How do we hear?
Many of us are sometimes interested in a simple physiological question about how we hear. Let's look at what our auditory organ consists of and how its work takes place.
First of all, we note that the auditory analyzer has four parts:
- External ear. To it carry an auditory drive, an auricle, and also a tympanic membrane. The latter serves to isolate the inner end of the auditory wire from the environment. As for the ear canal, it has a perfectly curved shape about 2.5 centimeters in length. On the surface of the ear canal there are glands, and also it is covered with hairs. It is these glands that secrete the earwax, which we clean out in the morning. Also, the auditory meatus is necessary to maintain the necessary humidity and temperature inside the ear.
- Middle ear. The component of the auditory analyzer, which is located behind the eardrum and filled with air, is called the middle ear. It is connected by the Eustachian tube with the nasopharynx. The Eustachian tube is a fairly narrow cartilaginous canal, which is normally closed. When we make swallowing movements, it opens and through it enters the cavity air. Inside the middle ear are three small auditory ossicles: an anvil, a hammer and a stirrup. The hammer with one end connects to the stirrup, and it is already with the lining in the inner ear. Under the influence of sounds, the eardrum is in constant motion, and the auditory ossicles already transmit its fluctuations inward. It is one of the most important elements that must be studied when considering which structure of the human ear
- The inner ear. In this part of the auditory ensemble there are several structures at once, but only one of them - the snail - controls the rumor. This name was received because of its spiral shape. It has three channels, which are filled with lymphatic fluids. In the middle channel, the liquid differs considerably in composition from the others. The organ that is responsible for hearing is called the Corti's organ and is located in the middle channel. It consists of several thousand hairs that capture the vibrations that create a fluid moving along the channel. Here, electrical impulses are generated, which are then transmitted to the cerebral cortex. A particular hair cell responds to a particular kind of sound. If it happens that the hair cell dies, then the person ceases to perceive this or that sound. Also, in order to understand how a person hears, auditory conductive paths should also be considered.
They are a set of fibers thatconduct nerve impulses from the snail itself and to the auditory centers of your head. It is thanks to the ways our brain perceives this or that sound. Hearing centers are located in the temporal lobes of the brain. The sound that passes through the outer ear to the brain lasts about ten milliseconds.
How we perceive sound
The human ear processes received fromenvironment sounds in special mechanical vibrations, which then transform the fluid movements in the cochlea into electrical impulses. They follow the pathways of the central auditory system to the temporal parts of the brain, then to be recognized and treated. Now the intermediate nodes and the brain itself extract some information about the loudness and pitch of the sound, as well as other characteristics such as the time of sound capture, the direction of sound, and others. Thus, the brain can perceive the information received from each ear in turn or together, gaining a single sensation.
It is known that inside our ear some"Templates" of already studied sounds that our brain recognized. They help the brain correctly sort and determine the primary source of information. If the sound decreases, the brain accordingly begins to receive incorrect information, which can lead to an incorrect interpretation of sounds. But not only sounds can be distorted, over time the brain also undergoes the wrong interpretation of certain sounds. The result may be an incorrect human response or incorrect interpretation of information. In order to correctly hear and reliably interpret what we heard, we will need synchronous work, both of the brain and of the auditory analyzer. That is why it can be noted that a person hears not only the ears, but also the brain.
Thus, the structure of the human ear is quite complicated. Only the coordinated work of all parts of the organ of hearing and the brain will allow us to correctly understand and interpret what we heard.