Functional classification of neurons

Functional classification of neurons divides them by the nature of the functions performed by them (according to their place in the reflex arc) into three types: the afferent (sensory), efferent (and mot-inflammatory) and associative.

1. Afferent neurons (synonyms – sensitive, receptor, centripetal), as a rule, are lozhnounipolyarnymi ner in-GOVERNMENTAL cells. The bodies of these neurons are located not in the central nervous system, and in the back of thebrain and cranial nerves of sensitive sites. One of the appendages extending from a nerve cell body, to be on the periphery, to the fire and other body end there touch receptor cat ing able to transform the energy of the external stimulus (irritation) into nerve impulses. The second process goes to the central nervous system (spinal cord) as part of the posterior roots of the spinal nerves or the corresponding sensory fibers of the cranial nerves. Typically, AFF e rental neurons are small and well branched at the periphery of a dendrite. The functions of afferent neurons are closely related to the functions of sensory receptors. Thus, afferent neurons generate nerve impulses under the influence of changes in the external or internal environment.

Part of neurons involved in processing sensory information r mation, which can be regarded as a higher afferent neurons of the brain, can be divided depending on the sensitivity and dis t Vija stimuli on monosensornye, bisensornye and polytouch.

Monosensory neurons often located in the primary projection n GOVERNMENTAL cortical areas and respond only to their signals sensorially. Mon – sensory neurons are divided functionally by their sensitivity to different qualities of a single stimulus into monomodal, bimodal and polymodal.

Bensor neurons more often they are located in the secondary areas of the cortex of any analyzer and can react to signals of both their own and other sensory characteristics. For example, neurons in the secondary visual areas of the bdomain of the cerebral cortex of the brain react to visual and auditory stimuli. Polysensory neurons – this is most often the neural of the associative brain zones, they are able to respond to the stimulation of different sensory systems.

2. Efferent neurons (motor, motor, secretory, centrifugal, cardiac, vasomotor and   etc.) are designed to transmit information from the central nervous system to the periphery, to the working bodies. P on its structure efferent neurons – a multipolar neurons, the axons of which continues in the form of somatic and autonomic nerve fibers (peripheral nerves) to the relevant working bodies, including skeletal and smooth muscle, as well as to many of thenumerical glands. The main feature of efferent neurons is the presence of a long axon, which has a high rate of excitation.

3 Inserted neurons (interneurons associative transmit a nerve impulse afferent (sensitive) neuron to efferent (motor) neurons. internuncial neurons located within the gray CNS agents. In structure is multipole p nye neurons. It is believed that functionally the most important CNS neurons , since they account for 97   %, And nekot eye on the data – even 99.98   % of the total number of neurons of the central nervous system. The area of ​​influence of intercalary neurons is determined by their structure, including the length of the axon and the number of collateral. According to their function, they can be exciting or inhibitory. Wherein m excitatory neurons of gut not only to transfer information from one neuron to another, but also to modify the transfer of excitation, in particular, to enhance its effec ciency.

local_offerevent_note April 2, 2019

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