Methods, Emerging Technologies, Neuroethics

Brain Imaging

Used to visualize the structure or function of the brain.

Computed Tomography (CT)

Radiation (x-rays) of the head taken from different directions.

Advantages of CT

Fast, structural images.

Disadvantages of CT

Exposure to radiation.

Application of CT

Clinical: Brain injury.

Magnetic Resonance Imaging (MRI)

Uses magnetic fields and radio waves to create images.

Advantages of MRI

No radiation exposure, more detail in soft tissue (brain).

Disadvantages of MRI

Slower, louder, confining, can't use with metal in body.

Applications of MRI

Clinical imaging of brain for many reasons; broad research use.

Functional Magnetic Resonance Imaging (fMRI)

Magnetic field detects changes in oxygenation of blood.

Increased neuron activity

Increased blood flow.

Advantages of fMRI

No shots, ingested substances, or radiation.

Disadvantages of fMRI

Poor temporal resolution.

Applications of fMRI

Research; clinical changes in blood flow (stroke).

Positron Emission Tomography (PET)

Measures emissions of radioactively labeled chemicals.

Advantages of PET

Can see glucose use in the whole brain/body at rest; ability to study brain physiology and chemistry.

Disadvantages of PET

Radiation exposure; injections; poor temporal resolution.

Applications of PET

Clinical: Measurement of brain activity or protein accumulation to diagnose disease; research in clinical trials.

Electroencephalography (EEG)

Detects waves of electrical activity in the brain.

Advantages of EEG

Simple, non-invasive, inexpensive; good temporal resolution.

Disadvantages of EEG

Poor spatial resolution; background noise.

Applications of EEG

Clinical: evaluate brain disorders- epilepsy, stroke, tumor, narcolepsy; research: broad uses.

Transcranial Magnetic Stimulation (TMS)

Magnetic field is used to excite neurons.

Advantages of TMS

Non-invasive, relatively safe.

Disadvantages of TMS

Some risk of side effects.

Neuropathology

Study of brain tissue to diagnose disease.

Brain-to-brain communication

A method of communication where one brain's activity is recorded and another brain is stimulated.

Chronic Traumatic Encephalopathy (CTE)

A neurodegenerative disease associated with the accumulation of tau protein.

Brain-Machine Interfaces

Technologies that enable direct communication between the brain and external devices.

Sender in Brain-Machine Interfaces

The brain activity recorded with EEG.

Receiver in Brain-Machine Interfaces

The brain that is stimulated with TMS.

Neuralink

A company focused on developing implantable brain electrodes.

CRISPR

Clustered Regularly Interspaced Short Palindromic Repeats

DNA cutting system

Guide RNA (gRNA) recognizes a sequence of DNA and a protein (Cas9) breaks the DNA

Cell can repair the DNA (usually makes mistakes that mutate the gene) or donor DNA can be provided to fill in the broken spot

Being used to develop “gene therapies”  for genetic diseases and cancer therapies

Cognitive Enhancers

Chemicals or devices that improve cognitive ability.

Prescription drugs for cognitive enhancement

Examples include Amphetamine (Adderall), methylphenidate (Ritalin), and Modafinil (Provigil).

Transcranial direct current stimulation (tDCS)

A brain stimulation technique that uses electrical currents to modulate neuronal activity.

Neuroscience Research in Animals

Research conducted on animals to understand human brain mechanisms.

Editing Germline DNA

Making genetic changes that are heritable by editing a 1 cell embryo.

Potential diseases curable by germline editing

Huntington's Disease, early-onset Alzheimer's, Muscular Dystrophy, and Cystic Fibrosis.

fMRI Imaging as a Lie Detector

Studies that observe differences in brain activation during truth and deception.

BRAIN Initiative

A mission to map and measure the brain's circuits and explore ethical implications of new technology (Brain Research Through Advancing Innovative Neurotechnolgies)

Neuroethics

The study of ethical issues arising from neuroscience research and applications.

Incidental findings in brain scans

What to do when unexpected results appear in brain scans of normal research subjects.

Guide RNA (gRNA)

Clustered Regularly Interspaced Short Palindromic Repeats

DNA cutting system

Guide RNA (gRNA) recognizes a sequence of DNA and a protein (Cas9) breaks the DNA

Cell can repair the DNA (usually makes mistakes that mutate the gene) or donor DNA can be provided to fill in the broken spot

Cas9 protein

A protein that cuts DNA at a specific location as directed by gRNA.

Neuroethical Topics

Topics include cognitive enhancers, animal research, germline DNA editing, and fMRI imaging as a lie detector.

Fludoxyglucose (FDG)

PET measures glucose use

More glucose used = more brain activity

Mind controlled robotic limbs and exoskeletons

Motor cortex activity is recorded with implanted electrodes or EEG

Pattern of activity is used to train and instruct robotics

Jan Scheuermann feeds herself chocolate with a robotic arm

Amphetamine (Adderall), methylphenidate (Ritalin), Modafinil (Provigil)

Increase dopamine and/or epinephrine in basal ganglia and frontal cortex

May affect motivation, energy, confidence more than cognition

Applications of TMS

Research, treatment.