Answer to Question 1
The two main types of VIII nerve neurons are:
High-threshold neurons require a higher intensity and encompass the higher end of our auditory system of signal intensity. Thus high-threshold fibers may process higher levels of sound.
Low-threshold neurons may process near-threshold sounds. Low threshold fibers respond at very low signal levels and display random firing even when no stimulus is present.
Answer to Question 2
Loud noise or noise pollution can result in high blood pressure (hypertension), which is a major cause of strokes in humans. In 2008, researchers studied how nighttime noise affected people who lived near airports in Europe. The authors learned that every 10 dB increase in noise during the night increased the possibility for people to later develop high blood pressure by 14. Researchers also discovered that not only can airplane noise have this effect, but so can sleeping with a partner who snores loudly. Thus a quiet environment helps prevent hypertension and possibly stroke.
