Brain Computer Interface

Outlines What is BCI? How does it work? Brain Wave Control Simple introduction of the brain Data Acquisition Apps Drawbacks & Future Q&A

What is BCI?

Brain -Computer Interface - Direct Neural Interface or Brain-Machine Interface Direct communication pathway between a brain and an external device. Research on BCIs began in the 1970s at the University of California Los Angeles

How does it work? Signal Acquisition Signal Processing Devices

Brain Wave Control

Active ◦ α (8 – 12 Hz): relaxed/reflecting ◦ β (12 – 30 Hz): alert/working - Training - Misjudgment

Brain Wave Control Passive ◦ Evoked potentials

Brain Wave Control Passive ◦ Evoked potentials

Brain Wave Control Passive ◦ Evoked potentials

Simple introduction of the brain Focus on cortex

Cerebral cortex Cerebellum Midbrain

Structure of the cortex

Cortex

Primary Somatosensory Cortex Primary Motor Cortex Motor Association Cortex

Sensory Association Area Visual Association Area Visual Cortex Wernicke's Area

Prefrontal Cortex Speech Center (Broca‘s Area) Auditory Cortex Auditory Association Area

Data Acquisition

Invasive BCIs Non-Invasive BCIs Partially-Invasive BCIs Wireless BCIs

Invasive BCIs Implanted: grey matter Signals: highest quality Scar-tissue build-up Target: ◦ repairing damaged sight ◦ providing new functionality to persons with paralysis  Artificial Vision System

Electrode Arrays

App.- Artificial Vision 4X4 16 pixels 8X8 64 pixels 12X pixels 16X pixels 32X pixels 128X pixels

Non-Invasive BCIs poor signal resolution power muscle implants and restore partial movement Interfaces ◦ EEG ◦ MEG ◦ MRI

MEG Magnetoencephalography Magnetic Field: T ~ T (Weak!!) ◦ S.Q.U.I.D. Sensors ◦ Shielded Room

Magnetic Field

Partially-Invasive BCIs Implanted: skull lower risk of forming scar-tissue in the brain Signal quality between invasive BCIs & non-invasive BCIs

Wireless BCIs More practical Embedding multiple chips ◦ More complicated thoughts Transmission with RF key requirement: keep the heat down

Wireless BCIs Size: 2cm in diameter 、 8cm thick Low cost Receive Distance: 10m ~ 50m

Examples of BCI

Rats implanted with BCIs in Theodore Berger’s experiments

Monkey operating a robotic arm with BCIs

arrangments P300->300ms

Disadvantages Headache Exhausting Laziness Degenerate

Future Integrate with different territory From lab to factory Nursing and medical treatment

Q&A