Overview of the Nervous System Flashcards
what are the two branches of the nervous system?
central NS and peripheral NS
what is the CNS made up of?
the brain and spinal cord
what is the PNS made of?
the autonomic NS and somatic NS
how many branches doe the autonomic NS have and what are the names?
2: sympathetic and parasympathetic NS
what does the parasympathetic NS control?
provides innervation to the cardiovascular system, internal organs and SM
-BP, HR, breathing and digestion
what does the sympathetic NS control?
fight or flight
what is the function of the somatic NS?
- permits voluntary coherent movement and locomotion
- innervates skin, joints, SM
what are the three main regions of the brain?
1) forebrain: the telencephalon and diencephalon
2) brain stem
3) cerebellum
what is the telencephalon?
- otherwise known as the cerebrum
- made of the cerebral cortex and other subcortical structures
what makes up the cerebral cortex?
the four lobes: frontal lobe, temporal lobe, parietal lobe and occipital lobe
what is the function of the frontal lobe?
- controls voluntary movement
- controls behaviour
- attention, planning, decision making
- motivation and emotional regulation
what does the parietal lobe control?
- sensory processing and interpretation
- proprioception: balance of the body and eqm
what is the function of the temporal lobe?
auditory processing na dinterpretation
-memory: formation of the LTM
what does the occipital lobe do?
-visual processing and interpretation: depth and distance
what are the subcortical structures of the brain?
the hippocampus and basal ganglia
where is the hippocampus and what is its function?
- deep in the temporal lobe
- learning, memory formation and retrieval regulation of the HPA axis
- if damaged, can cause antergrade or retrograde amnesia
what is the basal ganglia, what is their function and where is it located?
- they are neural structures embedded deep within the cerebral hemisphere
- there are 3 types: caudate, putamen and globes pallidus
- they initiate and maintain movement
-if damaged can lead to diseases like Huntington’s and parkinsons
what are gyri and sulci?
- gyri are bumps on the brain
- sulci are the grooves
- if the grooves are particularly deep, they are called fissures
what are the main sulci?
- central sulcus
- precentral sulcus: responsible for somatic sensations and touch
- post central sulcus: voluntary movement
what are some prominent fissures?
the lateral Sylvian fissure has the superior temporal gyrus responsible for audition
what is the diencephalon?
the division of the forebrain situated between the cerebral and mid brain
-consists of the thalamus and hypothalamus
what is the thalamus and what is it’s function?
- large collection of neutrons located in the dorsal part of the diencephalon
- relay between sensory and motor systems and cerebral cortex
- regulate arousal and pain, mood, motivation, cognitive functions
-synaesthesia: merging of the senses
what is the the hypothalamus and it’s function?
- small collection of neurones located directly above the brain stem
- has homeostatic and reproductive functions
- responsible for fight or flight response
-diseasesL hyperthyroidism, hypothyroidism
what are the 3 regions of the brain stem?
midbrain, pons, medulla oblongata
what is the function of the midbrain?
controls eye movements, auditory and visual processing
what is the function of the pons?
relay of motor neurone from cerebral hemisphere to medulla, spinal cord and cerebellum
what is the function of the medulla oblongata?
- cardiovascular and repiratory homeostasis
- reflexive actions
what does it mean if you are braindead?
inability to regain consciousness or breath w/o the support of an artificial life support machine
-loss of blood circulation to all brainstem regions
what is locked-in syndrome?
- awake and conscious but with no means of producing speech or movement
- loss of blood circulation to pons
what is the cerebellum?
the prominent hindbrain and accounts to 10% of brain mass
what is the function fo the cerebellum?
-does not initiate movement but detects differences in ‘motor error’ between an intended movement and actual movement
-aids motor cortex to produce and coordinate a movement
-importnat in synchronisation of movement w musical rhythm
= highly conserved across animal kingdom
how is the spinal cord structured?
- cervical vertebrae: loacted in the neck (C1-C7)
- thoracic vertebrae: attached to the ribs (T1-T12)
- lumbar vertebrae: located in lower back (L1-L5)
- sacral vertebrae: ;platted within pelvic area (S1-S5)
how do spinal nerves communicate w SC?
via notches between vertebrae
how is the vertebral notches split?
into 2 notches: dorsal and ventral
describe the dorsal root
bundle of sensory neuron axons that carry sensory info into the SC
describe the ventral root
bundle of motor neurone that carry info away from the SC to striated muscle
how is the SC organised?
- by white matter: composition of axon bundle divided into columns
- by grey matter: composition of neuronal cell bodies divided into horns
what is the function of the SC
- contains motor neurone that innervate SKM and allow movement
- contains motor tracts that carry information for motor movement
- recieves sensory info from periphery of the body
- contains pathways where info is transmitted to the brain
what are motor neurone pools to the skeletal muscle influenced by?
by the descending systems: motor cortex and brainstem centres
what does the motor cortex do?
planning, initiating and directing voluntary movements controlled by basal ganglia
what does the brain stem centre do?
-ensures basic movement and postural control controlled by cerebellum
how is a reflex movement created?
sensory inputs to the local circuit neurones
what is tetraplegia?
full or partial loss of sensation and movement in all 4 limbs and torso caused by damage in cervical area (C1-C5)
what is paraplegia?
full or partial loss of sensation and movement in both legs (and torso- depending on location of lesion)
-causes by damage in thoracic (T1-T12), lumbar (L1-L5) or sacral (S1-S5) areas
how is the brain supported and protected?
- by the meninges
- the ventricular system of the brain
- the vasculature of the brain
what are the meninges?
-the 3 layers that cover the brain and SC
what are the 3 layers of the meninges and what are the main functions?
- the dura mater, the arachnoid membrane and Pia mater
- they protect the brain
what is the ventricular system?
the passage of cerebrospinal fluid (CSF) that fill the spaces that lie at core of the forebrain and brainstem
what is the ventricular system made of?
lateral ventricles, third ventricle and fourth ventricle
what is the function of the ventricular system?
- protection of the brain: acts as a cushion for physical shock
- regulation of buoyancy
what is the vasculature system?
2 pairs of arteries supplying blood to the brain:
- internal carotid arteries (anterior circulation): supplies to forebrain
- vertebral arteries (posterior circulation): supplies to brainstem, cerebellum, upper SC
what is the function of the vasculature system?
- O2 supply
- CO2 removal
- transport of nutrients and waste products
