formatio reticularis


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Related to formatio reticularis: Pontine reticular formation

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.

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]

formatio reticularis

The dorsal part of the medulla oblongata.
See also: formatio