To add to what ATA said, attention and consciousness is a top-down process. This means that the brain filters out what does not match with external stimuli using feedback loops that terminate or continue the circuit. This process is regulatory and homeostatic in nature, and thus, when you are presented with a healthy and waking subject, most abnormalities are shrugged off as a mental fart, coincidences, or faults in memory and are generally viewed as insignificant--typically because within a second or two it goes away.
When you deprive your brain of senses, the feedback loops actually decouple with your conscious mind and begin to put out their own stimuli. That is to say, you start to hallucinate, get strange feelings, become confused, get strange intuitive senses, make random connections between seemingly unrelated things, etc. For instance, if you cut off visual input for as little as 15 minutes, your mind begins to devote energy to other senses, but it still manages to "see" things. The longer you deprive your senses, and the more senses you deprive, the more likely you will reach highly altered states of consciousness.
The noises could be your brain interpreting communication with itself, or the lack thereof. It could be taking white noise and amplifying it and the feedback loops are not properly terminating themselves, again leading to some sort of hallucination. Voices and faces are things the brain is constantly trying to recognize and interpret. It only makes sense we hear voices when our brains begin to go a bit haywire and we see faces in clouds or in natural geological formations.
Dissociatives and psychedelics are known to cause feelings of vibrations, hearing voices and music and sounds that are not there, seeing faces in things, flat out odd sensations and the like. On dissociatives in particular I have heard what sounds like grinding gears, running machines, the buzzing of fridges, airplane engines, and noises that were otherwise mechanical in nature. It may be due to small seizures or bursts (or a lack) of activity in the temporal lobes in particular (they deal with sound and your sense of time). The parietal lobe provides an all encompassing picture of all your senses and also your sense of self (where the world begins and you end). The prefrontal cortex is vital in combining your sense of self with your sense of time and your reality as well. The truth is, pinpointing the cause is very difficult, but it's easy to make some educated guesses given you know enough about how the mind functions and why.
|
|
Bookmarks