Only masker power within the critical band around a signal affects its threshold

Evidence

A filter, centered at the signal frequency, only passes certain frequencies that are defined by the critical band. Any frequency outside of the critical band surrounding the signal cannot mask that signal. This is why thresholds did not change as the masker bandwidth was widened beyond the critical band. — Jennifer Lentz, Psychoacoustics- Perception of Normal…, 476

Categorization

• DEFINE: Explains the mechanism by which frequency selectivity limits which maskers affect a signal.