PSYC 301 Final - New Frontiers 3

Brain Computer Interfaces

Brain Computer Interfaces

AI with the brain that bypasses natural mechanisms for output (speech, typing, gesturing...) and/or input (vision, hearing, touch...)

• Provides feedback

What are the elements of BCIs?

1. Record brain activity

2. Process

   • Via computer, identify the user’s desired action

3. Control 

   • Signal sent to application to carry out desired command 

4. Feedback

   • Indicates to user that action was successful 

What are the three types of sensors used in BCI?

1. Non-invasive (weakest signal, dispersed by bone/skin/hair)

2. Semi-invasive

3. Invasive (requires contact with brain, surgical opening of skull)

Non-Invasive Recording

• EEG 

• fNRS 

• fMRI

Semi-invasive recording

• Electrocorticography (ECoG) electrodes placed outside dura mater (epidural) or under dura mater (subdural) 

• Only performed as part of medically necessary procedures

Invasive Recording

Cortical implants are the only well-established invasive recording sensor

• Utah Array

  • First + most studied. Approved implantable sensor

In development:

• Neuropixels

  • multi-electrode array

  • can record from hundreds of neurons simultaneously

• Stentrodes

  • Wire and electrode threaded into brain’s blood vessels through other part of body

  • can only record parts of brain near blood vessels

• Neural Lace

  • Many flexible proves inserted via surgical robot

What are the anticipated outputs of these invasive recording sensors?

• Control a myoelectric prosthesis 

• Control an assistive device 

• Controlling a speech synthesizer

Explain myoelectric prosthesis

Bidirectional BCI. Prosthetic limb controlled by electrical signals from the user's muscles

• Use surface electrodes to detect and amplify the electrical activity of muscle groups

• translate signals into movement of the prosthetic limb

• Electrodes implanted in motor and somatosensory cortices 

• Stimulating somatosensory cortex as through hand is being touched 

  • Improves task performance 

Deep Brain Stimulation (DBS)

• Two intracranial electrodes implanted into basal ganglia, thalamus, or brain stem w/ implantable pulse generator (IPG) 

• Stimulates based on predetermined control policy 

WHat are the applications/potential applications of DBS?

Applications:

• Movement disorders (ex. Parkinson’s) 

Potential Applications:

• Alzheimer’s disease, OCD, Tourette syndrome, major depression disorders, addiction, anorexia, etc. 

Visual Implants

• Stimulating without recording!

• Retina/Occipital Lobe

• Not as detailed as typical vision, but can tell when the street ends, what room you’re in, etc.

Discuss some ethical concerns with BCIs

• Corporate accountability/end of use

  • ex. company stopping implant without notifying patients

  • Did not do anything to device after study (removal/maintenance)

• User safety

  • Sudden shut-down of implant for patients using it

  • Complications from implant (ex. scarring on brain)

  • Unknown interactions with brain plasticity

  • Unknown effects of removal

• User burden

  • Ex. choosing to prioritize implant use over taking medications bc medications interferes with implant effectiveness

• Autonomy

  • May produce incorrect/unwanted actions

  • May reveal inner thoughts

• Cyborgization/personhood

  • People feel implant is a tool rather than a part of them

• Judging Agency

  • Who is responsible for BCI outputs if it carries unintentional actions? Individual vs. tool