O think the ears
Indirectly, yes. The skin passes feelings of soft, hard, cold, or hot to the brain. The eyes send images. The nose sends smells, and the mouth sends flavors. The ears send sounds and balance. These are all processed in the brain.
your nervous system sends messages to your brain
I'm guessing the ear, since it mostly deals with sounds/sound waves and sends them to your brain...
Your brain sends singles to your body and your heart sends blood through your body
There are several (a lot) of tiny hair like structures inside the ear will vibrate in response to certain sound frequencies. When a hair vibrates, it stimulates a particular cell which sends a signal to the neurons next to it, to the brain. The brain takes all of the inputs and can interpret that as sounds and frequencies. Louder sounds will cause it to vibrate more, so the brain can interpret that as well.
The retina detects light and the optical nerve sends the signal to the brain.
Brain sends signal through spinal cord to nerves. Nerves contract which muscle to move and sends a message back to the brain. BOOM! Movement.
Crude sounds are formed into speech through a complex process involving the brain, vocal cords, lungs, mouth, and throat. The brain sends signals to the vocal cords to vibrate and produce sound, which is then shaped by the mouth and throat into specific sounds and words. This process allows us to create and communicate in a wide variety of languages and dialects.
Sound waves enter the ear and cause vibrations in the eardrum, which are transmitted to the inner ear through the ossicles (tiny bones). In the cochlea, these vibrations are converted into electrical impulses by hair cells. These impulses travel along the auditory nerve to the brain, where they are processed and interpreted as sounds.
The vibration from sounds hit the tympanic membrane (ear drum), which in turns causes the ossicles (malleus, incus, and stapes) to amplify and send the signals to the cochlear (inner ear). The cochlear processes the sounds and sends the information through the Vestibulocochlear nerve to the brain.
The brain.
Retina