe cortical hearing loss after sequential or bilateral lesions involving the auditory radiations and primary auditory cortices. ^{[5] [6]}

References

1. Maffei, C; Sarubbo S; Jovicich J (2019). "A Missing Connection: A Review of the Macrostructural Anatomy and Tractography of the Acoustic Radiation". Frontiers in Neuroanatomy. 13 27. doi: 10.3389/fnana.2019.00027 . PMC   6416820 . PMID   30967762.
2. Kretschmann, Hans-Joachim; Weinrich, Wolfgang, eds. (2004). "6.5 Auditory System" (PDF). Cranial Neuroimaging and Clinical Neuroanatomy. Thieme. doi:10.1055/b-0034-56203. ISBN   978-1-58890-145-3 . Retrieved 3 February 2026.
3. Emos, MC; Agarwal S; Khan U (2023). Neuroanatomy, Internal Capsule. StatPearls. StatPearls Publishing. PMID   31194338 . Retrieved 3 February 2026.
4. Silva, G; Gonçalves R; Taveira I; Mouzinho M; Osório R; Nzwalo H (2021). "Stroke-Associated Cortical Deafness: A Systematic Review of Clinical and Radiological Characteristics". Brain Sciences. 11 (11): 1383. doi: 10.3390/brainsci11111383 . PMC   8596458 . PMID   34827309.
5. Brody, RM; Nisbet A; Williams D (2013). "Cortical deafness: a case report and review of the literature". The Laryngoscope. 123 (9): 2278–2284. doi:10.1002/lary.24067. PMID   23921932.
6. Tanaka, Y; Miyazaki M; Albert ML (1991). "'So-called' cortical deafness. Clinical, neurophysiological and radiological observations". Brain. 114 (6): 2385–2401. doi:10.1093/brain/114.6.2385. PMID   1782522.