What field of study focuses on how a person's experience changes with the intensity of a sound?

The field of study that focuses on how a person's experience changes with the intensity of a sound is psychophysics. This discipline is concerned with understanding the relationship between physical stimuli and the sensations and perceptions they produce. Specifically, it examines how variations in stimulus intensity can influence sensory experience and perceptual processes.

For example, psychophysical research might involve measuring how a person perceives differences in loudness as sound intensity increases, applying methods like the just noticeable difference (JND) to determine thresholds of perception. This demonstrates how our sensory systems relate to objective measures of the physical world, such as sound intensity.

In contrast, sensation refers more broadly to the process of detecting physical energy from the environment through our sensory receptors, while perception involves interpreting and organizing that sensory information. Biophysics, on the other hand, deals with the application of the principles of physics to biological systems, which does not specifically address the subjective experience of sound intensity.