4. Thalamocortex Flashcards
What is the THALAMOCORTEX
Thalamus + cerebral cortex, with their bidirectional connections
Where is the THALAMUS located?
- Dorsral to the ventral portion of the 3rd ventricle
- Medial to internal capsule
Main function of the THALAMUS
- RELAY station for sensory and motor signals. Integration and Processing of info before projecting to the cerebral cortex
- Makes up most of the DIENCEPHALON (thalamus, epithalamus, subthalamus, hypothalamus, metathalamus)
What are the two MEDULLARY LAMINAE of the thalamus (slide 5)
Layers of white matter dividing the thalamic nuclei
- EXTERNAL medullary lamina
- Separates the thalamus from internal capsule
- Contains projection fibres - INTERNAL medullary lamina
Separates thalamus in its groups of nuclei:
- Lateral vs medial thalamic nuclei
- Rostral vs caudal thalamic nuclei
- Interlaminar (midline) thalamic groups
Nucleus of the ROSTRAL thalamic group
- Rostral thalamic nucleus (limbic system)
Nucleus of the MEDIAL thalamic group
- Medial dorsal nucleus
Nuclei of the LATERAL thalamic group (dorsal, ventral and ventral caudal divisions)
DORSAL Tier
* Dorsolateral nucleus
* Caudolateral nucleus
* Pulvinar nucleus
VENTRAL tier
* Ventral rostral nucleus (extrapyramidal)
* Ventral lateral nucleus (cerebellum)
VENTRAL CAUDAL group
* Ventral caudal medial nucleus (cranial nerves)
* Ventral caudal lateral nucleus (spinal nerves)
Nucleus of the CAUDAL thalamic group
- Medial geniculate nucleus (auditory, vestibular)
- Lateral geniculate nucleus (vision)
Nucleus of the MIDLINE (intralaminar) thalamic group
- Central medial nucleus
- Paraventricular nucleus
What is the thalamic RETICULAR nucleus
- Borders the internal capsule (laterally) and external medullary lamina (medially)
- Receives ARAS sensory afferents
- Projects to thalamic association areas
What are the 3 projection systems of the thalamus
- Direct cortical projection system
- Diffuse cortical projection system
- Thalamic reticular formation
Memorize table slide 17
Good luck
Location of FRONTAL lobe
- Rostral to cruciate sulcus
Location of TEMPORAL lobe
- Ventrolateral aspect of cerebrum (includes sylvian gyrus)
Location of PARIETAL lobe
- Caudal to cruciate sulcus
- Dorsal to sylvian gyrus