2. Structure of the CNS Flashcards
What is the pyramidal system?
Upper motor neuron starts in the pre-central glyrus
Passes through the pyramids of the medulla
Conscious movement
What is the extrapyramidal system?
Upper motor neuron starts in other brain centre nuclei (basal ganglia)
Don’t pass through pyramids
Fine tune movement
What is the cerebellum responsible for?
Balance
Tone
Posture
Co-ordination and planning movement
What disease affects the cerebellum?
Transient cerebellar disease: drunk
Associated with intention tremor
What are the functions of the basal ganglia?
Diffuse set of nuclei responsible for allowing/stopping movements
Name the basal ganglia
Nucleus accumbens Caudate Putamen Globus pallidus Subthalamic nucleus Substantia nigra
What disease affects the basal ganglia?
Parkinson’s
Associated with resting tremor
What is the function of the thalamus?
Sensory relay station
Where is the thalamus located?
Either side of the third ventricle
What type of information travels in dorsal columns?
Touch
Proprioreception
What path is taken by nerves conveying touch and proprioception?
Dorsal columns:
First nerve enters and goes up to medulla
Second decussates in the medulla, goes to thalamus
Third nerve up to somatosensory cortex
What type of information travels in the spinothalamic tract?
Pain
Temperature
What path is taken by nerves conveying pain and temperature?
Spinothalamic tract
First nerve synapses with second in spinal cord
Second goes to thalamus
Third goes to somatosensory cortex
What is contained in the limbic system?
Cingulate gyrus
Hippocampal formation
Amygdala
What is the function of the limbic system?
Emotion
Memory
Maintain attention to surroundings
Drives feeding and mating behaviour
What is the flow of CSF through the ventricular system?
Lateral ventricles Intraventricular foramen of Monro 3rd ventricle/cavity of diencephalon Central aqueduct of sylvius 4th ventricle -Foramina of Magendie -Foramina of Lushka
Cranial Nerve 1
Smell
Cranial Nerve 2
Vision
Cranial Nerve 3,4,6
Eye movement
Cranial Nerve 5
Facial and scalp sensation
Mandibular movements
Cranial Nerve 7
Facial expression
Cranial Nerve 8
Hearing
Balance
Cranial Nerve 9,10
Swallowing
Phonation
Cranial Nerve 11
Neck and head movement
Cranial Nerve 12
Tongue movement
What does the cauda equina activate?
Bladder
Bowel
Sexual organs
Legs
What are the signs of Cauda Equina Syndrome?
Lower back pain
Pain radiating down leg
Loss of bowel or bladder control
Weakness, tingling and numbness in saddle region
What causes Cauda Equina Syndrome?
Slipped disc
Tumours near spine
Injury
