The CAL symposium aimed at defining a roadmap and assemble a consortium to influence future funding for research the area of hearing impairment remediation (cochlear implants and hearing aids). It was loosely organized around the theme of the “efferent system”, the centrifugal neural pathway by which the brain controls the peripheral sensory organs and low-level brainstem processing.  The efferent system was the focus of some talks, and for others a metaphor for control of external devices (as in COCOHA).

A few highlights: Barb Shinn-Cunningham emphasized the extreme inter-person variability in the ability to isolate a target from interfering streams based on spatial cues, and the likely role of the loss of low-spontaneous rate nerve fibers in hidden hearing loss. David Ryugo commented on the fact that all efferents are excitatory, and that they become less precise with impairment. Enrique Lopez-Poveda showed that the beneficial effects of intact MOC efferents could be mimicked in cochlear implant patients, by using the input at each ear to down-regulate the input at the other ear, an excellent example about how scientific knowledge can be exploited to immediate benefit.  Thomas Stieglitz gave an overview of the cutting edge in electrode and interface technologies, and  Preben Kidmose focused on one approach of particular interest to COCOHA, that of within-ear dry electrodes. See the CAL2015 website for more!