Presentation is loading. Please wait.

Presentation is loading. Please wait.

Brain imaging techniques PET Mikrolesions Single cell Lesions 2-Deoxyglucose Multi-unit Patch clamp EEG & MEG TMS fMRI Optical Imaging millisecundum sec.

Similar presentations


Presentation on theme: "Brain imaging techniques PET Mikrolesions Single cell Lesions 2-Deoxyglucose Multi-unit Patch clamp EEG & MEG TMS fMRI Optical Imaging millisecundum sec."— Presentation transcript:

1 Brain imaging techniques PET Mikrolesions Single cell Lesions 2-Deoxyglucose Multi-unit Patch clamp EEG & MEG TMS fMRI Optical Imaging millisecundum sec min hour day year Log time (sec) Lamina Neuron Dendrite Synapse Lo g Re sol uti on (m m) Brain Column

2 Patch-clamp recordings: a single channel

3 Patch-clamp recording techniques

4 Even parallel dendritic and somatic patches are possible

5 A typical result: the I-V curve

6 Electric activity of the brain on different scales

7 Lengyel Máté: Egysejt modellek II / Modellek az idegrendszer-kutatásban - ELTE TTK, 2003 tavaszi félév 77 Discovery of the electricity in animals: 1792 Galvani, De Viribus - Electricitatis in Motu Musculari.

8 Lengyel Máté: Egysejt modellek II / Modellek az idegrendszer-kutatásban - ELTE TTK, 2003 tavaszi félév 88 Discovery of the electroencephalography (EEG) Hans Berger The first EEG record The alpha rythm Electric signs of epilepsy Investigated the telepathy

9 Elektroencephalography (EEG) and magnetoencephalography (MEG)

10 EC IC V dV ext ICIC IRIR R EC R IC I axial ICIC IRIR ICIC IRIR I ~ CSD I ~ CSD I ~ CSD The source of the EC potential is the sum of the capacitive and resistive currents The sum of I R is not zero, But the sum of I CSD is zero for the whole cell!

11 Multi Electrode Array Original current source density distribution Sink Source Zero T(d) The forward problem

12 Multi Electrode Array Original current source density distribution Sink Source Zero T(d) The forward problem

13 The origin of the EEG and MEG

14 Normal resting EEG

15 EEG imaging with dipole localization

16 Evoked potentials 20 µV 2 µV

17 The auditory evoked potential:

18 Extracellular recordings

19 Identification of excitatory and inhibitory connections by correlation requires parallel recording of hundreds of neurons.

20 Active feedback via electrodes

21 Positron emission tomography (PET)

22

23 PET-based functional brain imaging

24 The MRI machine

25

26

27 The BOLD response: the basis of the fMRI

28 High resolution functional brain imaging with fMRI

29 Mind-reading with fMRI Results: Learning on 1750 pictures Selection from 120 new pics: 92% Selection from 1000 new pics: 82%

30 Direction selective neurons in the motor cortex Both the motor and the somato-sensory cortex represents the whole body Each cell is tuned to a specific direction

31 Brain-machine interface in monkeys The direction and speed of the planed movement could be determined from the activity of the cells and their directional tuning.

32 BMI with invasive electrodes

33 BMI with non-invasiv electrodes

34 Arm prosthesis driven by the nerves It is more easy to decode the planed motion from the activity of the peripheral nerves.


Download ppt "Brain imaging techniques PET Mikrolesions Single cell Lesions 2-Deoxyglucose Multi-unit Patch clamp EEG & MEG TMS fMRI Optical Imaging millisecundum sec."

Similar presentations


Ads by Google