5. Nervous System Flashcards
What are the two branches of the STRUCTURAL nervous system?
Central nervous system which consists of brain and spinal cord
Peripheral nervous system which consists of cranial nerves and spinal nerves
What are the two branches of the FUNCTIONAL nervous system?
- ) Somatic which is a.) motor - skeletal muscle and b.) sensory - pain, temperature, touch, pressure, proprioception and special senses
- ) Autonomic (viscera - any organs) which is a.) sympathetic and b.) parasympathetic
What is a neurone?
Nerve cell
Basic functional unit of the nervous system
Relays info between:
- different regions of the CNS
- CNS and PNS
CNS and other body systems
Label the neurone
What is a nerve?
A bundle of axons carrying information from the CNS to the rest of the body or from the rest of the body to the CNS
Where do nerves enter and level the CNS?
Cranial nerves
- 12 pairs
- arise from the brain
Spinal nerves
- 31 pairs
- arise from the spinal cord
Label the cross section of the brain
What is in the diencephalon?
Thalamus and hypothalamus
What is in the brainstem?
Pons, medulla and midbrain
What is the function of the brains folded arangement?
Increases surface area
Where is the cerebellum?
Lies posterior to brainstem
What does the cerebellum do?
Involved in maintenance of:
- balance
- posture
- muscle tone
Co-ordinates movement
What does the brain stem do?
Contains ascending and descending nerve fibre tracts
Cranial nerves III-XII arise from brain stem
Contains vital centres such as cardiovascular and respiratory centres
What does the thalamus do?
Important relay station for sensory information
What does the hypothalamus do?
Hormone secretion
Intergrating centre for ANS
Thermoregulation
Hunger and satiety centres
Thirst centre
Describe the cerebrum?
2 hemispheres
Sulci (burrows) and gyri (ridges)
Cortex is grey matter on outside of brain containing nerve cell bodies
Connecting fibres is white matter (axons with myelin make it appear white)
Basal gangli is grey matter
What and where is the longitudinal fissure?
Big sulci dividing two cerebral hemispheres
Label the lobes of the cerebrum
What does the frontal lobe do?
Motor cortex - involved in intellect, planning, mood, social judgement etc
What does the parietal lobe do?
Somatosensory cotex - general sensation and taste
What does the temporal lobe do?
Auditory cortex
What does the occipital lobe do?
Visual cortex
What do the positions s, p, i and a mean?
Superior - above
Posterior - behind
Inferior - below
Anterior - infront
Where is the primary motor cortex?
Precentral gyrus
Where is the primary sensory cortex?
Post central gyrus
Label the cerebrum
What are the symptoms of brocca damage?
Know what they want to say but struggle to say it
What are the symptoms of wernicke damage?
Words are fine but word order and language bad
What is the function of the meninges?
Protect brain from skull
How many layers of protective tissue make up the meninges?
3 dura mater on outside, arachnoid mater in middle and pia mater in middle
What is the dura mater like?
Outer layer, very durable, like big bag going around brain
What is arachnoid mater like?
Things coming off looks like spider legs, sub arachnoid space is underneath
What’s in the subarachnoid space?
CSF
What is the purpose of CSF?
Bathes brain and keeps it buoyant
What is the pia mater like?
Pia mater covers all gyri and sulci and goes in depressions
What is the ventricular system?
The ventricles are interconnecting chambers that produce CSF
Label and describe the ventricles
Lateral ventricles x2 (cerebral hemispheres)
Third ventricle (lateral walls formed by thalamus)
Cerebral aqueduct (connects 3rd to 4th ventricle)
Fourth ventricle (betwen brainstem and cerebellum)
What supplies blood to brain?
Internal carotid arteries and certebral arteries
How many pairs of cranial nerves are there?
12 pairs
Where do cranial nerves arise from?
From the brain (10 from brainstem)
What kind of fibres do cranial nerves carry?
Some carry only motor fibres, some only sensory fibres and some both, four pairs also carry parasympathetic fibres
Name the cranial nerves and their function
Nerve names: Oh Oh Oh To Touch And Feel (a) Virgin Girl’s Vagina And Hymen
Olfactory, Optic, Oculomotor, Trochlear, Trigeminal, Abducens, Facial, Vestibulocochlear (formerly Auditory), Glossopharyngeal, Vagus, Accessory, Hypoglossal
Nerve Function (Sensory, Motor, Both): Some Say Marry Money But My Brother Says Big Breasts Matter More
Describe the spinal cord?
Supported and protected by vertebral column, continuous with brain stem, terminates at the conus medullaris (level L1)
Name the spinal segments?
31 spinal segments and associated pairs of spinal nerves
from top to bottom:
8 cervical
12 thoracic
5 lumbar
5 sacral
1 coccygeal
How many layers make up the spinal meninges and what are they called?
3 - dura mater on outside, arachnoid mater middle, pia mater inside
Where is the majority of CSF produced?
Choroid plexus
Where is CSF drawn from during lumbar puncture?
Subarachnoid space at Cauda equina (horses tail)
What is the conus medullaris?
(Medullay cone) is Lower end of spinal cord
Where is an epidural injected?
On dura mater
