Overview Of The Nervous System Flashcards
What is the central nervous system?
Regions of the nervous system that are encased in bone (brain and spinal cord)
What is the peripheral nervous system made up of?
Autonomic and somatic nervous system
What is the autonomic nervous system made up of?
Sympathetic and parasympathetic
What is the autonomic nervous system?
Component of the peripheral nervous system that is in the CVsystem, internal organs and smooth muscle
What does the autonomic nervous system control?
Heart rate, blood pressure, breathing and digestion
What does the sympathetic part of the ANS do?
Controls fight or flight
What does the parasympathetic part of the ANS do?
Rest and digest
What is the Somatic nervous system?
Part of the peripheral nervous system that is in joints and skeletal muscle
What does the Somatic nervous system control?
Voluntary, coherent movement and locomotion
What are the three main regions of the Brain?
Forebrain
Brain stem
Cerebellum
What are the two parts of the forebrain?
Telencephalon (cerebrum)
Diencephalon
What are the parts of the brain stem
Midbrain
Pons
Medulla oblongata
What is the cerebrum?
Largest part of the forebrain that comprises the cerebral cortex and several sub cortical structures
What is the cerebral cortex made up of?
Frontal lobe
Temporal lobe
Parietal lobe
Occipital lobe
What does the frontal lobe control?
Voluntary movement and behaviour
What does the temporal lobe control?
Auditory processing and interpretation (speech) and memory
What does the parietal lobe control?
Sensory processing and interpretation (touch) and equilibrium and balance of the body
What does the occipital lobe control?
Visual processing and interpretation
What are the subcortical structures?
Hippocampus
Basal ganglia
What is the hippocampus involved in?
Learning, memory formation and retrieval, regulation of the hypothalamus
Where is the hippocampus?
Deep within the temporal lobe
What does the basal ganglia control?
Regulates movement
What is the basal ganglia made up of?
Caudate
Putamen
Globulus pallidus
What does caudate + putamen form?
Corpus striatum
What does globes pallidus + putamen form?
Lentiform nucleus
What are the three types of texture in the cerebrum surface
Bumps (gyri)
Grooves (sulci)
Fissures
What does the post central gyrus control?
Somatic sensation like touch
What does the precentral gyrus control?
Voluntary movement
What is the pre and post central gyrus separated by?
The central sulcus
What does the superior temporal gyrus control?
Audition (hearing)
What is the superior temporal gyrus separated from the pre/post central gyrus by?
Lateral (Sylvian) fissure
What is anterograde amnesia and what part of the brain does it affect?
Unable to create new memories - hippocampus
What is retrograde amnesia and what part of the brain does it affect?
Generally unable to recall past memories - hippocampus
What is huntingdons and what part of the brain does it affect?
Degeneration of gaba neutrons in caudate and putamen which leads to the motor problems such as involuntary muscle jerking- basal ganglia
What is Parkinson’s and what part of the brain does it affect?
Degeneration of dopamine neurons- basal ganglia
What is the diencephalon?
Division of the forebrain between the cerebrum and midbrain
What does the diencephalon comprise of?
Thalamus and hypothalamus
What is the thalamus?
Large collection of nuclei located in the dorsal part of the diencephalon
What is the thalamus function?
Relay between sensory and motor systems and the cerebral cortex
What does the thalamus regulate?
Arousal, pain, mood, motivation and cognitive functions
What is the hypothalamus?
Small almond sized collection of nuclei located directly above the brainstem
What is the hypothalamus function?
Reproductive, fight or flight, cortisol and adrenaline release
What is synaesthesia?
A blending of information streams
Give some examples of synaesthesia
Hearing colour and feeling sounds
How does synaesthesia happen?
The stimulation of one pathway leads to the involuntary, automatic stimulation of another pathway
How do you ‘get’ synaesthesia?
Either innate or due to thalamus damage
What happens if the hypothalamus stops working?
Hypothyroidism
Hyperthyroidism
What is the brainstem?
Part of the brain that lies between the diencephalon and the spinal cord
What does the brainstem comprise?
Midbrain
Pons
Medulla oblongata
Where is the midbrain?
Near the top of the brainstem
Where is the pons?
In between the midbrain and medulla oblongata
Where is the medulla oblongata?
Bottom of brainstem above spinal cord
What does the midbrain control?
Eye movements
Auditory and visual processing
What does pons control?
Relay of motor information from cerebral hemispheres to the medulla, spinal cord and cerebellum
What does the medulla oblongata control?
Cardiovascular and respiratory homeostasis
Reflexive actions
What is the definition of brainstem dead?
Unable to regain the consciousness or breath without the support of an artificial life support machine
What is locked-in syndrome?
Awake and conscious but no means of producing speech, limb or facial movements
What causes brainstem death?
Loss of blood circulation to all brainstem regions
What causes locked in syndrome?
Loss of blood circulation to pons
What is the cerebellum
A prominent brain structure that accounts for approx 10% of the human brains volume
What does the cerebellum do?
Doesnt initiate movement but detects differences between an intended difference and actual movement
Aids the motor cortex to produce precise and coordinated movement
The function of the cerebellum is conserved across the animal kingdom- how has this been shown?
Important in synchronisation or movement with musical rhythm - REMEMBER RONAN THE SEA LION
What is the spinal cord?
Found within the vertebral column with spinal nerves communicating with the cord via notches between the vertebrae
Where are cervical vertebrae located and how are they named?
Neck
C1-C7
Where are thoracic vertebrae located and how are they named?
Ribs
T1-T12
Where are lumbar vertebrae located and how are they named?
Lower back
L1-L5
Where are sacral vertebrae located and how are they named?
Pelvic area
S1-S5
What is the dorsal root?
A bundle of sensory neuron axons that carry sensory information into the spinal cord
What is the ventral root?
A bundle of motor neuron axons that carry information away from the spinal cord to striated muscle
What is the grey matter comprised of and divided into?
Comprised of neuronal cell bodies divided into horns
What is the white matter comprised of and divided into?
Comprised of axon bundles divided into columns
What does a motor neuron pool do?
Directly innovate skeletal muscle and allow for movement
What does a motor track do?
Derived from descending systems influenced by cerebellum and basal ganglia
What is tetraplegia?
Full or partial loss of sensation and movement in all four limbs and torso
What is tetraplegia caused by?
Damage in the cervical C1-C7 area
What is paraplegia?
Full or partial loss of sensation and movement in both legs (and torso)
What is paraplegia caused by?
Damage in the thoracic (T1-T12), lumbar (L1-L5) or sacral (S1-S5) area
What are the meninges?
3 membranous layers that cover the brain and spinal cord
What is the order of the 3 types of meninges (outer-> inner)
Dura mater
Arachnoid membrane
Pia mater
What is the dura mater made of?
Tough inelastic layer
How is the arachnoid membrane separated from the dura mater?
Subdural space
How is the pia mater separated from the arachnoid membrane
Subarachnoid space filled with cerebro-spinal fluid
What is the function of the meninges?
- primarily the protection of the brain and spinal cord
- passage of CSF- ventricular system
- support of cerebral and spinal blood vessels- vasculature system
What is the ventricular system?
A series of interconnected CSF filled spaces that lie at the core of the forebrain and brain stem
What does the ventricular system comprise?
Lateral ventricles- paired structures sprout from the third ventricle
Third ventricle
Fourth ventricle - extends from the cerebral aqueduct
What is the function of the ventricular system?
Protection of Brain (cushion for shocks)
Transport (nutrients, waste products)
Other functions include regulation of buoyancy
What produces CSF?
Choroid plexus
What is the vasulature system?
Two pairs of arteries supply blood to the Brain: internal carotoid arteries and vertebral arteries
What is derived from the internal carotid arteries and what part of the brain does it supply?
Anterior circulation
Supplies the forebrain (cerebrum and diencephalon)
What is derived from the vertebral arteries and what part of the brain does it supply?
Posterior circulation
Brainstem, cerebellum and upper spinal cord
What is the function of the vasculature system?
Delivery of oxygen
Removal of carbon dioxide
Transport (nutrients, waste products)