mod 2 Flashcards
rostral
anterior
caudal
posterior
dorsal
superior
ventral
inferior
lateral
toward the side
medial
toward the midline
ipsilateral
on the same side
contralateral
on the opposite side
longitudinal fissure
separates the two hemispheres
lateral sulcus
separates the temporal lobe from the frontal and parietal
central sulcus
separates the frontal and parietal lobes
temporal lobe gyri
superior, middle and inferior
parietal lobe gyri
postcentral gyrus, superior and inferior parietal lobule
frontal lobe gyri
precentral gyrus, superior/middle/inferior frontal gyrus
what separates the superior parietal lobule from the inferior parietal lobule
intraparietal sulcus
main fibre tract connecting the two cerbra
corpus callosum
large structure attached to dorsal aspect of the brain stem
cerebellum
subcortical structures
thalamus, basal ganglia
brainstem
midbrain - pons - medulla
basal ganglia
caudate nucleus + lentiform nucleus (putamen + globus pallidus)
where are superior and inferior colliculi found
midbrain
make up of ventricular system
consists of interconnected cavities filled with CSF
divisions of ventricular system
2 x lateral, third and fourth
what separates the lateral from the third
interventricular foramen
what separates the third from the fourth
cerebral aqueduct
white matter
axons, myelin
grey matte
cell bodies
10% of brain cells
neurons
90% of brain cells
glial cells
myelin
fatty substance that surrounds and insulates nerve fibres
destruction of myelin causes
multiple sclerosis
fMRI
records changes related to metabolic activity in order to produce a functional view of the brain
how many neurons are thought to be involved in representation of a single image
two hundred million neurons
brain lesion analysis
comparing people with brain lesion in region of interest with people whose region is intact
EEG
records brains electrical activity
ERP
a signature of the electrical activity (recorded by EEG) occurring in brain in response to specific event
ERP considers electrical response for three events
latency, amplitude + polarity, scalp topography
ERP temporal and spatial resolution
spatial not accurate, temporal accurate
structural neuroimaging
CT, MRI, DTI
functional neuroimaging
PET and fMRI
uses x-ray technology to produce a series of brain images enabling the structure of the brain to be viewed
CT
produces brain images with higher resolution than CT
MRI
provides view of white matter tracts using MRI scanner
Diffusion tensor imaging
provides image of concentration/distribution of the radioactive substance
PET
which has greater spatial resolution fMRI or PET
fMRI
records changes related to metabolic activity in successive images in order to produce functional view of brain
fMRI
non-invasive method that causes transient disruption of brain activity by emitting a brief magnetic pulse.
Transcranial magnetic stimulation TMS
TMS excitatory or inhbitory
can be either
a prominent fold of cartilage-supported skin, captures sound and focuses it into the auditory canal
pinna
where does auditory canal end
eardrum
outer ear components
pinna and auditory canal
outer ear
sound waves are captured by pinna and focused into auditory canal
middle ear components
ear drum (tympanic membrane) and ossicles
ossicles
incus, stapes, malleus
high pressure region does what to ear drum
pushes it inward
low pressure region does what to eardrum
pushes it outward
how are vibrations caused within ear
constant low and high pressure pushing eardrum in and out
vibrations travel from eardrum to ossicles to
cochlea
cochlea
spiral shaped fluid filled tube
where are hair cells
cochlea
what converts the sound signal to mechanical vibrations
the ossicles from the vibrations
what converts the mechanical signal to an electrical signal
hair cells
where do hair cells synapse
spiral ganglion cells
tinnitus
person hears noises in absence of any sound stimulus
how is tinnitus caused
by disease processes affecting cochlea or auditory nerve or spontaneous activity
inner ear to CNS
spiral ganglion cells –> vestibular nerve - vestibulocochlear nerve.
vestibulocochlear nerve
carries both balance (vestibular nerve) and hearing (auditory nerve) from cochlea to brain stem
auditory signal synapse where in brainstem
cochlea nuclei located at level of lower pons and upper medulla
auditory information from cochlear nuclei to where?
inferior colliculi to medial geniculate nucleus of thalamus to primary auditory cortex
auditory pathway in brain
cochlear nuclei - inferior colliculi - medial geniculate nucleus - primary auditory cortex
where is primary auditory cortex located
superior temporal lobe
hechls gyri
primary auditory cortex
tonotopic organisation
in primary auditory cortex
interaural time
difference in arrival time of sound at the ear
where is sound localisation not good
vertical plane
what produces the reflections of entering sound
bumps and ridges on outer ear
sound waves are captured by the pinna and focused into the auditory canal
external ear
sound waves strike the ear drum and the vibrations pass through the ossicles to the cochlea
middle ear
hair cells within the cochlea transduce the vibrations into a neural signal, which is sent to spiral ganglion cells, whose axons form the cochlear nerve which carries info to brain stem via vestibulocochlear nerve
inner ear
where is medial geniculate nucleus found
thalamus
the opening that allows light to enter the eye and reach the retina
pupil
a circular muscle that controls the size of the pupil
iris
the transparent surface that covers the pupil and iris
cornea
the white of the eye, continuous with cornea
sclera
helps focus ray of light on the retina
lens
the internal lining of the rear two-thirds of the eye; converts images into electrical impulses, which are sent to the brain
retina
the central area of the retina that is specialised for the central vision
macula
marks the centre of the retina and the centre of the macula
fovea
visual image is the least distorted
fovea
made up of the axons of retinal ganglion cells, carries impulses for vision from the retina toward the brain
optic nerve
wavelength of electromagnetic energy that is visible to the naked human eye
400-700nm
flow of information within the retina
photoreceptors -> bipolar cells -> ganglion cells