No single auditory nerve fiber spans the full dynamic range of human hearing.

Evidence

Due to the saturation and limited dynamic ranges of individual fibers, an individual neuron cannot code the entire range of sound levels that are perceived by the human ear. The dynamic range (the range of levels between threshold and saturation) of an individual neuron is on the order of 20 to 40 dB and rarely exceeds 60 dB. Note that the dynamic range of human hearing is considered to be approximately 100 to 120 dB, suggesting that all three fiber types must be used to represent the entire dynamic range of hearing. Consider then that the high SR/low threshold fibers would be most involved in representing lowlevel stimuli, such as when auditory threshold is measured. On the other hand, high threshold/low SR fibers are most involved in auditory detection when a background noise is present. — Jennifer Lentz, Psychoacoustics- Perception of Normal…, 240

Categorization

Category: Causal Relationships

• DEFINE: Defines dynamic range as the range between threshold and saturation, contrasting neural (20-60 dB) with perceptual (100-120 dB).
• XREF: Explains the physiological basis of loudness recruitment in hearing loss and why quiet vs. noisy listening conditions recruit different fiber populations.
• SEED: An accessible essay angle: how the ear’s three fiber ‘teams’ handle loud and quiet listening, and what this means for how hearing loss changes everyday perception.

Related

• Individual auditory nerve fibers cannot code the full hearing dynamic range (similarity 0.92)
• The auditory system’s ~120 dB dynamic range exceeds any single nerve fiber’s coding capacity (similarity 0.91)
• Single auditory nerve fibres encode only a narrow 20-40 dB dynamic range. (similarity 0.88)
• Single auditory neurons encode only a narrow 20-40 dB dynamic range (similarity 0.88)
• Auditory nerve fibers of three spontaneous-rate types code different level ranges (similarity 0.88)
• Individual auditory fibres cover only 40-60 dB yet we hear over 100 dB range (similarity 0.86)
• Loudness coding requires pooled responses across many auditory nerve fibers (similarity 0.85)
• Different auditory nerve fiber types have distinct response thresholds. (similarity 0.84)
• Fiber-type-specific damage produces distinct loudness perception abnormalities. (similarity 0.83)
• High-frequency auditory nerve fibers receive far more broadband noise power than low-frequency fibers. (similarity 0.83)
• Hearing loss squeezes the full loudness range into a much smaller dynamic range (similarity 0.83)
• Auditory nerve fibers divide into three types by spontaneous firing rate. (similarity 0.83)
• A single auditory nerve fibre’s firing is unpredictable and noisy (similarity 0.83)
• Damage to high-threshold auditory nerve fibers can escape threshold detection yet impair speech-in-noise perception. (similarity 0.82)
• Auditory nerve fibers’ thresholds correlate inversely with their spontaneous firing rates. (similarity 0.82)