This document describes several techniques used to study the brain: 1. Electrical stimulation involves using electrodes to deliver electric currents to specific brain areas to stimulate them and observe behavioral responses, helping identify brain regions' functions. However, it is highly invasive. 2. Transcranial magnetic stimulation uses magnetic pulses through the skull to stimulate neurons near the surface, allowing non-invasive study of brain region functions. Long term effects are unclear. 3. Imaging techniques like CT scans, MRI, fMRI, PET scans provide information about brain structure and activity with varying levels of detail and invasiveness.

1. Take a look inside!

2. Electrical S+mula+on ‐ ESB
 Involves using an electrode to deliver a
precisely regulated electric current to
the brain, thereby stimulating a
specific area of the brain
 If electrical stimulation of a specific
brain area initiates a behavioural
response, then that specific area of the brain controls
or is involved in that response
 Extremely invasive – usually only conducted when
other surgery is already necessary

3. Transcranial Magne+c S+mula+on TMS
 Delivers a magnetic field pulse through the skull
stimulating the neurons closest to the point of entry
 Only effects neurons to a depth of
2 – 3 centimeters
 Good for establishing how
different brain regions control
different functions
 Long term effects of repeated
exposure are unclear
 Side effects can include localised
pain or headache

4. Computerised axial tomography (CAT) Scan
 A computer enhanced X‐ray of a slice (cross‐section) of
the brain created from X‐rays taken from different angles.
 CT is extremely useful for identifying the precise location
and extent of damage to or abnormalities in various brain
structures or areas. A CT scan can reveal the effects of
strokes, tumors,
injuries and other brain
disorders
 It does not provide information
about the activity of the brain

5. POSITRON EMISSION TOMOGRAPHY (PET)
 Prior to the scan being taken, the person is given a sugar‐like
substance that contains a harmless radioactive element. When this
substance enters the bloodstream it travels to the brain. As particular
parts of the brain are activated, the substance emits radiation which is
detected the PET scanner.
 Great for examining brain function when performing different tasks
 As it involves radioactive element regular use is to be avoided

6. Single photon emission cpmputed
tomography (SPECT)
 Similar to PET
 Radioactive tracer lasts longer
 Not as detailed as PET
 Can be combined with CT images to increase
resolution
 Much cheaper than PET

7. Magne+c resonance imaging (MRI)
 MRI uses a similar technique to the CAT scan, but instead
of using an X‐ray, harmless radio frequencies are used to
vibrate atoms in the neurons of the brain
 The amount of vibration is detected and analysed by a
computer
 MRI can be used to detect and display
extremely small changes in the brain.
For example, MRI can more clearly
distinguish between brain cells that
are cancerous and those that are
noncancerous.
 shows only brain structure not function

8. Func+onal magne+c resonance imaging (fMRI)
 The technique is based
on the standard MRI,
and measures subtle
changes in blood–
oxygen levels in the
functioning brain. When
an area of the brain is
active, there is increased
blood flow to that area,
as more oxygen is
required by the active,
functioning neurons

9. X‐RAY CAT

10. MRI

11. F‐MRI

12. PET

13. ESB