Chapter 3: Neuroimaging Flashcards
Transcranial Magnetic Stimulation (MTS):
Turns off and on parts of the brain if choice with magnetic fields that induce action potentials in the brain, investigating how turning off a part of the brain influences a particular psychological function.
Neuroimaging:
Creating images of the living, healthy brain with advanced technology.
Functional brain imaging:
Provides information about the activity of the brain while people perform various kinds of cognitive motor tasks.
Structural brain imaging:
Provides imaging about the basic structure of the brain and allows clinicians or researchers to see abnormalities in brain structure.
Spatial resolution:
The crispiness of the image.
Temporal resolution:
Where something is happening in the brain.
Computerized axial tomography scan (CT scans)
A scanner rotates a device around a person’s head and takes a series of X-ray photographs from different angles. Then the computer program combines these images to provide a view from any angle.
Helps provide information about brain structure and can spot tumours and other kinds of damage.
Magnetic resonance imaging (MRI scans)
Persons lie in a large magnet, magnetic field, hydrogen atoms line up and then relax and they give off energy - MRI detects the energy - different frequencies for different tissues.
Reveals nothing about the function of the brain
Diffusion Tensor Imaging:
Type of MRI, same MRI scanner, different protocol, hydrogen atoms inside the axon, easier for them to move in a certain direction, allows to capture axons.
Human Connectome Project:
A network map of the connectivity in the healthy human brain. It is open data.
Positron Emission Tomography (PET):
Radioactivity, injected with a radioactive substance (that the brain needs), decays in the brain - releases positrons, and scanned, more positrons releasing at a certain part of the brain = more activity.
Good for task-related brain activity.
Nobody does it, it’s expensive.
Functional Magnetic Resonance (fMRI):
Magnetic fields, measures the magnetic properties of oxygenated blood, can see where the oxygen in the brain is going. More oxygen = more activity.
Best: good balance of temporal (secs) and spatial resolution.
Brain networks:
Sets of brain regions that are closely connected to each other.
Default network:
A group of interconnected regions in the frontal, temporal, and parietal lobes involved in internally focused activities, like daydreaming, mind wandering, imagining future events, and remembering past events.
Group of brain areas that turn off when the brain is busy and turns on when the brain is chilling.
Subtraction (or contrast) Design:
Can subtract specific brain activity to see more specific brain activities (to see what other parts are included in a function).
