The reticular formation

The reticular formation (synonym: reticular substance, reticular formation) is a collection of nerve cells and their extensions, located in the brain stem, oblong and the middle brain, the hypothalamus, the thalamus.
Its name reticular formation, was due to the characteristic "net" structure, which is obvious microscopic examination.
The reticular formation has extensive morphological connection with the spinal cord, the cerebellum, the limbic brain structures and the bark of the big hemispheres. The opening of the physiological properties of the reticular formation is associated with the use of stereotactic technique (see), and electroencephalography (see).
Irritation of the reticular formation by electric current through entered in her electrodes awakens the sleeping animals and causes of generalized reaction activation EEG of a bark of the big hemispheres. The complete destruction of the reticular formation, on the contrary, causes soundly sleep in animals. The reticular formation has on the bark of the big hemispheres ascending activating influence. This changes the old concepts, according to which sensory information is supplied to the bark of a brain only lemniscomys ways, to address specific projection area. Due to the huge number of collaterals from medial lemnisci to retikuliarna formations any sensory stimulation reaches the brain not only lemniscomys ways, but generalizovannom due to excitation of the reticular formation.
A clear trigger action on the reticular formation have some humoral substances such as adrenaline and carbon dioxide.
Since the initiation of any sensory modality and many humoral materials activate reticular formation, there are grounds to speak about non-specific ascending activating effects of the reticular formation in the brain.
On the other hand, this view has changed much. Numerous experimental data laboratory P. K. Anokhin shown that the reticular formation in the reactions of various biological quality has specific ascending activating effect on the brain. Although at various biological conditions of the organism (e.g., hunger, fear, lust and so on) are experiencing generalized activation EEG, this activation always specific and has a selective attitude to drugs and various chemicals.
The reticular formation has also descending - as brake and facilitate effects on the function of the motor neurons of the spinal cord.
The reticular formation of heterogeneous by its chemical properties, and electoral its sensitivity to various chemical substances is considerably higher than other entities of the brain. Introduced into the body drugs and psychopharmaceuticals mainly operate on the reticular formation, thereby blocking its ascending activating effect on the brain cortex.
The reticular formation in turn is under the controlling influence of other upstream parts of the brain, in particular the bark of the big hemispheres.
The opening of the physiological properties of the reticular formation allows fundamentally new positions to present such problems as cortical-subcortical ratio, mechanism of action of drugs and psychopharmacological agents, mechanisms of pain, sleep and wakefulness, emotions and motivations, as well as the mechanism of formation of the conditioned reflex and other complex behaviors.