Microteaching

Introduction to Neuroimaging

Alison Cooper

Introduction

As an introduction to your 1st year methods course in Brain and Behaviour will look at the following questions:

1. What Neuroimaging and modulating techniques are currently available in Psychology?

2. How do they work?

3. What do they measure?

4. How can they be used in Psychology?

5. What are the challenges and future possibilities?

About Me

Education• PhD Neural Basis of Sleep and Learning Using a Novel Artificial Language,

Surrey 2014 to date • MSc Cognitive Neuroscience, York 2013 • Postgraduate Diploma in Science Communication, Birkbeck 2005• MPhil Neuroscience, Birmingham, 2002• BSc Hons Psychology, Sheffield 1996

Engagement activities: Museums and Education, Science Writing, Journalism and Podcasts, Science Festivals and School Outreach e.g ‘Mind the Gap’ and ‘Smarter UK’, initiatives on Neuroenhancement, Photography

Teaching assistant at 4 Universities and management roles in Research Project Management, Researcher Development and Policy (e.g ethics), at 4 Universities and a Research Charity

About You?

• Do we have any Psychologists, Neuroscientist, Physicists, Biologists or Medics here?

• Has anyone ever had an MRI scan?

• Are you are aware of any other techniques ?

• Complete beginners?

Fine, this is an introduction for everyone.

Beauty and the Brain

Some of the following images are neuroimaging/stimulation techniques, others are beauty treatments.

Which are which?

Beauty or Brain?

Brain• This is tCDS

• Transcranial Direct Current Stimulation

Beauty• This is CACI

• Facial using low current stimulation

Beauty or Brain?

Beauty• This is an African Mask• Mask of vegetable fibre, hair

and red abrus seeds, British Museum

Brain• This EEG

• Electroencephalography

Beauty or Brain?

Beauty• This is hairdryer

• A 1960s hood hairdryer and a shower cap

Brain• This fMRI

• Functional Magnetic Resonance Imaging

Beauty or Brain?

Beauty• Wireless Permanent-Waving

Machine, 1934• Designed by Icall, the heaters were

disconnected before applying to the head

Brain• This MEG

• Magnetoencephalography

Beauty or Brain?

Brain• This is TMS

• Transcranial Magnetic Stimulation

Beauty• This is hair foils

• Applied to hair to give highlights using bleach

How do they work?• fMRI scanners have magnetic fields inside which align the nuclei of

hydrogen atoms in water of the blood. This produces activation maps showing parts of the brain, requiring more oxygen for energy, which is transported by the blood during a mental process. Magnet

• MEG records magnetic field produced by electrical currents occurring when neurons communicate, using sensitive magnometers. Magnet

• TMS, a magnetic field generator, or "coil” placed near the head produces small electrical currents in the region of brain just underneath via electromagnetic induction. The stimulation can be used to test the function of the region. Magnet

• tDCs, low direct current is sent through electrodes placed in the region of interest, the induced current flow increases or decreases the neuronal excitability in the area, altering brain function. Electric

• EEG does NOT use magnets and measures electrical voltage fluctuations resulting from ionic current flows within neurons of the brain. Electric

MeasurementsAbout the Brain

• A 3D structure, rounded, folded

• Can be cut in 3 ‘planes’, coronal, frontal, sagittal

• Coordinates calibrated from central point – anterior commissure

• Electrical signaling, within neurons

• Chemical signaling between neurons

• Signals measured in space & time

• Signal levels can be linked to events such as task or stimuli

• Computer models reconstruct the signals to locate and visualise

About the signals

• fMRI – BOLD signal, metabolic energy use in the brain, spatial, maxima and minima, structure, grey matter, white matter, fluid

• MEG – neural signaling from dendrites, close to surface, in sulci (folds), high time accuracy, computer model to visualise spatially on fMRI structural scans, frequency bands, maxima and minima

• EEG – electrical signals, trace back to sensors, frequency bands

• TMS/tDCS – the measurements are from the task performed, currents are applied to selected regions

EEG DataIndependent component analysis of Cortical Dynamics using EEG

Audio and neural data during auditor saliency task

fMRI Data

MEG DataReading Task

Sensor data – all frequencies over time Distribution of stability

beamformed (modelled) onto fMRI structural scan

Stockwell time frequency plots at virtual

Electrode coordinates Inferior Frontal Gyrus

Left

Right

What Can Neuroimaging Tell Us?It can ‘read my mind’

It can diagnose disease?

It can tell if I am awake

It can erase my thoughts

It can give me superpowers

• No, but neuroimaging research aims to discover what happens in the brain viewing stimuli and performing tasks

• Yes, both structural and functional imaging can indicate abnormality, confirming a problem requires scanning by clinicians

• Sometimes, the bran has different ‘resting states’, MEG and EEG can show frequencies linked to sleep, anxiety and alertness

• No, TMS can disrupt brain regions to demonstrate their role e.g in speech, but this effect is brief and temporary

• Not yet, tCDs can improve performance on some mental tasks for a short time

Examples in Psychology

Task: Imaging and Stimulation can be used in nearly every area of Psychology. Choose a card with one of the techniques, write an area you would use it to study on the back and pin it on a clip.

Examples

• Reading• Face recognition• Mirror drawing (motor)• Emotion processing• Perceiving motion• Problem solving• Speech production

Recap• The Good – studying cognition in awake and performing humans, fMRI

and MEG reasonably safe and non invasive

• The Bad - fMRI delayed response not accurate for timecourse, MEG poor spatial especially for deep structures. Scans are time limited, snapshot, repeat scanning but not good for longitudinal studies. Tasks are restricted by scanner, have to be in a lab, little movement from participants, risk from magnets if metal in the body, expensive.

• The Ugly – dependent on computer modeling assumptions and skills of interpreter, confounds of task design, small samples and individual variation

• The Future? Smaller portable devices, test in real life situations, less controlled conditions, privacy, unintended use, possible damage to equipment.

Further Action• ‘What can Psychologists see using brain imaging?’

• Assignment – choose one of the techniques from today and write a 500 word rationale for a Psychology experiment you would use it for, use the supporting paper for your chosen method to help you

• Further help – there will be in depth lectures on each technique and their use in Psychology during the remainder of the course and tutorial sessions on experiment design –see Surrey learn for schedule

• See handout for reading list – Thank You!