1. BRAIN - MACHINE INTERFACE PRESENTED BY:- TUHIN DAS

2. What is Brain-Machine Interface? It is a collaboration in which a brain accepts and controls a mechanical device as a natural part of its representation of the body By reading signals from an array of neurons and using computer chips and programs to translate the signals into action, scientists hope it will be possible for a person suffering from paralysis to control a motorized wheelchair or a prosthetic limb by just thinking about it

3. Concept of brain gate The BrainGate system is a neuromotor prosthetic device consisting of an array of one hundred silicon microelectrodes, each of which is 1mm long and thinner than a human hair. The electrodes are arranged less than half a millimetre apart on the array, which is attached to a 13cm-long cable ribbon cable connecting it to a computer

4. Biological inspiration Dendrites Soma (cell body) Axon

5. Biological inspiration dendrites axon synapses The information transmission happens at the synapses.

6. Artificial neurons Neurons work by processing information. They receive and provide information in form of spikes. x1 x2 x3 … xn-1 xn w1 Output w2 Inputs y w3 . . . wn-1 wn The McCullogh-Pitts model

7. Artificial neurons Nonlinear generalization of the McCullogh-Pitts neuron: y is the neuron’s output, x is the vector of inputs, and w is the vector of synaptic weights. Examples: sigmoidal neuron Gaussian neuron

8. Neural network mathematics Neural network: input / output transformation W is the matrix of all weight vectors.

9. Cortical neural signal extraction: non-invasive vs. invasive recording EEG Rhythms β and μ, P300, Slow cortical potential (SCP) Sampling rate 200-1000Hz, # of channels, from 1 or 2 to 128 or 256 Electrodes Bioactive, allowing growth of nerve, or bio-inactive multiple mircowires or multichannel electrode arrays Superficial motor areas or deep brain structures Primary motor, parietal, premotor, frontoparietal, basal ganglia

10. HOMONCULUS: The littleguy

11. Cortical neural signal extraction: ECoG resting imagining saying the word ‘move’ (d) Imagery is associated with decrease in µ (8–12 Hz) and β (18–26 Hz) bands. A brain–computer interface using electrocorticographic signals in humans*Leuthardt et al 2004 J. Neural Eng. 1 63-71

12. CONTROLLING OF MACHINE :- BY HUMAN BRAIN

13. The Brain-Controlled Vehicle Signal Processing Algorithms/Command Extraction Neural Interface Neural Signals Directional control Control Command Vehicle State Signal Environmental Feedback Vehicle Sensors

14. Application It can help to restore any loss of senses 1.sense of vision 2.sense of hearing 3.sense of movement creation of human robots Creation of detective rats

15. Biggest reward On 7th november 2009 toyota launched it’s wheel chair that works on thought It has a reaction time of 123 milliseconds

16. THANK YOU…..