Hani Revision Book Flashcards
What are the upper motor neuron signs?
Hypertonia
Hyperreflexia
Weakness with no wasting
Clonus and upgoing plantars
What are the lower motor neuron signs?
Reduced tone Weakness Wasting Fasciculations Hyporeflexia
What are the key functions of the frontal lobe?
Personality
Emotions
Broca’s area for speech formation
Precentral gyrus/premotor cortex
What are the key functions of the temporal lobe?
Memory
Wernicke’s area- language reception/comprehensions
What are they key functions of the occipital lobe?
Vision
What are the key functions of the parietal lobe?
Postcentral gyrus/Primary sensory cortex
What tract do the majority of motor pathways run in? Where does decussation take place?
Corticospinal tract-
Decussation takes place at the medulla. Begins at the precentral gyrus (motor cortex in frontal lobe) and descends in the internal capsule, decussating at the medulla. Runs along the lateral corticospinal tract to the ventral horn where it synapses with the postsynaptic neuron.
Note- Fibres that innervate axial muscles decussate in the spinal cord and descend via the anterior corticospinal tract
Where does the corticospinal tract decussate?
At the medulla
Where does the corticospinal tract begin?
Precentral gyrus or primary motor cortex
It’s in the frontal lobe
What does the spinothalamic tract carry?
Pain and temperature and crude touch- involves three neurons leading to the postcentral gyrus. (Temporal lobe)
Describe the route of the spinothalamic tract?
First order neuron synapses with second order neuron at the dorsal horn (first order neuron ascends 1-2 levels via lissauer’s fasciculus)
Second order neuron crosses to the other side via the anterior white commissure, then ascends via the spinothalamic fasciculus
Synapses with third order neuron at the thalamus
Third order neuron to the postcentral gyrus (sensory cortex)
What is the arrangement of the sensory cortex?
It’s upside down- feet are at the top and middle, face is lateral and lower down
Both are responsible for contralateral side
Where does the spinothalamic tract decussate?
The second order neuron decussates in the spinal cord via the anterior white commissure
Where does the corticospinal tract decussate?
The medulla- this is the upper motor neuron which descends from the precentral gyrus/motor cortex.
What does the dorsal column carry?
Position/Proprioception
Vibration
Fine touch
Where is the dorsal column found in the spinal cord?
Posterior spinal cord
Dorsal = Back
Which column carries coarse touch?
Spinothalamic
Which column carries fine touch?
Dorsal column
Describe the route of the dorsal columns
Carries proprioception, vibration and fine touch
First neurons- Neurones run from receptors to the dorsal horn. Ascend via the dorsal columns (Gracile and Cuneate Fasciculus) to the medulla to synapse with cuneate or gracile nucleus.
Decussation occurs at the medulla to the other side by second order neuron.
Then to the ventral posterolateral nucleus in thalamus
Then to the sensory cortex via third order neuron.
Where do the dorsal columns decussate?
Medulla oblongata
Where does the corticospinal tract decussate?
Medulla
Where does the spinothalamic tract decussate?
At the spinal cord via the anterior white commissure
Outline what the spinothalamic tract and dorsal columns carry
Spinothalamic- Pain, Temperature, Coarse Touch
Dorsal- Proprioception, Vibration, Fine touch
STC- Sit to crap
DPF- Dogs poo fast
Where is the cortical area for speech located in most people?
The left side
60-70% of left handed people it is on the left side
