brain scanning technology bloa. how do we know what’s going on inside the brain?

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 RatsFat Rats

How do we know when to stop eating?

Hetherington and Hetherington and Ranson (1942)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 Electroencephalogram (EEG)(EEG)

EEG

EEGEEG

EEGEEG Watch

EEGEEG

EEGEEG

PETPET 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 Positron Emission Topography (PET)Topography (PET)

PETPET

PETPET

PETPET Gur et al (1995)

functional magnetic functional magnetic resonance imaging resonance imaging

(fMRI)(fMRI) fMRI uses magnetic fields and radiowaves

Shows actual brain activity

Higher resolution than PET

fMRIfMRI