I'm in Washington DC for the annual meeting of the Society for Neuroscience (SfN). SfN was my first scientific conference (San Diego, 2001) and it always has a special place in my heart: I'm always inspired by the diversity of methods and approaches to studying the brain.
This year I had the pleasure of speaking in a symposium on hearing impairment that Art Wingfield and I organized. Andy King started the symposium off by talking about animal models of hearing loss, and how hearing impairment affects spatial localization abilities. Barb Shinn-Cunningham talked about the impact of hearing loss on auditory attention in human listeners. Paul Miller talked about some elegant cognitive modeling work he has done to tease apart cognitive processes involved in processing degraded speech. And I finished up the session by attempting to summarize the rather large literature on the cognitive effects of acoustic challenge.
One analogy to hearing impairment is to think about having blurred vision. Those of us who wear glasses can attest to the fact that it's possible to see things without them, but it can be more difficult (and we may make more errors!). The analogy to vision is imperfect, however, because we frequently have the opportunity to look at objects around us for as long as we'd like to. When listening to degraded speech, we have only a brief moment to understand what we hear. If we are unable to, we need to maintain a representation in memory to have any hope of recovering meaning.
The simple take home message is that hearing loss impacts neural functioning at multiple levels, from "low level" responses in auditory cortex to affecting verbal short-term memory and attention-based performance monitoring in humans. Although the details are still actively being investigated it was inspiring to see, again, the multidisciplinary approaches being taken.