|
It appears only natural to assume that as our ears pick up sound waves, they convert them into electrical nerve signals that represent the sounds, a loud sound producing a large nerve signal, silence producing no nerve signal at all, and once these nerve signals arrive at the brain we hear them as sounds.
However, our auditory system is not that simple. The electrical signals that travel from the ear to the brain are not an electrical representation of audio waves. The signals passing to the brain when there are no sounds are as strong as the signals produced by loud sounds.
Before the electrical signals from the ears are passed to that portion of the brain that hears the sounds, they pass through neural networks that act as filters. These filters are part of the subconscious part of the brain, and are closely connected with the part of the brain that controls emotions and the automatic response of the body to danger.
Experience continuously alters these neural networks, changing which signals are enhanced, which are attenuated, and which totally suppressed, before the signals are presented to the cerebral cortex to be perceived a sounds. Essentially, these neural networks try to pass sounds on a "need to hear" basis.
Think of how we detect the sound of our own name, a distant car horn, or a new baby stirring in its sleep, whereas we may be unaware of the sound of the blood rushing through our arteries, rain pounding on the roof, or traffic noises from a nearby street.
Signals that are new, or associated with a negative experiences, are enhanced to alert the body to prepare for "fight or flight." Interesting enough, signals that are recognised as representing a known danger evoke a weaker reaction of the autonomic system than those categorised as an unknown danger. Signals that are recognized as having occurred before, and which not being associated with positive or negative events, evoke the lea...
|
Windows Software
Albina Merfyn - I find this to be really easy to use. I can...
