Transcript Brain Scanning Technology

Brain Scanning Technology
BLOA

How do we know what’s going on
inside the brain?
 What
do these
techniques involve?
 Ablation
 Lesioning

Ablation – removing part of the brain

Lesion – scarring or damage (either intentionally as
part of an operation, or due to accidental brain
damage
Fat Rats
How
do we know
when to stop
eating?
Hetherington and Ranson
(1942)

Hetherington and Ranson (1942)

Experimented using rats

Lesioned the ventromedial hypothalamus

Rats ate far more than usual

Researchers believed this proved that the hypothalamus stops us from
eating too much.

More recent research suggests that we still do not fully understand the
role of the hypothalamus (though it is involved in the regulation of
hunger)
What
alternatives do we
have now to lesioning and
ablation?
One

technique is the EEG
Show Brain Story
Electroencephalogram
(EEG)

EEG
EEG
EEG

Watch
EEG
EEG
PET

A PET scan monitors glucose metabolism in the brain

Patient given radioactive glucose

PET detects radioactive particles

Produces coloured maps of brain activity

Can detect abnormalities like tumours

Used in Alzheimers research

Can compare differences in normal and abnormal brains
Positron Emission
Topography (PET)
PET
PET
PET

Gur et al (1995)
functional magnetic
resonance imaging (fMRI)

fMRI uses magnetic fields and radiowaves

Shows actual brain activity

Higher resolution than PET
fMRI