User Contributed Dictionary
Adjective
- Of or pertaining to the tectum
Extensive Definition
The tectum (Latin: roof) is a region of the
brain, specifically the
dorsal part of the mesencephalon
(midbrain).
It is derived in embryonic development from the
alar
plate of the neural
tube.
Colliculi
In adult humans it is present only in the mesencephalon as the inferior and the superior colliculi.- The superior colliculus is involved in preliminary visual processing and control of eye movements. In non-mammalian vertebrates it serves as the main visual area of the brain, functionally analogous to the visual areas of the cerebral cortex in mammals.
- The inferior colliculus is involved in auditory processing. It receives input from various brain stem nuclei and projects to the medial geniculate nucleus of the thalamus, which relays auditory information to the primary auditory cortex.
Both colliculi also have descending projections
to the
paramedian pontine reticular formation and spinal cord,
and thus can be involved in responses to stimuli faster than
cortical processing would allow. Collectively the colliculi are
referred to as the corpora
quadrigemina.
Related terms
The term "tectal plate" (or "quadrigeminal plate") is used to describe the junction of the gray and white matter in the embryo. (, )External links
- Diagram
- [http://137.222.110.150/calnet/UMN/image/tectum%20&%20tegmentum%20of%20midbrain-fixed%20photo.jpg Photo]
tectal in German: Tectum
mesencephali#Mittelhirndach
tectal in Thai: เทคตัม
tectal in Spanish: Téctum