But another very well-known technical phenomenon regarding the impact of the receiver of a transmission has found little awareness or discussion. Lets look at the following transmission graph:
|Transmission Signal vs. Background Noise Floor|
In fact, the background noise doesn't just disappear. However, it is removed from the signal by processes which are only activated when the receiver of the signal is alerted and begins differentiating between noise and signal, effectively removing noise that would otherwise interfere or negatively impact the reception.
This is a very real effect, and is hard-wired into human perception. It is linked to attention-span and attention-focus, and activates powerful information filters already designed into our input receptors. If it were not for this advanced and largely uncontrolled, automatic function, we would be overwhelmed with non-essential and distracting information from all our senses. But human beings are designed to automatically filter out distractions (background noise), detect and selectively concentrate on the signal of interest, in part chosen by the listener.
While mechanical and electronic filters are usually very primitive and crude, simply shutting down or stopping the flow of frequency ranges or patterns known to be "noise-full" or "noise-like" (i.e., carrying noise), the human brain and itsprocesses are quite sophisticated and can be trained via pattern-matching and reasoning processes to intelligently and very effectively mask out unwanted noise from the signal.
As a result, humans are able to perform nearly 'super-human' feats of concentration, memory, and filtering that ordinary electronic devices are incapable of. The analogy can be likened to imagining the difference between a person with good eyesight and lighting, versus a blind person, in attempting to do the dishes, or drive a car. Even in such a simple and usually easy task, the trained eye is a powerful and essential tool, changing what is nearly impossible (for the blind person) into a virtually error-free operation.
The key component here is not the "background noise level" facing the transmitter of the message, but the amazingly gifted ability of the receiver, who can have quite fantastic powers to filter out noise and errors in the process of transmission. These powers are based on extremely intelligent and sophisticated processes possessed by the receiver, and enable very crude and primitive transmissions to be very successful with a high accuracy, frequency and duration.
- Joe Layman