An overview on informational masking

Abstract

Background and Aim: In noisy environments, two types of masking including energetic mask­ing (EM) and informational masking (IM) occur. EM results from the spectral overlap of the target and maskers on the basilar membrane, while IM occurs at higher level. This paper aimed to rev­iew the concept of IM in terms of historical perspective and definitions, the important cues for releasing from it, age-related effects and its neural basis.

Recent Findings: The data from psychoacoustic, behavioral, and neuro-imaging studies were revi­ewed and discussed in order to provide an overall image of IM. According to these studies, it seems that perceptual segregation between the target and maskers is the most important cues for relea­sing from IM. This process takes place simply and without any effort in adults with normal hearing; however, it does not occur easily in chil­dren, elderly people and those with impaired hearing. Moreover, it seems that both top-down and bottom-up processing are involved in IM for­mation.

Conclusion: Since IM leads to failure in selec­tion of auditory objects and prevents the indivi­dual from auditory scene analysis, understanding the IM concept leads to a better knowledge of speech perception in noise.

Keywords: Informational masking; perceptual masking; energetic masking