thalamus


Also found in: Dictionary, Thesaurus, Medical, Legal, Wikipedia.

thalamus

(thăl`əməs), mass of nerve cells centrally located in the brainbrain,
the supervisory center of the nervous system in all vertebrates. It also serves as the site of emotions, memory, self-awareness, and thought. Anatomy and Function
..... Click the link for more information.
 just below the cerebrum and resembling a large egg in size and shape. The thalamus is a routing station for all incoming sensory impulses except those of smell, transmitting them to higher (cerebral) nerve centers. In addition, it connects various brain centers with others. Thus the thalamus is a major integrative complex, enabling sensory stimuli to evoke appropriate physical reactions as well as to affect emotions. With the hypothalamushypothalamus
, an important supervisory center in the brain, rich in ganglia, nerve fibers, and synaptic connections. It is composed of several sections called nuclei, each of which controls a specific function.
..... Click the link for more information.
, the thalamus establishes levels of sleep and wakefulness. It is also vital to the neural feedback system controlling brain wave rhythms.

Thalamus

 

a conglomerate of the nuclei of gray matter (nerve cells) in the brain, located between the mesencephalon and the cerebral cortex; it is the main part of the diencephalon.

The thalamus developed for the first time in bony fish. In ontogenesis it develops from the prosencephalon sac. The thalamus is a nucleus in which afferent nerve impulses coming from all the sense organs (except the olfactory organs) gather. Each type of sensory pathway has its own specific nuclei (lateral group) in which the impulses are transmitted from one nerve cell to another and are transferred to the appropriate zone of the cerebral cortex. Associative nonspecific nuclei (medial group) receive stimuli from specific nuclei of the thalamus and from nonspecific structures of the diencephalon, mesencephalon, and medulla oblongata and transmit them to various subcortical and cortical neurons. The thalamus is involved in primary analysis and synthesis of all stimuli entering the brain from the neuroreceptors. In lower vertebrate animals the thalamus ensures performance of all necessary reflexes; in mammals and man the higher center of integration is the cerebral cortex. Under the thalamus lies the hypothalamus.

IU. A. FADEEV

thalamus

[′thal·ə·məs]
(anatomy)
Either one of two masses of gray matter located on the sides of the third ventricle and forming part of the lateral wall of that cavity.

thalamus, thalamium

In early Greek architecture, an inner room or chamber, esp. the women’s apartment.
References in periodicals archive ?
While anomia is generally associated with left dorsomedial thalamus lesions, lesions of the ventrolateral and ventral anterior regions lead to paraphasic disorders.
If one is interested in how the brain is affected by LSD, you need look no further than our friend, the thalamus.
By studying the long-term impact of DBS on the anterior nucleus of the thalamus, we hope to understand even further how seizures can be controlled and reduced," said Professor Paul Boon, Professor of Neurology at the Department of Neurology, Ghent University Hospital in Belgium who is the chair of the steering group behind the MORE Registry.
It connects the cells receiving input from the eye to the lateral geniculate nucleus, an important relay station in the brain's thalamus.
Using magnetic resonance imaging, the authors determined that occupational exposure to Mn was associated with elevated GABA levels in the thalamus and adjacent basal ganglia.
In this procedure, a wire, or stimulating electrode is inserted into the area of the brain called the thalamus," explains Ahlskog.
6) Autopsy series in aceruloplasminemia have demonstrated severe iron deposition and extensive neuronal loss within the neostriatum, dentate nucleus, and thalamus and marked loss of Perkinje cells within the cerebellar cortex.
Experts in the US believe a sensory gateway in the brain called the thalamus plays a key role in blocking out sound during sleep.
The components of the DBS system include a neurostimulator that connects to two leads that are implanted in the anterior nucleus of the thalamus.
Activation of the midbrain, cerebellum, thalamus, and midcingulate, primary and secondary sensory, inferior parietal, insula and prefrontal cortices correlated with reported changes in pain with hypnotic and non-hypnotic suggestion.
Those areas were in the basal ganglia, hippocampus, thalamus and amygdala, and the thalamus.
The pathological lesions in JE are foci of neuronal degeneration with parenchymal and perivascular inflammatory responses are found principally in thalamus and brain stem, as well as in the hippocampus, temporal cortex, cerebellum, and spinal cord6.