Final answer:
Central masking typically represents a 5 dB HL shift in threshold, which is significant in audiometric testing. For a 50-dB hearing loss, sound needs to be amplified by a factor of 100,000 times the threshold of hearing for normal perception, while ensuring that amplification does not further damage hearing.
Step-by-step explanation:
The question pertains to the concept of central masking in audiology, which is related to changes in hearing thresholds when noise is introduced to the non-test ear. Clinicians generally consider the magnitude of central masking to be approximately a 5 dB HL (decibel Hearing Level) shift. This concept is crucial in audiometric testing and in understanding the relationship between signal and noise in the auditory process.
For the given scenario of a person with a 50-dB hearing loss at all frequencies, low-intensity sounds would need to be amplified by factors of 10 for the sounds to seem normal. The decibel scale is logarithmic, and as per the provided information, every increase by 10 dB corresponds to a sound that is 10 times more intense. Therefore, a 50-dB hearing loss indicates that sounds need to be amplified 10^5 (or 100,000 times) the threshold of hearing to seem normal.
Considering the importance of avoiding further hearing damage, amplification for more intense sounds should be smaller than for low-intensity sounds, as recommended by several health-related professional associations that suggest keeping sound exposure below 85 dB for 8-hour daily exposures without hearing protection.