Internal decision noise rises as speech-to-noise ratio falls.

Evidence

It was shown that the internal noise increased with decreasing SNR. This could be incorporated in the model using an SNR-dependent random process in the decision stage (instead of SNR-dependent templates). … It remains a challenge to include listener-specific differences in the model, as it is not clear whether these differences can be accounted for by slight sensitivity differences between the NH listeners, cognitive effects, individual biases, or any combination of these factors. — Dijk, Pim van, Physiology, Psychoacoustics and…, 5621

The perceptual data analysis has implications for the further model design. It was shown that the internal noise increased with decreasing SNR. This could be incorporated in the model using an SNR-dependent random process in the decision stage (instead of SNR-dependent templates). Furthermore, the model predicted responses of a hypothetical “average” NH listener, which is unrealistic given the considerable across-listener variability. — Dijk, Pim van, Physiology, Psychoacoustics and…, 5621

The perceptual data analysis has implications for the further model design. It was shown that the internal noise increased with decreasing SNR. This could be incorporated in the model using an SNR-dependent random process in the decision stage (instead of SNR-dependent templates). Furthermore, the model predicted responses of a hypothetical “average” NH listener, which is unrealistic given the considerable across-listener variability. It remains a challenge to include listener-specific differences in the model, as it is not clear whether these differences can be accounted for by slight sensitivity differences between the NH listeners, cognitive effects, individual biases, or any combination of these factors. — Dijk, Pim van, Physiology, Psychoacoustics and…, 5624

Categorization

• QUESTION: What physiological mechanism makes internal noise SNR-dependent - is it spontaneous-rate nerve firings, adaptation, or decision-stage uncertainty?
• corroborated: 3 independent passages support this claim — Dijk, Pim van, Physiology, Psychoacoustics and…, 5621; Dijk, Pim van, Physiology, Psychoacoustics and…, 5624