ABSTRACT
We review the properties of rate-place representations of single tone frequency and intensity in backgrounds of quiet and broadband noise. Special emphasis is placed on statistical analysis of auditory-nerve rate responses, the role of low spontaneous rate fibers, and effects of efferent stimulation. Rate-place profiles encode tone frequency and intensity over a wide range of tone and noise levels if the properties of low spontaneous rate fibers are taken into account. Efferent input to the cochlea may improve rate-place representations in noise backgrounds. The experimental data show that selective weighting of the responses of low versus high threshold fibers is crucial if rate-place representations are to remain robust over a wide range of stimulus levels. We suggest a simple neural circuit that may be capable of performing this weighting.
