Functional regions of the brain Flashcards
Sulci=
grooves
Gyri=
bumps
What surrounds the central sulcus
the precentral gyrus and postcentral gyrus
What gyrus forms the primary motor cortex
precentral gyrus
What gyrus forms the primary somatosensory cortex
The postcentral gyrus
What is special about the primary somatosensory and primary motor cortexes
they have fibres that bridge the gap over the central sulcus so they can communicate between each other.
Homunculi=
arrangement of the body portrayed in the cortex
What is represented most laterally in the hemispheres
the head and face
What is represented over the top middle of the hemispheres
the trunk
What limbs are represented over the midline of the cortex
lower limbs
Where are the upper limbs always represented (except in 2 places)
medial to the lower limbs
What places are the lower limbs more medial than the upper limbs
the primary sensorimotor cortices and the posterior columns
In the corticospinal tract which tract decussates at the medullary pyramids
lateral cortical spinal tract
In the corticospinal tract which tracts don’t decussate in the medulla
anterior corticospinal tract
CNS signs and symptoms are usually _______ to the lesion
contralateral
PNS signs and symptoms are usually ______to the lesion
ipsilateral
What is special about the face
it has a split motor neuron
One for upper and lower face
The upper face isn’t affected destroying 1 motor neuron
Cortical or internal capsule lesions give rise to
mixed sensory & motor outcomes
For a lesion of the internal capsule to only have unimodal (Motor or sensory not both) it has to be
very small
Mixed motor and sensory symptoms suggest
the lesion is higher up (internal capsule or cortex) or a spinal nerve
What is the difference between a cortical lesion of the arm/ leg or a lesion at the pyramidal decussation
same symptoms but cortical arm/leg= some sensory + motor issue
pyramid= purely motor
in upper motor neuron lesions you get
hyperreflexia, hypertonia, spastic paralysis
In lower motor neuron lesions you get
hyporeflexia, fasciculations, flaccid paralysis
Lesions in the thalamus are always
contralateral (have lots of effects, sensory and motor.
Most ascending pathways have a synapse in the_____
Thalamus
What could lesions in the thalamus or cortex cause
contralateral hemi-anesthesia
What is contralateral hemi-anesthesia
losing sensation over the opposite half of the body
The vestibular cerebellum is also called
Flocculondular system
Where is the flocculondular (vestibular cerebellum) found
anterior aspect of the cerebellum
Another name for the Spinocerebellum
Paleocerebellum
Where is the spinocerebellum found (paleocerebellum)
strips either side of the vermis (anterior part of the hemispheres
Another name for the cerebral cerebellum
neocerebellum
What movements is the vestibular cerebellum important for
equilibrium and muscle tone
What movements is the spinocerebellum important for
propulsive, control/coordination
What movements is the cerebral cerebellum important for
voluntary movements, driving, walking (learned movements)
Name 2 deep cerebellar nuclei
Dentate and fastigial
Where do outputs from the cerebellum go
brainstem cerebral cortex
The cerebellar represents the body on each hemisphere
ipsilaterally
Cerebellar lesions always result in symptoms on the____side
same
What are movement disorders from basal ganglia dysfunction often referred as
extrapyramidal syndromes
Do the basal ganglia and cerebellum connect to LMN
NO
Dorsolateral=
distal muscles
Ventromedial=
proximal muscle s
What type of movements does the pyramidal system control
voluntary
What types of things does the extrampyramidal system control
maintain posture and balance
prior motor skills (learned)
Compensatory
