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Reflex is the response of the body to irritation emanating from the external or internal environment with the participation of the nervous system.
Each reflex is carried out using a reflex arc
The reflex arc of the spinal reflex consists, as a rule, of two to three neurons.
Each reflex arc consists of an afferent (sensitive) link beginning with a receptor apparatus and an efferent (motor) link ending with a working organ (effector) Quite often, between two indicated links there are one or two insertion neurons that receive pulses from receptor apparatuses and process them into centrifugal ones impulses going to the executive body.
In the autonomic nervous system, reflex effects can also occur in the presence of only one neuron. This refers to the axon-reflex, carried out without the participation of the central nervous system and representing the excitation of one axon branch with proximal distribution to the branching point and then again distally along its other branch (.
Distinguish between simple and complex, acquired and innate, unconditioned and conditioned reflexes.
Unconditioned reflexes are congenital, hereditarily fixed reflexes developed in the process of phylogenesis, conditioned ones are inconstant, individual reflexes acquired in ontogenesis as a result of the interaction of the organism with the environment, developed on the basis of unconditioned reflexes. In addition to simple unconditioned reflexes, there are such complex unconditioned reflexes as instincts (food, defensive, sexual, parental).
Conditioned reflexes were discovered by I.M.Sechenov; later they were deeply studied by I.P. Pavlov and his school. The study of conditioned reflexes has opened up broad prospects in understanding the functions of the large brain and its most perfect part - the cortex.
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- Reflex arc, arc links
Reflex arc - a set of sensory and motor structures of the nervous system necessary for the implementation of the reflex. Reflex arc consists of:? receptor - a nerve link that perceives irritation? afferent link - centripetal nerve fiber - processes of receptor neurons that transmit impulses from sensitive nerve endings to the central
- Acoustic Reflex Arc
The afferent (sensory) branch of the arc is the auditory nerve, ending in the ventral cochlear nucleus associated with the superior olivary complex (FOC) of both sides through the trapezius. These two-way connections cause a reflex response from both ears, even if only one ear is stimulated. The efferent (motor) path of the arc extends from the medial accessory core of the wok to
- CONCEPT OF REFLEX AND REFLECTOR ARC
Reflex is the response of the body to irritation emanating from the external or internal environment with the participation of the nervous system. The term “reflex” (from Latin reflexus - to bend backward, involuntary, reflected) was introduced by Descartes, who, transferring the conclusions of his dioptric work to the brain, suggested that animal “spirits” reaching the cavities of the ventricles, like rays of light, are reflected on
- RESEARCH OF REFLECTOR MOTOR FUNCTIONS
In the study of motor functions, first of all, the volume and strength of movements, the state of the muscular system, the presence of muscle weight loss or their excessive development, excessive movements, or, on the contrary, stiffness are determined. Muscle strength is determined by means of special techniques, as well as using dynamometers. It should be borne in mind that the volume and strength of movements may be limited due to diseases
- REFLECTIVE PRINCIPLE OF ACTIVITY OF THE NERVOUS SYSTEM
The essence of the nervous system is to organize reactions in response to external and internal influences. The degree of complexity of such reactions varies widely - from automatic narrowing of the pupil in bright light to a multifaceted behavioral act that mobilizes all body systems. Nevertheless, in all cases, one and the same principle of activity is preserved - reflex. Reflex is
- RESEARCH OF REFLECTOR MOTOR FUNCTIONS
In the study of motor functions, first of all, the volume and strength of movements, the state of the muscular system, the presence of muscle weight loss or their excessive development, excessive movements or, on the contrary, stiffness are determined. Muscle strength is determined using special techniques, as well as using dynamometers (Fig. 37) and evaluated by a five-point system. Preserving motor function of muscle strength
- Crib. Neurology, 2011
Reflex arc. Hematoma. Polyneuritis. Coming disturbances of cerebral circulation. Damage in syphilis. Primary muscular dystrophy. Spinal cord tumors. Brain tumors. Cerebellum. Acute disseminated encephalomyelitis. Manganese, carbon monoxide. Ethyl alcohol. Arsenic: Mercury and lead poisoning. Bulbar, pseudobulbar syndrome. Alternating systems. Myotonic
- UNCONDITIONAL REFLEXES
The reflex arcs of unconditioned reflexes are closed within the spinal cord, brain stem and subcortical nuclei of the brain. The most frequently investigated in the clinic, having topical diagnostic value, unconditioned reflexes are divided into superficial, exteroceptive (skin, reflexes from the mucous membranes) and deep, proprioceptive (tendon, periosteal, articular reflexes).
- Lectures. Central nervous system (CNS), 2009
The evolution of the nervous system. Embryogenesis of the brain. The general plan of the structure of the nervous system. Structural organization of the nervous system. White and gray matter, pathways. The concept of a neuron as a structural unit of nervous tissue. Morphology, types of neurons. Neuroglia, structure, types, functions. Astrocytes, oligodendrocytes, microgliocytes. Nerve fiber. The structure, types, functions. Myelin and
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- The autonomic nervous system and the main syndromes of damage
The autonomic (autonomous) nervous system regulates all internal processes of the body: the functions of internal organs and systems, glands, blood and lymph vessels, smooth and partially transversely striated muscles, and sensory organs. It provides homeostasis of the body, i.e. relative dynamic constancy of the internal environment and the stability of its basic physiological functions
- Percutaneous catheterization of peripheral veins
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- THE ROLE OF MUSCULAR TISSUE IN THE CONDUCT OF INFORMATION IN ANATOMIC DAMAGE OF THE SPINAL CORD
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- Percutaneous vein catheterization
1. Indications: * intravenous administration of drugs; * intensive infusion-transfusion therapy. 2. Equipment: hand arm, adhesive tape, tourniquet, cotton balls with alcohol, 0.9% sodium chloride solution, povidone iodine ointment, butterfly needle 23-25 gauge or catheter on a 2224 gauge needle (Angioeath). 3. Technique of implementation: 3.1. Butterfly needle, choose the right vessel; - veins
- TRACHEA AND BRONCHES
Trachea (trachea) - an unpaired organ through which air enters the lungs and vice versa (Fig. 80). The trachea has the form of a tube 9-10 cm long, somewhat compressed in the direction from front to back; its diameter is on average 15-18 mm. The basis of the trachea is 16-20 hyaline cartilaginous semirings, interconnected by annular ligaments. Trachea begins at the level of the lower edge of the VI cervical
- CLINICAL ANATOMY OF THE LARYNX
The larynx is a hollow organ that consists of a cartilaginous skeleton, ligamentous apparatus, and own muscles. The laryngeal cavity is lined with a mucous membrane from the inside. The larynx has the appearance of a short socket located above the trachea at the level of the bodies of IV, V and VI cervical vertebrae. However, when swallowing and voice formation, it significantly passes the specified boundaries, shifting up and down. Organ mobility
- Internal organs of the chest, abdomen and pelvic cavity of the mare from the left (1)
The following pages of illustrations are mainly associated with the internal organs in the body cavities (chest, abdominal and pelvic) of the mare and stallion. The first figure is actually a direct continuation of the “preparation” shown in the last of the muscle illustrations (Fig. 18.2). Intercostal muscles were removed from the spaces between the ribs, opening the chest and exposing the lung. In a stomach