Bionics 3

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Bionics 3

• Kevin Warwick
• www.kevinwarwick.com
• http//en.wikipedia.org/wiki/Kevin_Warwick

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Animals Experiments

• Animal testing/experiments can be questioned from
  an ethical viewpoint
• Interested here more in neural aspects
• Not chemical
• Not external
• Behavioural?
• Humans are animals!

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Pavlovs Dogs

• Pavlov performed experiments on digestion which
  earned him the 1904 Nobel Prize. These included
  surgically extracting portions of the digestive
  system from animals, severing nerve bundles to
  determine the effects, and implanting valves
  between digestive organs and an external pouch to
  examine the organ's contents.

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Pavlovs Dogs

• Research on reflex actions involved involuntary
  reactions to stress and pain. Pavlov began the
  study of transmarginal inhibition (TMI), the
  body's natural response of shutting down when
  exposed to overwhelming stress or pain. His
  research showed that all temperament types
  responded to the stimuli the same way, but
  different temperaments move through the responses
  at different times. He felt this was due to a
  different type of nervous system.

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Pavlovs Dogs

• It is popularly believed that Pavlov always
  signalled the occurrence of food by ringing a
  bell. However, his writings record the use of a
  wide variety of stimuli, including whistles,
  tuning forks and visual stimuli, in addition to
  ringing a bell.
• Carl Jung continued Pavlov's work on TMI and
  correlated the observed shutdown types in animals
  with his own introverted and extroverted
  temperament types in humans. Introverted persons,
  he believed, were more sensitive to stimuli and
  reached a TMI state earlier.
• William Sargent continued the behavioural
  research in mental conditioning to achieve memory
  implantation and brainwashing.

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José Delgado

• Delgado used what he called a stimoceiver, a
  radio which joined a stimulator of brain waves
  with a receiver which monitored EEG waves and
  sent them back on separate radio channels.
• He said that Radio Stimulation of different
  points in the amygdala and hippocampus produces a
  variety of effects, including pleasant
  sensations, elation, deep, thoughtful
  concentration, odd feelings, super relaxation,
  coloured visions, and other responses.

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José Delgado

• Once Delgado stepped into the ring with a bull
  which had had a stimoceiver implanted. The bull
  charged Delgado, who pressed a remote control
  button which caused the bull to stop. Delgado
  claimed that the stimulus caused the bull to lose
  its aggressive instinct.
• Delgado believed that his experiment with a
  female chimpanzee named Paddy was more
  significant. Paddy was fitted with a stimoceiver
  that detected a brain signal called a spindle.
  When a spindle was detected, the stimoceiver
  responded with a signal to the central gray area
  of Paddy's brain, producing an 'aversive
  reaction'. Within hours her brain was producing
  many fewer spindles.

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Cockroach Backpack

• At the University of Tokyo electrodes were
  inserted into the antennae of a cockroach
  signals were sent to cause the cockroach to go
  forwards/backwards, left/right.

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Lamprey

• At Northwestern University, Mussa-Ivaldi built a
  two-wheeled robot that operated on the electrical
  signals of a lampreys brain. The part of the
  brain used in the experiment normally keeps the
  lamprey upright in the water. When connected up
  correctly, the organ can guide the robot towards
  a light source.

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Miguel Nicolelis

• Miguel Nicolelis at Duke University, North
  Carolina, wired a monkey brain to control a robot
  arm that mimicked the motions of its real arm.
  "It was an amazing sight to see the robot in my
  lab move, knowing that it was being driven by
  signals from a monkey brain at Duke," said
  Massachusetts Institute of Technology's
  Mandayam Srinivasan. "It was as if the monkey had
  a 600-mile- (950-km-) long virtual arm.
• KW comment no direct feedback (only visual).

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John Chapin

• Remote controlled rats! Movement signals are
  transmitted from a computer to the rat's brain
  via a radio receiver strapped to its back. One
  electrode stimulates the "feelgood" center of the
  rat's brain, while two other electrodes activate
  the cerebral regions which process signals from
  its left and right.

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John Chapin II

• In a separate experiment John implanted
  electrodes into the planning area in the brains
  of 6 rats.
• The rats were taught to push a lever to obtain a
  liquid treat.
• Signals were sent via the implant to cause the
  treat to be released without the need for the rat
  to actually push the lever.
• 4 out of 6 rats learned they didnt need to push
  the lever thinking about pushing it was fine.

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Brain Stimulation

• In 1870, two German researchers named Hitzig and
  Fritsch electrically stimulated the brains of
  dogs, demonstrating that certain portions of the
  brain were the centres of motor function.
• Bartholow, within four years, demonstrated that
  the same was true of human beings.
• By the turn of the twentieth century Krause was
  able to do a systematic electrical mapping of the
  human brain, using conscious patients undergoing
  brain surgery.

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Hess

• Hess, began his research into Electrical
  Stimulation of the Brain in the 1930s, jolting
  patients' brains with shocks administered through
  tiny needles that pierced the skull.
• His experiments included the insertion of fine
  electrically conductive wires into the brains of
  anaesthetized cats.
• Given mild electrical stimulation the cats went
  beserk.

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Penfield

• During the 1940s and 50s, Penfield experimented
  with electrical brain stimulation on human
  patients undergoing surgery.
• One of Penfield's discoveries was that the
  application on alert patients could stimulate the
  memory of past events.

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Pleasure??

• In 1956, Olds reported on research in which he
  had electrically stimulated the brains of rats.
• Implanting electrodes in rats' pleasure centre of
  the brain, he attached a button that allowed the
  rats to activate the electrical impulse
  themselves.
• The rats were able to choose between food and
  immediate pleasure.
• Olds found that the rats became so obsessed with
  self-stimulation that they would literally starve
  themselves to death.
• Later repeated with monkeys

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Monkeys

• Using high-tech brain scans on monkeys,
  researchers determined that a small clump of
  cells are active in the formation of the desire
  (plan) to carry out specific body movements.
• Armed with this knowledge, researchers at CALTECH
  implanted electrodes in the cortex of a rhesus
  monkey trained to play a simple video game.
• A computer program, hooked up to the implanted
  electrodes then moved a cursor on the computer
  screen in accordance with the monkey's desires -
  left or right, up or down.

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Tipu Aziz/Parkinson

• Tipus work involves inducing Parkinsonian
  symptoms in monkeys, either surgically or
  chemically, then switching off the symptoms using
  implanted electrodes.
• As many as 40,000 PD people around the world have
  benefitted from the technique.
• The technique, which Aziz pioneered in the UK,
  has been shown to alleviate symptoms in human
  sufferers of PD and dystonia.
• Patients have electrodes permanently implanted in
  their brains, wires are attached under the skin
  to a control chip, and a battery inserted into
  the chest.
• We will look at this in more depth later in the
  course

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Cultured Neural Network

• Culture brain cells directly on to a recording
  surface and re-embody the brain within a
  robotic body.

• Multi-Electrode Array (MEA) allows recording from
  128 electrodes across the entire culture.

200?m
TiN Electrodes 30?m diameter
Neurone
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Embodiment

• Re-embodiment is essential
• Without it the neurones are simply talking to
  themselves resulting in no meaningful input /
  output relationship.
• This can be demonstrated in animals that have
  developed in a sensory deprived environment the
  relative areas of the brain simply do not form
  the appropriate connections and the animal has
  limited functionality.
• Embodying the culture with a robot body means
  that its actions will result in specific sensory
  input which in turn should influence future
  decisions.

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Previous work
Animat (Potters group) Created a closed loop
system which successfully demonstrated approach
/ avoidance behaviour. Used a similar
system to fly a simulated plane. Angle of roll
mapped on to culture, plane stable in
strong simulated winds. T. B., Demarse, D. A.
Wagenaar, A. W. Blau and S. M. Potter, (2001).
The neurally controlled Animat biological
brains acting with simulated bodies. Autonomous
Robots no.11, pp.305310
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Methodology

• Culture to Robot Mapping
• How can the activity of the culture be mapped to
  the robots actuators and the robots sensors on
  to stimulate the culture.
• Biological Aspects
• The methods behind culturing maintaining and
  interfacing with neurones.
• Neural signal interpretation
• - Dimensionality reduction and processing before
  sending to robot.

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Culture Protocol

• MEAs coated with PDL (Poly-d-lysine) which allows
  neurones to adhere to the surface
• Primary cortical neurones enzymatically
  dissociated this breaks down the connective
  tissue before trituration which breaks off the
  axons and dendrites effectively leaving neural
  cells in a blank state.
• Dissociated cells are suspended in media and
  added to the MEA chamber.
• Cells are fed day 1 and every 4 days after with a
  glucose based media
• After a 1-2 days connections spontaneously reform
  and begin to resume activity, initially with
  single spikes and after roughly a week complex
  burst patterns are seen.

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Protocol Modifications

• Selective coating allows the neural density to be
  increased near the electrodes
• The use of younger animals may result in
  undifferentiated cells that are be able to adjust
  to be the most suitable cell type for the
  location they land in.

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Spike Sorting

• A single electrode may pick up signals from over
  100 neurones.
• It is essential to extract the useful signals
  from the noise and attempt to separate out the
  spikes from different neurones.
• Spikes that originate from different neurones
  have different voltage profiles (shapes)
  although this is not always true.
• Before transmitting this information to the robot
  - need to apply some form of dimensionality
  reduction, possibly involving Principal Component
  Analysis (PCA)

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3rd Generation (40 magnification)
200 ?m