II. Definitions
- Thalamus
- Functions as a central hub for incoming sensory signals relayed to the cerebral cortex
- Motor interconnections between the Cerebellum, cerebral cortex and target peripheral Neurons
- Thalamus functionality is divided among its 9 thalamic nucleii
III. Anatomy
-
General
- Paired sensory relays
- Located in the posterior Diencephalon of the brain
- Thalamus located on each side of Third Ventricle
- Nucleii
- Ventral Posterolateral Nucleus (VPL)
- Ventral Posteromedial Nucleus (VPM)
- Anterior Thalamic Nucleus
- Portion of the Papez Circuit
- Ventral Lateral Nucleus (VL)
- Cerebellum input
- Images
Lewis (1918) Gray's Anatomy 20th ed (in public domain at Yahoo or BartleBy)
Lewis (1918) Gray's Anatomy 20th ed (in public domain at Yahoo or BartleBy)
IV. Physiology
- Thalamus acts as a relay and integrative center for sensory input
- Receives peripheral sensory signals through the Brainstem
- Communicates with the Cerebellum, Basal Ganglia and Hypothalamus
- Transmits sensory signals to the cerebral cortex
- Motor signsal from the cerebral cortex bypass the Thalamus via the Internal Capsule
V. Signs: Brain Lesion
- Contralateral sensory loss
- Behavioral changes
- Language disorder
VI. References
- Netter (1997) Atlas Human Anatomy, ICON Learning, p. 105
- Newton (1994) Am Fam Physician 49(4): 787-97 [PubMed]