who discovered that nervous activity has electrical basis and what year
neurons electrical activity is recroded called ______
what is the purpose of electro enectroencephalogram
show electrical activity caused by nerve cells firing. they recorded brain waves which reflect speed of firing in different states of mind
how are electroencapholgram used
electrode attached to skull
electrode connected to magnets which connected to pens
record electrical activity in brain
what are imaging mathods that are structural^diagnostic
how is computeruzed tomography (ct scan) used
xray beams passed through brain at different angles
it is good at identifying structures
how is positron emission tomography used (PET)
radioactive molecules injected into bloodstream or inhaled and detected by PET cameras
show areas of high and low blood flow in brain
high levels indicate high level of cognitive processing
explain scan subtraction method
determine average neural response to cognitive task
scan person at rest and then scan person doing cognitive task. take neutral and cognitive signal.
what is magnetic resonance imaging (MRI)-functional MRI
use large magnet and radio frequency pulse to generate brain signal that produces image
different curves for protons in oxygenated and unoxygenated blood provides functional image
neurons more actve=more oxygen used
FMRI patient scanned while performing cognitive task
who determined speed of electrical conduction and what date?
who invented the first EEG (electroencephalogram)?
what does it do?
patern of electrical activity in brain
when was PET and MRI/fMRI method of imaging discovered?
what does PET measure?
glucose absorption caused by increase in mental activity
what does MRI/fMRI and MEG measure?
heightened blood flow/ oxygen using re alignment of magnetic fields
frontal polar cortex
forward planning and control other brain regions
what are color codes of cerebrum, cortex, cerebellum and brainstem?
what is function of amgydala?
control of emotion
what is the function of hippocampus?
memory formation; spatial navigation
fine motor control and timing of movements
balance and stability
primary visual cortex
signal arrives from eyes via thalamus
what is diffusion tension imaging?
type of MRI that measure water flow among neurons
identify neural network of brain
what is magnetocephalography (MEG)?
superconducting coils detect brains magentic field
acurately pin points sources in primary auditory; somatosensory and motor areas
asist in clarification of functional organization of primary somatosensory cortex
what is trancranial magnetic stimulation (TMS)?
coil is activated over cortical area of brain and disturbs normal electrical acivity
used to identify areas of brain used to produce movement and motor learning studies
pertubation of motor area prevent learning of certain types of motor skills
what are advantages of imaging methods?
display changes in neural activity throughout brain
high spatial resolution (2-4mm)
what are disadvantages of imaging methods?
poor temporal resolution (3-4 sec to get image)
difficult to endure- noisy- closterphobic
difficult to analyze data
methods of imaging the brain