Is the Weber test supposed to lateralize sound?

Weber Test Lateralization

Yes, the Weber test is supposed to lateralize in the presence of hearing loss—either to the affected ear in conductive hearing loss or to the unaffected ear in sensorineural hearing loss. 1, 2

Normal Weber Test Response

• In individuals with normal bilateral hearing, the sound should be heard at midline or "everywhere" when a 256 or 512 Hz tuning fork is placed at the midline of the forehead or on maxillary teeth 1, 2
• The mean air conduction difference between ears in normal hearing is only 1.4 dB, and lateralization typically occurs at a difference of 2.5 dB or greater 3
• In 96-98% of ears with bilateral normal hearing or bilateral sensorineural hearing loss, the Weber test remains at midline 3

Lateralization Patterns in Hearing Loss

Conductive Hearing Loss (CHL):

• Sound lateralizes to the affected ear (the ear with conductive pathology) 1, 2
• This occurs because the conductive pathology decreases sound energy mediated by the ossicular chain, which paradoxically increases the resultant sound intensity stimulating the cochlea due to phase differences between osseous and cerebrospinal fluid pathways 4
• In unilateral conductive hearing loss, lateralization to the poorer ear occurs in 63% of cases 3

Sensorineural Hearing Loss (SNHL):

• Sound lateralizes to the unaffected ear (the ear with better hearing) 1, 2
• The Rinne test remains positive (air conduction > bone conduction) in both ears despite the lateralization 2

Clinical Accuracy and Limitations

• The overall accuracy of the Weber test ranges from 81-87% when compared to pure-tone audiometry, with substantial agreement (kappa = 0.63-0.72) 5
• Important caveat: The Weber test has poor diagnostic value for mild conductive hearing loss when the air-bone gap is only 5-35 dB 3
• The test requires a quiet environment to minimize ambient noise interference 2

Special Clinical Scenario

• In longstanding unilateral profound hearing loss (particularly childhood-onset), the Weber test may fail to lateralize despite significant hearing asymmetry 6
• This lack of lateralization is significantly associated with childhood-onset deafness and suggests central adaptation due to chronic unilateral auditory deprivation before the critical period of auditory maturation 6
• This finding may serve as a screening tool for poor cochlear implant candidacy in adults with longstanding single-sided deafness 6

Essential Pre-Test Requirement

• Impacted cerumen must be removed prior to performing the Weber test, as cerumen can cause conductive hearing loss and lead to false lateralization 1, 2