CNS structures Flashcards
Identify the following:
- Thalamus
- Midbrain
- Pons
- Medulla
- Spinal cord
What are the 4 main subdivisions of the thalamus?
Explain the complex collection of nuclei?
and describe the structure (slide 4)
- Dorsal thalamus
- “relay” centre for sensory and motor information - Ventral (sub)thalamus
- Epithalamus
complex collection of nuclei- medial/ lateral/ anterior
- Lateral group incl geniculate nuclei and ventral posterior nucleus
- Anterior group- part of limbic system (emotional ascpects)
- Medial group- hypothalamic links, ocntrol of mood & emotions
Provide 6 key facts about the hypothalamus.
and describe the structure (slide 5)
1- Regulates:
- homeostasis
- energy metabolism (including feeding & temp)
- cardiovascular output
- reproductive activity
2- Outflow -> “autonomic centres” in the brainstem.
3- Responses to threatening situations
Provide 5 key facts about the amygdala.
and describe the structure (slide 6)
- Located deep in the anterior- medial part of the temporal lobe
- Rostral to hippocampus
- Consists of 3 main subdivisions (nuclei)
- Information from all sensory systems, from all lobes and from the hippocampus
- Fear and aggression
Provide 6 key facts about the hippocampus.
and describe the structure (slide 7)
- Located in the Medial temporal lobe
- Behind the amygdala
- Folded structure
- Consolidation of memory
- Information goes to hypothalamus and mammilary bodies via fornix
- Amnesia, alzheimer’s disease, korsakoff’s syndrome
Provide 3 main key facts about the midbrain
describe the structure (slide 8)
- Dorsal (tectum)
- Superior colliculi (visual info)
- Inferior colliculi (auditory info) - Ventral (tegmentum)
- Substantia nigra
- Red nucleus (motor control)
-Also periaqueductal gray, cerebral peduncles
Provide 6 key facts about the Pons
Describe the structures of the pons (slide 9)
- Connects the cerebrum to the cerebellum like a bridge
- White matter fibres cross on ventral surface
- Fibres to/ from cerebellum on dorsal surface
- Reticular formation
- Locus coeruleus
- Postural control
Provide 6 key facts about the Medulla.
Contains a range of diverse structures as well as motor nerves:
1. Corticospinal tract: medullary pyramids (motor pathway)
2. Cochlear nuclei & superior olive (auditory)
3. Gustatory nuclei (taste)
4. Somatosensory nuclei
5. Reticular formation (respiratory control)
6. Raphe nucleus (5-HT)
Provide 4 key facts about the Cerebellum & explain cerebellar ataxia.
Name the 3 main regions of the Cerebellum
- Peduncles: connection to midbrain, pons and brainstem
- Cerebellar cortex, deep cerebellar nuclei
- “Motor loop” with upper motor neurons
- Detection & correction of “motor error”
- Cerebellar ataxia
3 main regions:
1. Cerebrocebellum- Region of highly skilled movements
2. Spinocerebellum- Movement of distal and proximal muscles
3. Vestibulocerebellum- Regulation of movements for posture & control
Describe & explain the development of the cerebellum
- Forebrain, Midbrain & hindbrain
Explain the differentiation that occurs in the hindbrain
(rhombic lips, pons, fourth ventricle, cerebellum)
Explain the importance of Cerebellar patterning
- Important for correct placement of cellular layers
- Cerebellum is a 3 layered structure (unlike cerebral hemispheres- easily recognisable cell layers)
- Granule cells, Purkinje cells
Medulloblastoma:
-canerous transformation of the cerebellar granule cells (again, linked to shh signalling)
-60% survival rate
-Occurs ever 1 in 50,000 to 1 in 100,000
