1. Causes of higher auditory pathway lesions
Auditory nerve
Acoustic neuromas
Acoustic neuritis (inflammation)
Multiple sclerosis
Higher centers
Cerebrovascular accidents
Rh incompatibility
Tumours
Age
Syphilis 1 1

2. Consequences Progressive hearing loss, may be unilateral
Vertigo, tinnitus, headache, vomiting, respiratory symptoms
Speech-understanding problems that are greater than that predicted by degree of hearing loss
In some cases, audiogram may look normal 2 2

3. Auditory processing disorders
Also referred to as central auditory processing disorder (CAPD).
Difficulty processing auditory information in the absence of a concomitant loss of peripheral hearing sensitivity. 3

4. Tests for diagnosing APD
Based on intrinsic and extrinsic redundancy
Example:
Binaural fusion test
Filtered speech tests
Synthetic Sentence Identification with Ipsilateral/Contralateral competing message
Staggered Spondaic Word test
Masking level difference
Time-compressed speech 4