Neuroscience Methods Flashcards
1
Q
Golgi Stain
A
- neuron level
- developed many years ago to be able to identify neurons, first time we could see what a neuron looks like
- Allowed us to know there is a cell body with processes involved, some will show axon and dendrites
- Limitation: cannot differentiate between two neurons. Physically you can see that some look different from others, but doesn’t go beyond that
2
Q
Brainbow
A
- neuron level
- inject fluorescent dyes into the brain, each will be picked up by a different kind of neuron
- Each dye has a specific protein detector in it, targeting a specific population of neurons
- Allowed us to see which neurons are neurobiologically like one another(similar NTs produced, receptor makeup same, etc) due to color coding
3
Q
C-fos
A
- genetic code (transcription factor) that gets turned on when a neuron is active
- For example, if you wanted to know which particular neurons are active during stress, the neurons that have c-fos show up in them are the ones that are active when rat was experiencing stress
4
Q
Tracers
A
- neuron level
- allow us to see where neurons go
- retrograde and anterograde tracers
5
Q
Anterograde tracer
A
- Answers: Where does x project to?
- Ex. inject tracer in VTA so cell bodies take it up and then transport it to wherever they go
6
Q
Retrograde tracer
A
- Answers question: where does x receive input from?
- Ex. inject tracer in the NAc so the terminals take it up, sending it back to the cell bodies
7
Q
X-ray CT
A
- for imaging living humans
- allows you to look structurally, can see if there is anything wrong
- used routinely in clinic to identify structural differences
8
Q
Magnetic Resonance Imaging (MRI)
A
- Allows you to look at structural changes/differences
- Uses a magnetic field to identify structures
- more fine details/better image quality than MRI
9
Q
Diffusion tensor imaging (DTI)
A
- allows you to look at blood vessels and measure the CSF and blood that is flowing around
- can specifically test blood vessel damage (hemmorage, strokes, etc.)
10
Q
Positron Emission Tomography
A
- Uses radioactive material and actually allows you to detect receptor changes in the brain
- How the D2 receptor study was done
11
Q
fMRI
A
- Gives a difference image: leftover difference between control image and test image.. is the activity driven by the stimulus (can be done with any kind of task)
- BOLD signal (blood oxygen level deficiency): when neurons become active, they use up oxygen in the surrounding area (from the blood)… then using the magnetic field you can measure the amount of oxygen present in the blood in specific brain areas
- hemoglobin is magnetically charged so it can be detected by a magnetic field
12
Q
How are ex-vivo studies completed?
A
- look at the brain tissue outside of the organism’s body, but the tissue/neurons are still alive
- brain is taken out of the skull and immersed in oxygenated artifical CSF to give the same environment as if it were still attached to the animal
- Now, we can look at specific neurons
13
Q
Ex-vivo electrophysiology
A
- recording pipette goes to cell body of a neuron, pressure is applied, and the membrane breaks but forms seal w/ the pipette (called patching)
- now, the internal solution (cytoplasm) of the cell gets sucked into the pipette
- This allows you to measure electrical deflections (changes), including: single ionotropic channel changes, EPSPs and IPSPs, and action potentials
14
Q
In-vivo electrophysiology
A
- recording from an animal while behaving (alive)
- set of electrodes implanted into animal brain, so the activity of the neurons can be measured
- can measure overall activity and action potentials
15
Q
EEG
A
- measures electrical activity in humans, but less precisely than in animals
- electrodes placed over skull to measure electrical activity in specific parts of the brain to get activity of that particular region
