different techniques for studying brain function **
- histology
- autoradiography
- immunohistochemistry
- fluorescence
- tract tracing
- CT & MRI
- DTI
- lesions
- optogenetics
- EEG
- fMRI
- PET
how immunohistochemistry works **
- method use to look at brain tissue in the microscope
- localizes proteins (peptides) and enzymes neurotransmitter
- injects a chemical (antibodies) that bind to a specific protein and then when observed it shows only that specific neurotransmitter by coloring it
what histological methods are used for **
- the methods of fixing, slicing, staining, and examining the brain
- to identify nuclear masses in the brain
different human friendly imaging techniques **
-CT scanner: quickly, identify bone fractures, implants allowed
- PET and EEG
- MRI scanner: avoid radiation, more anatomical detail of brain
- DTI
- TMS
- Lesions
what fMRI measures and if fMRI measures action potentials **
- measures changes in blood oxygenation that can result from activity
- shows how networks of brain structures respond to various stimuli or while performing specific tasks
Optogenetics **
- use of a genetically modified virus to target expression of specialized ion channels in specific brain regions
- allows to turn neurons on and off ; depolarize or hyper polarize neurons using controlled bursts of light
- can help manipulate things that are very small
DREADDs **
-Protein engineering was used to altered g-protein coupled receptors to accept or bind to a designer drug
- able to manipulate large areas
- can send patient home, without any medical equipment attached
Anterograde tracing **
-away from soma, toward the axon terminals
retrograde tracing **
- to soma, from axon terminals
- tells where the soma is for the terminal buttons injected
afferent **
-arrives
efferent **
-exits
autoradiography
locates radioactive substance in a slice of tissue
-radioactive ligands bid to receptor proteins
CT
detects differences in structure or tissue type, such as tumors or bleeding
-limitation: low resolution images
MRI
- higher resolution images
- uses magnets and radio waves to determine tissue density in the brain
-Limitation: cannot assess activity
DTI
-measures diffusion (where water moves in the brain)
EEG
- measures the changes in summed electrical activity of many neurons
- gets a blurry pic
PET
- measures brain activity
- uses radioactive chemicals injected into the bloodstream and maps their destination
techniques not appropriate for studying brains of healthy college students **
- optogenetics
- electron microscopy
