SPECTROTEMPORAL RECEPTIVE-FIELDS OF NEURONS IN COCHLEAR NUCLEUS OF GUINEA-PIG

Spectrotemporal receptive fields (STRFs) [Hermes et al., Hear. Res. 5, 147-178, 1981] for neurons in the cochlear nuclei (CN) of guinea pig were estimated. Sixteen periodic segments of bandlimited, synthesized noise evoked replicable, distinctive period histograms for spike discharges. All driven units in the major divisions of the CN having their characteristic frequency (CF) within the noise bandlimits had unique STRFs for a given intensity of noise stimulation. The STRF maximum corresponded to the unit's CF, and details of the STRF patterns differed over CN divisions and response classes derived from tonebursts. The sizes of features in STRFs from this mammal appeared significantly smaller in their temporal and spectral extents than those reported in the torus semicircularis of an amphibian and were roughly comparable to the few units reported from cat ventral CN [Eggermont et al., Quart. Rev. Biophys. 16, 341-414, 1983]. STRFs, as they are presently obtained, provide useful insight into some aspects of afferent processing and perhaps connectivity, but their interpretation is specific to the level of stimulation and limited by the need to choose a specific energy distribution to represent the stimulus.