Methods of Research Flashcards
What can be used to measure structures in the brain?
Computerized Tomography (CT or “CAT”)
Magnetic Resonance Imaging (MRI)
Diffusion Tensor Imaging (DTI)
Strength of CT scans:
Cheap and easy; usually first scan given after injury.
Weakness of CT scans:
not very detailed pictures.
What is a MRI?
Uses an interaction between radio waves and a strong magnetic field to reproduce a picture of body tissue.
Strength of using an MRI?
High resolution pictures.
Can measure size of brain structures.
3-D representation from many angles.
What is DTI?
A type of MRI that measures movement of water through the brain
What is a DTI good for?
Great for reproducing a picture of white matter tracts.
Can measure thickness and how tightly packed the tracts are.
Gives you info about the quality of connections between brain regions.
Water in _________ tends to move faster and in straighter lines.
white matter
What are the 6 measuring functions of the brain?
- Ablation
- Transcranial Magnetic Stimulation (TMS)
- Microelectrodes
- Macroelectrodes – Electroencephalography (EEG)
- Functional MRI (fMRI)
- Positron Emission Tomography
What is ablation?
Disrupt brain functioning by removing part of the brain and measure behavior.
What is an example of ablation?
Split brain
What is a weakness of ablation?
You cannot do it experimentally on humans, only animals.
_______= Can measure effects in people who have had part of their brain damaged or removed for medical reasons.
Ablation
What is TMS (Trascranial Magnetic Stimulation)?
Disrupt brain functioning by stimulating neurons with electrical current from outside of the skull and measure behavior.
What are microelectrodes?
Records the activity of individual neurons from inside the brain.
Strengths of using microelectrodes?
measure exactly what a neuron is doing.
Weakness of using microelectrodes?
Invasive
Give an example of a macroelectrode:
EEG
What does an EEG do?
Record electrical activity of groups of neurons (inside or outside of the brain). (Thousands or millions of neurons).
Weakness of an EEG:
can’t localize which part of the brain the signal came from aka bad spatial resolution.
Strength of EEG:
Records very quickly (milliseconds) aka good temporal resolution.
What does a functional MRI (fMRI) do?
Measures the amount of oxygenated blood in your brain.
Why is a fMRI important?
More oxygen is very closely related to more neuronal activity
Strengths of fMRI:
can localize where the changes in oxygenated blood flow (aka neuronal activity) happened aka good spatial resolution
Can measure the entire brain.
