habenula


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habenula

 [hah-ben´u-lah] (pl. haben´ulae) (L.)
1. any frenulum, especially one of a series of structures in the cochlea.
2. a triangular area in the dorsomedial surface of the thalamus anterior to the pineal gland. adj., adj haben´ular.

ha·ben·u·la

, pl.

ha·ben·u·lae

(ha-ben'yū-lă, -lē), [TA]
1. Synonym(s): frenulum
2. In neuroanatomy, the term originally denoted the stalk of the pineal gland (pineal habenula; pedunculus of pineal body), but it gradually came to refer to a neighboring group of nerve cells with which the pineal gland was believed to be associated, the habenular nucleus. Currently, the TA term refers exclusively to this circumscript cell mass in the caudal and dorsal aspect of the dorsal thalamus, embedded in the posterior end of the medullary stria from which it receives most of its afferent fibers. By way of the retroflex fasciculus (habenulointerpeduncular tract), it projects to the interpeduncular nucleus and other paramedian cell groups of the midbrain tegmentum. Despite its proximity to the pineal stalk, no habenulopineal fiber connection is known to exist. It is a part of the epithalamus. Synonym(s): habena (3)
[L.]

habenula

/ha·ben·u·la/ (hah-ben´u-lah) pl. haben´ulae   [L.]
1. a frenulum, or reinlike structure, such as one of a set of structures in the cochlea.
2. a small eminence on the dorsomedial surface of the thalamus, just in front of the posterior commissure.haben´ular

ha·ben·u·la

, pl. habenulae (hă-ben'yū-lă, -lē) [TA]
1. Synonym(s): frenulum.
2. neuroanatomy The term originally denoted the stalk of the pineal gland (pineal habenula; pedunculus of pineal body), but gradually came to refer to a neighboring group of nerve cells with which the pineal gland was believed to be associated, the habenular nucleus. Currently, the term, as defined by TA, refers exclusively to this circumscript cell mass in the caudal and dorsal aspect of the dorsal thalamus, embedded in the posterior end of the medullary stria from which it receives most of its afferent fibers. By way of the retroflex fasciculus (habenulointerpeduncular tract) it projects to the interpeduncular nucleus and other paramedian cell groups of the midbrain tegmentum. Despite its proximity to the pineal stalk, no habenulopineal fiber connection is known to exist. It is a part of the epithalamus.
Synonym(s): habena (3) .
[L.]

habenula

pl. habenulae [L.]
1. any frenulum, especially one of a series of structures in the cochlea.
2. a triangular area in the dorsomedial aspect of the thalamus rostral to the pineal gland.
References in periodicals archive ?
This phenomenon, labeled "the disappointment circuit," occurs in an evolutionarily ancient part of the brain known as the lateral habenula.
Specifically, in experiments with rodents, UC San Diego researchers discovered that neurons feeding into a small region above the thalamus known as the lateral habenula (LHb) secrete both a common excitatory neurotransmitter, glutamate, and its opposite, the inhibitory neurotransmitter GABA.
Washington, July 29 ( ANI ): A recent study has identified the half-pea-sized human brain portion called habenula, which tracks negative expectations like painful electric shocks and shows how bad things could get.
In the proposed project we will explore the function and the architecture of neural circuits that are involved in olfactory and gustatory information processing, namely habenula and brainstem.
But like tourists exploring a strange city without a GPS map, scientists don't know how all the neural neighborhoods are connected and occasionally encounter surprising enclaves--such as a place in the brain called the lateral habenula.
Hypothalamic, dorsal raphe and external electrical stimulation modulate noxious evoked responses of habenula neurons.
University of Utah neuroscientists report that when a region of the brain called the lateral habenula is chronically inactivated in rats, they repeatedly drink to excess and are less able to learn from the experience.
Intriguingly, salience experience alters the activity in the medial globus pallidus of the basal ganglia and the lateral habenula (LHb) as well as in dopamine and serotonin neurons.
In experiments on hamsters, the antibody revealed thin nerve connections running from pineal cells to the regions called the posterior commissure and the habenula.
NERF-scientists demonstrate that the habenula, a specific part in our brain consisting of neural circuits, acts as a gate for sensory information, thus regulating behavior in response to external stimuli.
25 ( ANI ): Researchers have claimed that the lateral habenula - one of the oldest regions of the brain, evolution-wise - a region of the brain linked to depression and avoidance behaviors, has been largely misunderstood and may be integral in cost-benefit decisions.
Researchers were also able to produce the opposite effect - reduced effort in response to challenge - by stimulating prefrontal neurons that project to the lateral habenula, a region perched atop the brain stem that is thought to play a role in depression.