MA - Neuroanatomy II Flashcards
What are the 7 main divisions of the brain?
- Cerebrum
- Diencephalon
- Brainstem
- Midbrain
- Pons
- Medulla
Cerebellum
What lies in grey matter and in white matter?
- Cell bodies in grey matter
- Myelinated axons in white matter
What are the 3 brain planes?
- Coronal (ear to ear vertical)
- Saggital (nose to back)
- Horizontal (ear to ear axial)
What does rostral and caudal refer to?
Rostral- Towards the Head-end of an animal
Caudal- Towards the Tail-end of an animal
What are the 3 protective layers within the meninges?
- dura: superficial most and strongest, usually in contact with bone
- arachnoid: adhered closely to dura, web-like in appearance
- pia: deepest layer, in direct contact with CNS tissue
What are 2 features of the CSF
- Clear, cell-free fluid produced by the choroid plexus (ependymal cells)
- Circulates in the subarachnoid space (between arachnoid and pia)
Where do the 4 afferent inputs into the Cerebral Hemispheres come from?
- Ascending information from the thalamus
- Ascending information from the brainstem and other parts of the forebrain, also the hypothalamus
- Axons travelling between hemispheres (commissural fibres)
- Information from the ipsilateral cortex (same side)
What are the 4 Cerebral hemisphere outputs?
Always is excitatory information (uses glutamate)
- All parts of cortex project to thalamus
- Axons from motor & somatosensory cortices project to basal ganglia
- Axons project to the brainstem (nuclei) and spinal cord
- Axons project to contralateral hemisphere; axons project to ipsilateral hemisphere
What are 3 features of the brainstem?
- Serves as a conduit for ascending & descending tracts connecting the spinal cord to higher centres (cerebrum, cerebellum)
- Contains important reflex centres associated with control of respiration, heart rate & blood pressure, and consciousness
- Contains cranial nerve nuclei
What are 7 functions of the cerebellum?
- Integrates ascending (proprioceptive) information, feeds back to cerebral cortex to refine movement
- Modifies movement (compares sensory information with pre-motor information)
- Maintenance of upright posture
- Maintenance of the tension or firmness (i.e., tone) of the muscle
- Aids the cerebral cortex in planning sequential movements to make smooth progressions from one movement to the next
- Synergy of Movement – Motor coordination
- Balance
Where are the 4 cerebellar inputs from?
- Spinal cord
- Cerebellar cortex
- Vestibular system
- Motor systems in neocortex
What are the 4 cerebellar outputs?
- Vestibular systems
- Brain stem
- Muscle spindles
- Motor and pre-motor cortices
Dorsal root vs Ventral root
- A dorsal root (posterior) through which afferent fibres enter
- Cell body in DRG
- A ventral (anterior) root through which the efferent fibres leave
- Cell body in anterior horn of spinal cord
What are 4 features of innate behaviour?
- Survival mechanism
- Inherited pre-set behaviour that does not require learning
- The simplest type of animal behaviour. Performed without conscious thought
- Usually follow a specific pattern
What are 5 features of a reflex arc?
1) receptor (site of stimulus)
2) sensory neuron (transmits stimulus)
3) integration centre (can be mono or polysynaptic)
4) motor neuron (conducts impulse to effector)
5) effector (muscle or gland)
