CT - Imaging; Structural (uses X-rays)

PET - Imaging; Functional (uses radioactive substance)

MRI - Imaging; Structual (magnets, radiofrequencies)

fMRI - Imaging; Functional (stimulation; compared to control/unstimulated)

EEG - Recording; Functional (evoked potentials)

MEG - Functional (changes in magnetic fields)

Single Cell -

Brain Stimulation

Neuro Research Methods (immaging & recording)

Structural vs. Functional

Structual                       Functional

  MRI (Im.)                                      fMRI (Im.)
  CT (Im.)                                         PET (Im.)
  Histology (Rec.??)                            EEG (Rec.)

                                                               MEG (Rec.)

                                                               Single Cell (Rec.)

highlights cell bodies; don't see structure of entire cell

to look at overview of many cells simultaniously

Srtuctural Immaging Technique

X-Ray

kinda invasive b/c exposure to X-rays

Functional Imaging technique

shows brain activity by injecting radioactive glucose, so Invasive

Structural Imaging technique

higher respolution than CT scans

measures magnetism

MRI advantages CT and PET: images taken at any angle w/o movement of individual.

Functional imaging technique

shows activity of brain, but less invasive than PET

tracks blood flow

used for comparison

(have to compare 2 control state; ex: record when hand not being touched and agian when hand being touched)

In tracking brain activity, fMRI is considered superior in both spatial and temporal resolution to PET scans.

EEG, MEG, Single-Cell

Records evoked potentials

rake many single trials and average them together

Cells from deeper structures in the brain have little, if any, influence on the EEG. The bones and tissue separating the brain from the electrodes substantially reduce the signal reaching the electrodes.

helpful when person’s behavior does not provide a clear indication of whether a particular stimulus has been perceived.

records the brain’s magnetic activity

superimposed on MRI

advantage of recording magnetism rather than electrical activity -- no interference of the skull bones and other tissues separating the brain from the electrodes. these tissues block brain’s electrical activity from being recorded using EEG, but allow magnetism to pass through without reduction. Also, recordings of the magnetic fields  taken much faster than fMRI or PET scans, providing moment-by-moment picture of brain activity. MEG silent (unlike MRI's loud magnets).

quite invasive; only really used on animals or during brain surgery

Brain stimulation - artificially stimulate areas of brain & watch resulting behavioral changes

- animals of during brain surgery

- invasive

TMS - records function

- fairly non-invasive (temporary effects)