How does the brain know from which part of the body sensory information comes?

Question

For instance, how does it know that a specific nerve termination comes from my left foot and not from the tip of my nose?

Amy K: yes but after all what does this explain? Why do nerves in different parts of the body going to different parts of the brain let emerge a spatial representation of our body? These different parts could equally well produce, say, different sounds, or different smells. There must be something more in our brain which brings these different areas together, not into a mix of sounds and tastes or smells, but into a spatial concept/sensation.

Anshika g: transforming a signal does not tell us where it comes from. The brain sees only the end of that fiber nerve. How does it know that it comes just from that specific part of the body? Moreover, why does it not transform these signals in sounds or tastes, instead of a spatial representation?

Perhaps I should reformulate the question better, i.e.: "How does the brain build the notion of 'space' ?" It seems a more philosophical question (it is partially indeed), but I'm actually interested in the strictly neurological aspect of "spatial reconstruction". Lani S says that the brain "has a special power to determine the source of every nerve involved". Ok, ... but HOW does it know that? For instance, if it receives signals from fiber X and fiber Y corresponding to receptor X and receptor Y, how does it know that those two fibers correspond to two receptors few mm apart from each others and not, say 30 cm apart? The signals alone can't be the end of the story. The brain MUST also know how the receptors are distributed on our body. Otherwise it won't be able to reconstruct any 3D image. In what way does it know that? Does someone have any idea if neuroscience sheds some light on this?

Answer 1

It sounds like you are trying to figure out something beyond the capacity of human understanding.

Anyway, the functions of the brain are both mysterious and remarkable. The brain has a superpower to review and identify all stimuli,all the sensations, and all the informations received from nerves connecting to the different parts of the body all at once.

The brain stem functions as the communications trunk between the brain and the rest of the body.On the other hand, each body organs and senses have their own specific location of direct connection on the brain. Each small area on the body has its own touch sensor and has specific pathway of connecting into the brain. All of those sensing elements can enter the brain at the same time on their designated spots of connection.No time sharing or switching.

The brain as an organ of many thousands of interlocking functions, and as a cooperative of hundreds,(or thousands) of "mini-brains" in return is so much in tune that it appears and functions as one. It also has thousands of individual reactive decision mechanisms, each with its own memory, interconnection with all others, and judgement capability of accurate determination of multiple sensory informations. So, in normal conditions the brain has a special power to determine the source of every nerve involved.

You see, no one has yet succeeded a full understanding of the human brain .AND, no computer has yet come close to matching its capabilities.

Well, that is the capability of my brain to understand THE BRAIN for now.

Answer 2

Because nerves in different parts of the body go to different parts of the brain. Its like a mega computer.

Answer 3

because we have sensory nerves in all parts of the body sending signals to the nervous system..and in there it transforms the signals in telling you where it came from.

Answer 4

http://www.ninds.nih.gov/disorders/brain_basics/know_your_brain.htm