Basics Of The cNS Flashcards
What is learning in a neurological sense?
The process whereby strengths of synapses are changed to match up a stimulus with an appropriate behaviour
What is emergence?
Complex behaviour emerges from interactions of individual relatively simple units
What makes up the CNS?
brain:
Cerebral hemispheres
Brain stem
Cerebellum
& Spinal cord
Blood brain barrier present
What makes up the PnS?
Dorsal(sensory) and ventral (motor) roots join to make
Spinal nerves
Peripheral nerves
No blood brain barrier
What does the shape of the Brain mean for the location of ventral and dorsal structures?
Brain flexes at around midbrain so superior part of hemisphere is dorsal and inferior is ventral
Parts of the brain stem (superior to inferior) and their function
(Optic chiasm just superior)
Midbrain (mesencephalon) - eye movements and reflex responses to sound and vision
Pons (metencephalon) - feeding (trigeminal nerve) and sleep e.g. sucking reflex
Medulla Oblongata (myelencephalon) - cardiovascular and respiratory centres, contains major motor pathway (medullary pyramids which ultimately decussate)
what separates the brain?
Sulcus/ sucking - groove/ furrow separating adjacent gyri
Gyrus/ gyri - ridge/ fold in brain (tube)
Fissure - large crack or split between adjacent large areas
What does the central sulcus separate?
The anterior ( motor ) and posterior (sensory) Brain
we walk forwards
Also separates the frontal, parietal and temporal lobes
What are the lobes of the brain and what’s their function? What about the cerebellum?
Anterior = frontal - higher cognition, motor function and speech
Posterosuperior = parietal - sensation, spatial awareness
Anterioinferior= temporal - memory, smell, hearing (under great longitudinal fissure)
Posteroinferior= occipital - vision
Below hemispheres and posterior= cerebellum - co-ordination and motor learning
Inferior cerebral hemisphere, central structures
Anterior to posterior
Optic chiasm - deccasation (crossing) of visual fibres
2 unci (singular uncus)- part of temporal lobe that can herniate, compressing the midbrain. If brain swells it can squash cranial nerve (close to 3rd) or the olfactory cortex (smell)
2 Medullary pyramids - location of descending motor fibres (each around 1 million axons) control muscles
Medial cerebral hemisphere structures
Superior to inferior
Corpus callous (fibres connecting the two cerebral hemispheres) - women bigger, damage -> alien hand syndrome
Thalamus - sensory relay station projecting to sensory cortex, conscious perception
(Just superior to thalamus) hypothalamus - homeostasis centre
