neuroanatomy 1 Flashcards
what is the nervous system divided into?
central nervous system
peripheral nervous system
what is the central nervous system (CNS) made up of?
brain
spinal cord
what is the peripheral nervous system (PNS) made up of?
- nerves
- connects all different organs to the central nervous system
- motor pathways
- sensory pathways
what do motor pathways involve?
sends information to muscles from nervous system
what do sensory pathways involve?
these bring information from sensory systems in to the central nervous system
Identify 3 main structures of the brain
- Cerebrum
- Cerebellum
- Brain Stem
Define contralateral
opposite side
i.e.: left side of brain control the contralateral side of body
Define Ipsilateral
same side
How much blood flow from heart goes to the brain?
20%
What is the anterior (rostral) part of the brain?
front of brain
What is the posterior (caudal) part of the brain?
back of the brain
What is the dorsal (superior) part of the brain?
top of the brain
What is the inferior (ventral) part of the brain?
bottom of the brain
define medial
towards the middle
define lateral
towards the side
define frontal/coronal plane
means parallel to your forehead
imagine slicing through brain parallel to forehead
define sagittal plane
means the side view
imagine slicing through the brain, through the nose
define horizontal plane
means the plane is parallel to the ground
what is grey matter made up of?
cell bodies and dendrites
identify parts of the brain that are made up of grey matter
cortex
basal ganglia
thalamus
what is white matter made up of?
myelinated axons
give an example of a white matter structure
corpus callosum
define commissure
a pathway that connects the right hemisphere and the left hemisphere
an example of this would be the corpus callosum
what is the corpus callosum?
the largest fiber bundle that connects the two hemispheres
200 million fibers
how is the brain and spinal protected
bone and tissue
what is the tissue called that protects the brain and spinal cord?
meninges
describe the three layers of the meninges
- dura mater
outer layer - arachnoid membrane
second layer - pia mater
layer that directly covers the brain
what is meningitis?
inflammation of the meninges
from viral or bacterial infection
what is cerebrospinal fluid?
clear liquid that fills subarachnoid space
what is subarachnoid space?
space between arachnoid membrane and pia mater
what is the function of cerebrospinal fluid?
- shock absorber
- buoyancy
important as brain is quite heavy
brain floats in layer of CSF
CSF reduces weight of brain
where does the CSF come from? Explain.
the ventricular system
produced by a membrane called choroid plexus by filtering blood
what is the ventricular system?
- these are cavities in the brain
- they are filled with CSF
- you have two lateral ventricles (one in each hemisphere)
- third ventricle
- fourth ventricle
what is the function of the ventricular system?
exchanging of materials between blood vessels and brain tissue
gaining nutrients from blood supply
removing waste products
identify another protection of the brain
blood-brain barrier
what is the blood-brain barrier?
- semi-permeable barrier
- does not have gaps that permit the free flow of substances into and out of the blood (like capillaries in the rest of the body)
- only lipid soluble substances can pass through
what is the purpose of the blood-brain barrier?
- maintain a stable environment in the brain
- protection from potentially disruptive/damaging chemicals
what is a problem with the blood-brain barrier?
if medicine is needed to get into the brain for treatment, blood-brain barrier stops medicine from getting in
outline features of the cerebral cortex
- 3mm thick
- folded to allow bigger SA:V ratio (more neuron in a smaller space)
- makes up 80% of brain mass
- only contains 19% of brain cells
- clefts/crack/grooves called sulci
- folds/bulges called gyri
identify the 4 lobes within the cerebral cortex
frontal lobe
parietal lobe
occipital lobe
temporal lobe
identify the names of major sulci and gyri
central sulcus
(goes down the centre of the brain)
precentral gyrus (fold/bulges before the central sulcus)
postcentral gyrus (fold/bulges after the central sulcus)
sylvian fissure/lateral fissure (the crack the separates the temporal lobe from the parietal and frontal lobe)
describe the frontal lobe
- anterior area of the cortex
- rostral to parietal lobe
- dorsal to temporal lobe
- divided from parietal lobe by central sulcus
- responsible for motor function and cognition
- decision making, planning, organising
describe the parietal lobe
- caudal to frontal lobe
- dorsal to temporal lobe
- responsible for somatosensory function
- related to the body and senses
describe the occipital lobe
- caudal to parietal lobe and temporal lobe
- responsible for vision function
describe the temporal lobe
- rostral to occipital lobe
- ventral to parietal lobe and frontal lobe
- responsible for hearing, vision, cognition and emotion
what is it meant by primary areas of the brain?
defined specific areas where cortex processes information from the senses
identify the primary areas in the brain
the following receive information from the senses:
primary somatosensory cortex
primary visual cortex
primary auditory cortex
the following are connected to muscle in the body:
primary motor cortex
all are contralateral
what are primary association areas?
the areas that do the processing and analysing of the information received from the primary areas