Is one man’s noise another man’s music?
Noise is considered a type of pollution because it is an unwanted stimulus that intrudes into a person’s environment, but it is quite difficult to define in any objective way. Definitions are invariably subjective because noise is a sound that a person does not want to hear (Evans & Stecker, 2004).
Some research suggests that the subjective experience of noise (i.e., annoyance), not the level of noise itself, is the important factor regarding people’s health (Nivision & Endresen, 1993). Much research has examined chronic noise exposure (defined objectively as a critical level of decibel) in relatively large samples. However, the effects of noise are also influenced by other factors such as personality and meaningfulness of the noise (Cohen et al., 1986). Babisch and colleagues (2013) emphasize that noise annoyance is largely determined by noise level, so both factors are not independent of one another.
Do we “get used to” noise?
Subjective reports reveal that people begin to sleep better as they get used to traffic noise, which reflects a so-called habituation process. However, objective polygraphic examinations of people’s brains do not reveal any changes as people begin to “get used to” noise (Kuroiwa et al., 2002; Xin et al., 2000).
In fact, noise exposure may sometimes lead to increased sensitization to noise (Nivison & Endresen, 1993). It seems that some individuals habituate to noise, while others do not. How people adapt seems to depend on people’s sensitivity or personality (Kawada, 2011).
Predictability and the possibility of controlling unwanted noise has been found to reduce cognitive after-effects of noise exposure (Glass & Singer, 1972). Indeed, stress experiments have demonstrated that control is an important factor in moderating one’s physiological stress reactions (Babisch, 2001).
Noise affects us via two distinct routes
The noise reaction model proposes that noise activates the human organism via a direct and an indirect route. The direct route is determined by the immediate interaction of the acoustic nerve with different structures of the central nervous system, which in turn increases physiological stress. The indirect route refers to the cognitive perception of noise, and it is linked to an increase in emotional stress. Both routes activate the autonomic nervous system and the endocrine system, and a long-term overactivation of these systems may have adverse health effects (Babisch et al., 2013).
Many of us live in noisy environments and seem to do fine, but how does noise exposure in fact affect us physically as well as psychologically. What does research tell us? In this article, I present six unfortunate ways that noise affects us.
1. Cognitive functioning
Stansfeld and colleagues (2005) examined how aircraft and road traffic noise influenced almost 3,000 children’s cognition and health. The study was cross-national with participants from both the Netherlands, Spain and UK.
The authors found a linear exposure-effect association between chronic exposure to aircraft noise at school (not traffic noise) and impaired reading comprehension and recognition memory in children. Neither aircraft noise nor traffic noise affected sustained attention. In this study, traffic noise did not have a negative impact on children’s cogniton. The authors provide a possible explanation:
… sound that shows appreciable variation over time (changing state) impairs cognitive function whereas sound that does not vary (steady state) has little effect. The noise of aircraft flyovers has an unpredictable rise time that might attract attention and distract children from learning tasks. (p. 1948).
One study found that reading scores of children in classrooms near train tracks were lower than scores of children whose classrooms were quieter (Bronzaft & McCarthy, 1975). Another study found that noise affected long-term memory in 9-12 year-old children (Evans et al., 1995).
Yet another study by Tassi and colleagues (2013), involving 20 individuals exposed to daily railway noise and 20 individuals living in quiet environments, found that long term exposure to railway noise had some unfortunate consequences, reflected by increased reaction times in different cognitive tasks and declines of some parts of the attentional system.
Read More: Here
Related: The Undistorted Power of Attention