Neuroanatomy Flashcards
What makes up the brainstem?
Midbrain
Pons
Medulla Oblongata
Is the connective tissue in the CNS?
No
What is the function f oliodendrocytes?
Produce myelin in the CNS
What are the 4 major glial cells in the CNS?
Astrocytes
Oligodendrocytes
Microglia
Ependymal cells
What is the roleof microglia in the CNS?
Immune monitoring and antigen presentation
What are folia?
Equivalent to gyrus in the cerebral hemisphere
What composes grey matter?
Huge numbers of neurons,celll processes, synapses and support cells
What composes white matter?
Axons (most myelinated) and their support cells
What makes up the lentiform nucleus?
Putamen
Globus pallidus
What splits the frontal & parietal lobe?
Central sulcus
What splits the parietal & temporallobes?
Lateral sulcus
What is he insula involved in?
Patient’s experience of pain
What are the layers of meninges frm superficial to deep?
Dura mater
Arachnoid mater
Pia mater
Where are neurons found in the enteric nervous system?
Myenteric plexus & submucosal plexus
How does blood from the brain drain?
Into a system of dural venous sinuses then into the internal jugular foramen
What is the end of the spinal cord calledand what vertebral level is it at?
Conus Medularis at L1/2
At which spinal levels in a small lateral horn present?
T1-L2
What does the lateral horn contain??
Preganglionic sympahetic neurones
Which tract is respnsible for finetouch and conscious proprioception?
DCML pathway
Where do fibres cross in the DCML pathway?
Medulla
Which tract is responsible for pain, temperature and deeppressure?
Spinothalamic tract
Where do fibres cross in the spinothalamictract
Segmentally
Which tract is responsible for fine, precise movement?
Corticospinaltract
Which tract is also called the pyramidal tract?
Corticospinal tract
Where do fibres cross in the corticospinal tract?
85% at caudal medula (decussation of the pyramids)
What are the 2 divisions of the corticospinal tract?
Crossed fibres - Lateral CST
Uncrossed fibres - Ventral CST (cross segmentally)
How would a CVA of the internal capsule causing a lack of descending control of the corticospinal tract present?
Hyperflexion of the upper limbs
What are the 3 extrapyramidal tract?
Tectospinal tract
Reticulospinal tract
Vestibulospinaltract
What is the function of the tectospinal tract?
Mediates reflex head and neck movement due to visual stimuli
Which tract forms the central core of the brain stem?
Reticulospinal tract
What effect do fibres originating from the pons have on movement when compared to the medulla?
Pons facilitate extensor and inhibit flexor
Medulla facilitate flexor and inhibit extensor
What is the function of the vestibulospinal tract?
Excitatory input to “antigravity” extensor muscles
What is Brown-Sequard syndrome?
Lateral hemisectionofthecord
What are the effects of a lateral hemisection of the cord?
Ipsilateral paralysis
Ipsilateral hyperreflexia & extensor plantar reflex
Ipsilateral loss of vibrator sense and proprioception
Contralateral loss of pain & temp sense
What are the 3 layers of the cerebellar cortex?
Molecular layer (outer) Purkinje cell layer (middle) Granular layer (inner)
Where do most efferent axons coming from the deep cerebellar nuclei synapse?
The thalamus
Do cerebral hemispheres influence the ipsilateral or contralateral side of the body?
Ipsilateral
What are the symptoms of a unilteral cerebellar hemisphericlesion?
Disturbance of coordination in limbs
Intention tremor
Unsteady gait in the absence of weakness or sensory loss
Symptoms of bilateral cerebellar dysfunction?
Slowed, slurred speech
Bilateral incoordination of the arms
Staggering widebased gait
What acute situation typically results in cerebellar ataxia?
Acute alcohol exposure
How does a midline cerebellar lesion present?
Disturbance of postural control (fall over when standing or sitting despite preserved limb coordination)
What are the functions of the basal ganglia?
Facilitate purposeful movement
Inhibit unwanted movements
Has a role in posture and muscle tone
What 5 masses make up the basal ganglia?
Caudate nucleus Putamen Globus pallidus Subthalamic nucleus Substantia nigra
What is the pathology of Parkinson’s disease?
Degeneration of dopaminergic neurons of the substantia nigra
Which side of the body do lesions of the basal ganglia effect?
Contralateral side
How do lesions of the basal ganglia present?
Changes in muscle tones
Dyskinesias (tremor, choea, myoclonus)
How is Huntington’s transmitted?
Autosomal dominant
What is the pathology of Huntington’s?
Progressive degeneration of the basal ganglia and cerebral cortex
Signs of Huntington’s
Chorea andprogressivedimentia
What is the corticobulbar tract?
The part of the pyramidal tract that is motor to cranialnerves
Why is unilateral deafness not a brainstem or core issue?
As superior to the cochlear nuclei some fibres are crossed and some are not
What are the 2 types of aphasia?
Broca’s & Wernicke’s
What is Broca’s aphasia?
Can understand language but have difficulty producing it
What is Wernicke’s area?
Patient’s have difficult comprehending but can manifest defects ranging from words out of order to meaningless words
