Nervous system

Hippocampus

The hippocampus is a complex structure deep in the temporal lobe of the brain: between its medial side and the lower horn of the lateral ventricle, forming one of its walls.

The duration of the phases of healthy sleep in children and adults: what should be?

The human body needs to rest regularly. Night rest allows you to stabilize blood circulation, normalize metabolic processes, neutralize the effects of stress.

Memory: neurochemical mechanisms of memory

Although the molecular mechanisms of the functioning of a single nerve cell have been studied in many of their manifestations and the principles of organization of interneuronal connections have been formulated, it is still unclear how the molecular properties of neurons provide storage, reproduction and analysis of information-memory.

Mediators of the nervous system (neurotransmitters)

Neurotransmitter (neurotransmitter, neurotransmitter) is a substance that is synthesized in a neuron, contained in presynaptic endings, released into the synaptic cleft in response to a nerve impulse and acts on special sites of the postsynaptic cell, causing changes in the membrane potential and cell metabolism.

Synapses in the nervous system

The concept of "synapse" was introduced at the end of the XIX century. C. Sherrington, implying by this term a structure that mediates the transmission of a signal from the end of the axon to the effector - the neuron, the muscle fiber, the secretory cell.

Blood-brain barrier

The blood-brain barrier is extremely important for the maintenance of brain homeostasis, but many questions concerning its formation are still not fully understood. But already now it is absolutely clear that the BBB is the most pronounced on the differentiation, complexity and density of the histohematological barrier.

Myelin

Myelin is a unique formation, the organization of which allows you to conduct an electrical impulse along the nerve fiber with minimal energy expenditure. Myelin sheath is a highly organized multilayer structure consisting of highly stretched and modified plasmatic membranes of Schwann's (in PNS) and oligodendroglial (in the central nervous system) cells.

Neuron

Neuron is a morphologically and functionally independent unit. With the help of processes (axon and dendrites) it makes contacts with other neurons, forming reflex arcs - links from which the nervous system is built.

The trunk of the brain

The trunk of the brain is the extension of the spinal cord in the rostral direction. The conditional boundary between them is the place where the first cervical roots and the cross of the pyramids exit. The trunk is divided into the posterior and middle brains. The first includes the medulla oblongata, the brain bridge and the cerebellum. Its continuation is the middle brain, consisting of quadruplets and cerebral legs and bordering on the intermediate brain (the thalamus, hypothalamus, subthalamus).

The defeat of the oculomotor (III) nerve (n. Oculomotorius)

Possible causes of the defeat of the III nerve: polyneuropathy and mononeuropathy (diabetes mellitus, etc.), aneurysms, tumors, tuberculomas, cerebral infarcts, encephalitis, demyelinating diseases, meningitis, trauma, infringement of the temporal lobe in the opening of the cerebellum nodule, Tholosy-Hunt syndrome, thrombosis, carotid cavernous fistula

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