“…The consistency of the singers’ loss of SPL in the NM condition may lie not in vocal or auditory malfunction but in other sensory feedback. Reflexive responses to auditory feedback in relation to the regulation of intensity of vocal SPL have been documented (Chang-yit, 1975; Fulton & Spuehler, 1962): the Lombard effect (Lane & Tranel, 1971; Winkworth & Davis, 1997), whereby speakers raise their sound level with increases in background noise; and the sidetone effect, whereby speakers lower their vocal level if the auditory feedback of their own voice is artificially increased (Fulton & Spuehler, 1962; Lane, Catania, & Stevens, 1961). There is also evidence that an automatic mechanism for regulating voice SPL exists but that it is only accurate for changes up to 1dB (Bauer, Mittal, Larson, & Hain, 2006).…”