Sistemul Reticulat Activator Ascendent

The ascending and descending reticular activating system.

Sistemul reticulat activator ascendent. The ascending reticular activating system aras also known as the extrathalamic control modulatory system or simply the reticular activating system ras is a set of connected nuclei in the brains of vertebrates that is responsible for regulating wakefulness and sleep wake transitions. El exagerează reflexele medulare şi cele din trunchiul cerebral. There are two portions to the system. See also cerveau isolé.

Sistemul reticulat descendent facilitator activator srdf trimite eferenţe spre măduva spinării în special către motoneuronii γ şi α. These neurons connect up with various other parts of the brain. Most neurons at the pontomesencephalic junction that participate in these pathways are located in monoaminergic and cholinergic cell groups. The ascending fibres of the reticular formation in the brainstem defined functionally rather than anatomically according to their control of the level of physiological arousal or activation of the cerebral cortex essential for wakefulness attention and concentration.

The ascending reticular activating system theory proposed that neurons in the upper brainstem reticular formation project to forebrain targets that promoted wakefulness. A loose network of neurons and neural fibers running through the brain stem make up the reticular activating system. Sistem reticulat activator ascendent sistem reticulat activator ascendent systeme reticule activateur ascendent reticular activating system. Fiziologic reprezentat anatomic de neuroni ai formatiunii reticulate rostrale localizati bilateral tn materia cenusie medial teg mentala de la bulb la diencefal.

Sistemul reticulat activator ascendent are legaturi cu nucleii talamici reticulari si intralaminari de la care pleaca proiectii corticale difuze. The ascending reticular activating system projects to the intralaminar nuclei of the thalami which projects diffusely to the cerebral cortex. Sistemul reticulat ascendent inhibitor srai are o acţiune de reducere a activităţii corticale. The ascending projections of the reticular activating system enhance the attentive state of the cortex and facilitate conscious perception of sensory stimuli.

The reticular activating system is located in the brain stem.