methods table brain and behavior

CAT full name

Computerized Axial Tomography

CT scan full name

Computed Tomography

How does the CAT/CT work (uses)?

Uses X-rays to create a 3D image

What does the CAT/CT measure/visualise?

In vivo 3D images of the brain; visualizes brain structure through tissue density

Applications of the CAT/CT

Quick visualization of neurological damage; looks at bones and organs; detects tumors and brain trauma

Is the CAT/CT structural or functional?

Structural (anatomical information only)

Spatial resolution of CAT/CT

High resolution, less than 1 mm

Temporal resolution of CAT/CT

Not functional; no temporal resolution

Is the CAT/CT direct or indirect?

Neither; purely anatomical

Advantages of CAT/CT

Fast scanning; widely available; high-quality images; good for bone fractures

Disadvantages of CAT/CT

Radiation exposure; poor gray/white matter distinction; no functional information

MRI full name

Magnetic Resonance Imaging

How does an MRI work (uses)?

Uses magnetic properties of atoms with strong magnetic fields and radio waves

What does an MRI measure/visualise?

Hydrogen proton distribution; maps gray matter, white matter, and ventricles

Applications of MRI

Mapping brain abnormalities; visualizing soft tissue; diagnosing disease or injury

Is an MRI structural or functional?

Structural

Spatial resolution of MRI

High resolution, less than 1 mm

Temporal resolution of MRI

Not functional

Is an MRI direct or indirect?

Neither; purely anatomical

Advantages of MRI

Non-invasive; better gray/white matter contrast than CT; high spatial resolution; no radiation

Disadvantages of MRI

Expensive; slow; loud and claustrophobic; cannot be used with metal implants

DTI full name

Diffusion Tensor Imaging

How does a DTI work (uses)?

Uses two pulses of an MRI scanner

What does a DTI measure/visualise?

Anisotropic diffusion of water in axon tracts; white matter connections

Applications of DTI

Mapping neural tracts; studying white matter lesions; assessing connectivity (e.g., autism)

Is a DTI structural or functional?

Structural

Spatial resolution of DTI

Moderate; millimeter range

Temporal resolution of DTI

Not functional

Is a DTI direct or indirect?

Neither; purely anatomical

Advantages of DTI

Provides information about brain connectivity

Disadvantages of DTI

Not functional; motion sensitive; complex analysis; expensive

EEG full name

Electroencephalography

How does an EEG work (uses)?

Electrodes on the scalp using conductive gel

What does an EEG measure/visualise?

Electrical activity from many cortical neurons

Applications of EEG

Diagnosing epilepsy, sleep disorders, coma, brain damage

Is an EEG structural or functional?

Functional

Spatial resolution of EEG

Poor; centimeters

Temporal resolution of EEG

Very high; milliseconds

Is an EEG direct or indirect?

Direct

Advantages of EEG

Non-invasive; inexpensive; easy to conduct; tolerant of movement

Disadvantages of EEG

Poor spatial localization; only cortical activity; signal distortion

ERP full name

Event Related Potential

How does an ERP work (uses)?

EEG electrodes measuring responses to specific events

What does an ERP measure/visualise?

Brain responses to tasks or stimuli

Applications of ERP

Studying sensory and cognitive processing

Is an ERP structural or functional?

Functional

Spatial resolution of ERP

Poor; centimeters

Temporal resolution of ERP

Very high; milliseconds

Is an ERP direct or indirect?

Direct

Advantages of ERP

Non-invasive; inexpensive; high temporal resolution

Disadvantages of ERP

Poor spatial resolution; many trials required; scalp distortion

ECoG full name

Electrocorticography

ECoG uses

Electrodes placed directly on cortical tissue (invasive)

What does ECoG measure/visualise?

Direct electrophysiological cortical activity

Applications of ECoG

Epilepsy and tumor surgery

Is an ECoG structural or functional?

Functional

Spatial resolution of ECoG

Better than EEG; centimeters

Temporal resolution of ECoG

Very high; milliseconds

Is ECoG direct or indirect?

Direct

Advantages of ECoG

Better localization than EEG; no scalp distortion

Disadvantages of ECoG

Invasive; limited brain coverage; expensive

MEG full name

Magnetoencephalography

How does MEG work (uses)?

Helmet with sensors detecting magnetic fields

What does MEG measure/visualise?

Magnetic fields from neuronal activity (mainly sulci)

Applications of MEG

Localizing seizures; tracking neural dynamics

Is MEG structural or functional?

Functional

Spatial resolution of MEG

Millimeter range

Temporal resolution of MEG

Very high; milliseconds

Is MEG direct or indirect?

Direct

Advantages of MEG

Better spatial resolution than EEG; no scalp distortion

Disadvantages of MEG

Very expensive; weak signals; cortex only; magnetic shielding needed

PET full name

Positron Emission Tomography

How does PET work (uses)?

Radioactive tracer and PET scanner

What does PET measure/visualise?

Glucose metabolism (indirect neural activity)

Applications of PET

Alzheimer’s disease; cancer detection; surgical planning

Is PET structural or functional?

Functional

Spatial resolution of PET

Moderate; millimeters

Temporal resolution of PET

Low; seconds

Is PET direct or indirect?

Indirect

Advantages of PET

Measures tissue function; accurate diagnosis

Disadvantages of PET

Radioactivity; poor temporal resolution; expensive; long procedure

fMRI full name

Functional Magnetic Resonance Imaging

How does fMRI work (uses)?

MRI measuring hemodynamic changes related to neural activity

What does fMRI measure/visualise?

Blood oxygenation (BOLD signal)

Applications of fMRI

Brain mapping; surgery planning; studying cognitive processes

Is fMRI structural or functional?

Functional

Spatial resolution of fMRI

Very high; less than 1 mm

Temporal resolution of fMRI

Low; seconds

Is fMRI direct or indirect?

Indirect

Advantages of fMRI

No radiation; high spatial resolution; deep brain imaging

Disadvantages of fMRI

Indirect measure; poor temporal resolution; sensitive to non-neural changes