reticular formation

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Related to reticular formations: Hippocampus

re·tic·u·lar for·ma·tion (RF),

a massive but vaguely delimited neural apparatus composed of closely intermingled gray and white matter and extending throughout the central core of the brainstem and into the diencephalon; the term refers to the large neuronal population of the brainstem that does not comprise motoneuronal cell groups or cell groups forming part of specific sensory conduction systems; its neurons generally have long dendrites and heterogeneous afferent connections, which is why the formation is often called "nonspecific"; the reticular formation has complex, largely polysynaptic ascending and descending connections that play a role in the central control of autonomic (for example, respiration, blood pressure, and thermoregulation) and endocrine functions, as well as in bodily posture, skeletomuscular reflex activity, and general behavioral states such as alertness and sleep.

reticular formation

n.
A diffuse network of white longitudinal nerve fibers interspersed with gray matter, located in the brainstem, that regulates various autonomic functions, such as sleep and waking.

reticular formation

a small, thick cluster of neurons nestled within the brainstem, including the medulla that controls the level of consciousness and other vital functions of the body. The reticular formation constantly monitors the state of the body through connections with the sensory and motor tracts. Certain nerve cells in the formation regulate the flow of hydrochloric acid in the stomach. Other cells regulate swallowing, tongue movements, and movements of the face, eyes, and tongue.

re·tic·u·lar for·ma·tion

(rĕ-tik'yū-lăr fōr-mā'shŭn)
A massive but vaguely delimited neural apparatus composed of gray and white matter extending throughout the central core of the brainstem into the diencephalon; the large neuronal population of the brainstem that does not compose motoneuronal cell groups or cell groups forming part of specific sensory conduction systems; its neurons generally have long dendrites and heterogeneous afferent connections; the reticular formation has complex, largely polysynaptic ascending and descending connections that play a role in the central control of autonomic (respiration, blood pressure, thermoregulation) and endocrine functions, as well as in bodily posture, skeletal muscle reflexes, and general behavioral states such as alertness and sleep.
Synonym(s): formatio reticularis [TA] , reticular substance (2) .
[L. formatio reticularis]

reticular formation

A network of islets of grey matter, consisting of large and small nerve cells and their connections, scattered throughout the brainstem and extending into the THALAMUS and HYPOTHALAMUS. The formation receives information from many other parts of the brain and is concerned with alertness and direction of attention to external events, as well as sleep. It has a major effect on the sensory and motor systems.

reticular formation

the part of the CNS that consists of small islands of grey matter separated by fine bundles of nerve fibres running in all directions.

reticular formation

fibrous, three-dimensional, mesh-like structure, e.g. plantar fat pad