1. Human Neurobiology 217 Prof Stuart Bunt SMBUNT@ANHB.UWA.EDU.AU Professor Stuart Bunt 217

2. Human Neurobiology 217 Prof Stuart Bunt SMBUNT@ANHB.UWA.EDU.AU Traditional Anatomy Phrenology, the study of bumps on the skull. Measuring brain weights and size (still being done..see the fuss about Einstein’s brain). Little link between morphology and performance Neanderthal > Homo sapiens Hydrocephalic genius

3. Human Neurobiology 217 Prof Stuart Bunt SMBUNT@ANHB.UWA.EDU.AU Plane Film X-rays Not very good for showing soft tissues Can show bone erosion Large space filling masses may be picked up if they have largely differing X-ray absorption Bone of skull requires high energy for penetration

4. Human Neurobiology 217 Prof Stuart Bunt SMBUNT@ANHB.UWA.EDU.AU Contrast Media Myelogram CAT with media around cord

5. Human Neurobiology 217 Prof Stuart Bunt SMBUNT@ANHB.UWA.EDU.AU Ventriculogram Air is introduced into the ventricles via the lumbar cistern (in adults) Via the fontanelles in infants Patient placed on a tilting table, air fills ventricles Can detect “space filling” lesions. Causes severe headaches, same dangers as lumbar puncture.

6. Human Neurobiology 217 Prof Stuart Bunt SMBUNT@ANHB.UWA.EDU.AU Subtraction Angiography Radio opaque medium is introduced into the internal carotid artery or systemically. Iodine compounds can promote allergic reactions, any arterial invasion dangerous. Subtract X-ray before contrast medium from X- ray with contrast medium. Can pick up any abnormality of the blood vessels.

7. Human Neurobiology 217 Prof Stuart Bunt SMBUNT@ANHB.UWA.EDU.AU Direct Stimulation During operations surgeons may have to delimit crucial areas. Epilepsy often spreads from a temporal lobe focus The speech area on the planum temporale must be identified. Cortex stimulated in conscious patient

8. Human Neurobiology 217 Prof Stuart Bunt SMBUNT@ANHB.UWA.EDU.AU Direct Stimulation

9. Human Neurobiology 217 Prof Stuart Bunt SMBUNT@ANHB.UWA.EDU.AU Computerised Axial Tomography Many X-rays are taken around the head (or body) Matching detectors pick up absorbed signal Computer reconstructs a “slice” Axial slices can be reconstructed in to a 3D pictures

10. Human Neurobiology 217 Prof Stuart Bunt SMBUNT@ANHB.UWA.EDU.AU CAT method

11. Human Neurobiology 217 Prof Stuart Bunt SMBUNT@ANHB.UWA.EDU.AU CAT

12. Human Neurobiology 217 Prof Stuart Bunt SMBUNT@ANHB.UWA.EDU.AU Magnetic Resonance Imaging 1 An extremely powerful magnetic field is used to orientate the spin of atoms. A radio frequency pulse is used to cause some atoms to flip Energy given off tells a lot about the molecule the atom is in Can also be used to form images.

13. Human Neurobiology 217 Prof Stuart Bunt SMBUNT@ANHB.UWA.EDU.AU CAT vs MRI MRI (previously known as nuclear magnetic resonance or NMR) is expensive. The magnet is supercooled with liquid helium in a liquid nitrogen blanket. Exposures are slow No metal may enter the field (no pacemakers etc.)

14. Human Neurobiology 217 Prof Stuart Bunt SMBUNT@ANHB.UWA.EDU.AU Ultrasound Ultrasound produced by a piezoelectric crystal or array No harm? Local heating and cavitation? Doppler effect raises frequency as blood flows towards detector, lowers frequency in the opposite direction Can map blood flow speed Can detect vasospasm (a potentially lethal sequalae to a stroke)

15. Human Neurobiology 217 Prof Stuart Bunt SMBUNT@ANHB.UWA.EDU.AU Positron Emission Tomography Inject a very short lived (radioactive) isotope with extra proton into the internal carotid. Produced in an (adjacent) cyclotron Gives out a positron, leaving a neutron. Positron anhilated when it hits and electron. Produces two photons in opposite directions Simultaneity detectors record the event. Choice of labelled compound determines the result (transmitter etc.)

16. Human Neurobiology 217 Prof Stuart Bunt SMBUNT@ANHB.UWA.EDU.AU PET Cyclotron Detector Scanner

17. Human Neurobiology 217 Prof Stuart Bunt SMBUNT@ANHB.UWA.EDU.AU PET

18. Human Neurobiology 217 Prof Stuart Bunt SMBUNT@ANHB.UWA.EDU.AU fMRI By targeting protons in hydroxyl groups can measure blood flow Areas of high flow = areas of high activity. Usual advantages of MRI (see previous slide) No radioactivity needed, replacing PET

19. Human Neurobiology 217 Prof Stuart Bunt SMBUNT@ANHB.UWA.EDU.AU Deep Infrared New technique Involves use of far infrared to penetrate the skull Reflected light picked up Reflected better by areas of high blood flow Experimental, low resolution as yet.

20. Human Neurobiology 217 Prof Stuart Bunt SMBUNT@ANHB.UWA.EDU.AU SQUIDS Supercooled, quantum interference devices Can pick up minute magnetic fields created by the activity of cells. More localised than EEGs, not an “average” Low resolution as the detectors are large

21. Human Neurobiology 217 Prof Stuart Bunt SMBUNT@ANHB.UWA.EDU.AU ERPS

22. Human Neurobiology 217 Prof Stuart Bunt SMBUNT@ANHB.UWA.EDU.AU EEGs Extra cerebral recordings average all the electrical activity going on in the brain Widespread changes can be picked up (epilepsy, coma, REM sleep etc.)

23. Human Neurobiology 217 Prof Stuart Bunt SMBUNT@ANHB.UWA.EDU.AU Labelling

24. Human Neurobiology 217 Prof Stuart Bunt SMBUNT@ANHB.UWA.EDU.AU