Noise Pollution Effects on Human Behaviors
While noise pollution is not pollution in the traditional sense of the word, it can have similar negative effects on people and the world. Noise pollution is created by displeasing noises from any source: human, animal, or machine. These noises fill specific areas with sound, and cause many health and behavioral effects. Noise pollution does not produce the same kind of physical substance as industrial or environmental pollution, but is just as prevalent around the globe, and can be just as damaging in ways.
The effects of noise pollution, as well as the causes, are paramount across the world. Damaging to mental health, noise can produce annoyance and irritation, and this can quickly lead to aggression. This cycle of noise can soon lead to violence, hypertension, stress, sleep loss, hearing loss, and other unnoticed effects. The high blood pressure produced by stress from noise pollution can lead to cardiovascular effects, bad tempers, and even harmful reactions like heart attacks in the most extreme.
Stress
Noise Stress and Brain Function-Study
Stress can exacerbate a number of psychiatric disorders, many of which are associated with the prefrontal cortex (PFC), the area of the brain unique to humans. A Yale University study looked at the effects of noise stress on brain function in monkeys. Results indicate that stress impairs PFC cognitive function through its influence on dopamine, a key neurotransmitter that's involved in many brain disorders, including ADHD and Parkinson's disease.
Responding to Noise We Cannot Hear-Study
Even sounds you can't hear can have a powerful affect on your nervous system. One example is the "infrasound" in the roar of a tiger.
A tiger's intimidating roar has the power to paralyze animals. 
Even experienced human trainers are stunned. "We suspect that this is caused by the low frequencies and loudness of the sound," says Elizabeth von Muggenthaler, a bioacoustician from the Fauna Communications Research Institute in North Carolina. "Humans can hear frequencies from 20 hertz to 20,000 hertz, but whales, elephants, rhinos, and tigers can produce sounds below 20 hertz."
The shocking power of a tiger's roar is one example of how humans react to a sound they cannot detect with their ears. But what about all the noise generated by our modern world – including the multitude of ultrasounds whose frequencies are above 20,000 hertz and beyond our hearing range?
Low-Level Noise and Stress-Research
Not just loud or sudden noises provoke a stress response. Chronic low-level noise also negatively influences the brain and behavior. Whether from the road or in the office, low-intensity noise has a subtle yet insidious effect on our health and well-being.
Noise at home or school can affect children's ability to learn. Compared to kids from quieter neighborhoods, children living near airports or busy highways tend to have lower reading scores and develop language skills more slowly. Psychiatric hospitalizations are higher in noisy communities. Bad moods, lack of concentration, fatigue, and poor work performance can result from continual exposure to unpleasant noise
Traffic Noise Increases Stress Hormones in Children-Study
Even everyday traffic noise can harm the health and well-being of children. In the first study to look at the non-auditory health effects of typical ambient community noise, it was shown that chronic low-level noise from local traffic raised levels of stress hormones in children, as well as their blood pressure and heart rates.
"We found that even low-level noise can be a stressor. It elevates psychophysiological factors and triggers more symptoms of anxiety and nervousness," says environmental psychologist Gary Evans of Cornell University, an international expert on environmental stress, such as noise, crowding, and air pollution.
The children in noisier neighborhoods experienced higher overnight levels of the stress hormone cortisol, marginally higher resting systolic blood pressure, and greater heart rate reactivity to a stress test – all signs of modestly elevated physiological stress.
Background noise had a significant effect on stress levels, said Lercher. Therefore, chronic exposure to nearby sounds from roads and train lines are a concern.
Females at Higher Risk from Noise Stress
Girls exposed to the traffic noise become less motivated, presumably from the sense of helplessness that can develop from noise they couldn't control.
Women respond differently to loud noise, too. A study at Texas A&M University found that "women have a lower threshold to experience noise as stressful," according to psychologist Dr. Mary W. Meagher. "Our data suggest that women may be more sensitive to noise stress than men."
Office Noise-Study
Forty experienced female clerical workers (average age 37) were assigned for three hours to either a quiet office or one with low-intensity office noise (including speech). The workers in the noisy office experienced significantly higher levels of stress
Annoyance
When young children are exposed to speech interference levels of noise on a regular basis (the actual volume of which varies depending on distance and loudness of the speaker), they may develop speech or reading difficulties, because auditory processing functions are compromised. Children continue to develop their speech perception abilities until they reach their teenage years. Evidence has shown that when children learn in noisier classrooms, they have a more difficult time understanding speech than those who learn in quieter settings. In a study conducted by Cornell University in 1993, children exposed to noise in learning environments experienced trouble with word discrimination as well as various cognitive developmental delays. In particular the writing learning impairment known as dysgraphia is commonly associated with environmental stressors in the classroom. The effect of high noise levels on small children has been known to cause physical health damages as well. Children from noisy residences often possess a heart rate that is significantly higher (by 2 beats/min on average) than in children from quieter residences.
Furthermore, studies have shown that neighborhood noise (consisting of noise from neighboring apartments, as well as noise within one's own apartment or home) can cause significant irritation and noise stress within people, due to the great deal of time people spend within their residences. This can result in an increased risk of depression and psychological disorders, migraines, and even emotional stress.
In the workplace, noise pollution is generally a problem once the noise level is greater than 55 dB(A). Selected studies show that approximately 35 to 40% of workers in office settings find noise levels from 55 to 60 dB(A) to be extremely irritating. In fact, the noise standard in Germany for mentally stressful tasks is set at 55 dB(A). However, if the noise is source is continuous, the threshold level for tolerable noise levels amongst office workers actually becomes lower than 55 dB(A).
One important effect of noise is to make a person's speech less easy to hear. The human brain automatically compensates the production of speech for background noise in a process called the Lombard effect in which it becomes louder with more distinct syllables. But this cannot fully remove the problems of communication intelligibility made in noise.