Auditory nerve fibers (ANFs) encode pure tones through two modes of coding, spike time or spike rate, depending on the tone frequency. In response to a low-frequency tone, ANF firing is phase locked to the sinusoidal waveform. Because time coding vanishes with an increase in the tone frequency, high frequency tone coding relies on the spike rate of the ANFs. Adding a continuous broadband noise to a tone compresses the rate-intensity function of ANFs, and shifts its dynamic range towards higher intensities. Thus, the ANFs with elevated threshold/low-spontaneous rate (SR) are thought to contribute to behavioral tone detection in noise. However, this theory relies on the discharge rate of the ANFs. The direct comparison with the masking threshold through spike timing, irrespectively of the spontaneous rate, has not so far been investigated. Taking advantage of a unique proxy to quantify the spike synchrony (i.e. the shuffle autocorrelogram), we show in female gerbils that high-SR ANFs are more adapted to encode low-frequency thresholds through temporal code, giving them a strong robustness in noise. By comparing behavioral thresholds measured using prepulse inhibition of the acoustical startle reflex with population thresholds calculated from ANFs pooled per octave band, we show that threshold based spike timing provides a better estimate of behavioral thresholds in the low-frequency range, whereas the high-frequency behavioral thresholds rely on the spiking rate, particularly in noise. This emphasizes the complementarity of temporal and rate modes to code tone-in-noise thresholds over a large range of frequencies.SIGNIFICANCE STATEMENTThere is a general agreement that high-threshold/low-spontaneous rate (SR) auditory nerve fibers (ANFs) are of the prime importance to operate tone detection in noise. However, this theory is based on the discharge rate of the fibers. Comparing the behavioral thresholds and single ANF thresholds shows this is only true in the high-frequency range of tone stimulations. In the low-frequency range of tones (up to 2.7 kHz in gerbil), the most sensitive ANFs (high-SR fibers) carry neural information through a spike-timing mode, even in noise when tones do not induce a noticeable increment in the spike rate. This emphasizes the interplay between spike-time and spike-rate modes in the auditory nerve to encode tone-in-noise threshold over a large range of tone frequencies.
This research output has an Altmetric Attention Score of 3. This is our high-level measure of the quality and quantity of online attention that it has received. This Attention Score, as well as the ranking and number of research outputs shown below, was calculated when the research output was last mentioned on 31 August 2021.
All research outputs
#21,299,517
of 34,376,207 outputs
Outputs from Journal of Neuroscience
#16,229
of 23,398 outputs
Outputs of similar age
#210,678
of 374,242 outputs
Outputs of similar age from Journal of Neuroscience
#167
of 213 outputs
Altmetric has tracked 34,376,207 research outputs across all sources so far. This one is in the 37th percentile – i.e., 37% of other outputs scored the same or lower than it.
So far Altmetric has tracked 23,398 research outputs from this source. They typically receive a lot more attention than average, with a mean Attention Score of 15.3. This one is in the 30th percentile – i.e., 30% of its peers scored the same or lower than it.
Older research outputs will score higher simply because they've had more time to accumulate mentions. To account for age we can compare this Altmetric Attention Score to the 374,242 tracked outputs that were published within six weeks on either side of this one in any source. This one is in the 43rd percentile – i.e., 43% of its contemporaries scored the same or lower than it.
We're also able to compare this research output to 213 others from the same source and published within six weeks on either side of this one. This one is in the 20th percentile – i.e., 20% of its contemporaries scored the same or lower than it.
