Distorted Hearing? Hearing Aids as a Screening Tool for ANSD vs APD: Closing Gaps in Reflex and ABR Testing
Hi APD community,
We have had some great discussions lately about auditory neuropathy spectrum disorder (ANSD) and auditory processing disorder (APD). ANSD involves desynchrony in the nerve signal, while APD affects how the brain processes sound. Both can cause similar struggles, such as difficulty understanding speech in noise, which makes them tricky to tell apart.
The gold standard for ruling out ANSD includes auditory brainstem response (ABR) testing and acoustic reflex thresholds. As members here have pointed out, especially Reverse Slope (a.k.a., Dan Schwartz), an ANSD expert, FB admin, electrical engineer, and hearing aid dispenser, in cases of reverse slope hearing loss (where low frequencies are more affected), reflex threshold testing is key for spotting potential neural issues. Unfortunately, many families come to me without this information. Sometimes they only have pass or fail reflex results, and often they have no reflex data at all.
ABR testing is another area with gaps. Fewer families have had ABR specifically geared toward ANSD. While ABR can reveal absent or abnormal waves despite intact outer hair cells, research shows it may not be as sensitive as we think. This is especially true in milder or variable cases, where results may not be replicable and patterns can be hard to interpret.
Because of these gaps, I have been using hearing aid trials as a practical screening tool. This is not a replacement for ABR, but it can give us quick, functional insight. Studies suggest 10 to 15 percent of milder ANSD cases benefit from amplification. Features like frequency compression in devices such as Phonak or Unitron can help address high-frequency desynchrony, which sometimes overlaps with APD symptoms. If a trial improves clarity and ease of listening, we might be on the right path. If it does not, it is a sign we may need deeper testing.
I would love to hear from you. Have you run into missing reflex or ABR testing for APD or suspected ANSD? Have you tried hearing aids early in the process? Parents and professionals, let’s share ideas and strategies.
