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Technologies for Acquisition: How we obtain data

We use a range of neuroimaging instruments to measure signals that are known to reflect the underlying brain activity or structure.

Non-invasive neuroimaging techniques used include:

  • Magnetic Resonance Imaging (MRI)
  • Magnetoencephalography (MEG)
  • Optically Pumped Magnetometers (OPM)
  • Electroencephalography (EEG)

In addition, we have the possibility to stimulate the brain non-invasively using:

  • Transcranial direct current stimulation (tDCS)
  • Transcranial magnetic stimulation (TMS)

Or invasively via:

  • Deep Brain Stimulation (DBS)
  • Elastic Net Electrochemistry (ENE)

These technologies provide both direct and indirect measures of the brain’s function and structure. The ongoing activity of neurons causes changes in electrical and magnetic fields, which we detect from the surface of the head using MEG and EEG. This neuronal activity also causes changes in blood flow around the brain (hemodynamics), which we measure using functional MRI. We also use MRI to investigate the physical structure of the brain (structural MRI).


Core Technologies


Magnetic Resonance Imaging (MRI) is a non-invasive imaging technique that can be used to do things like map brain structure and detect brain activity. For example, functional MRI detects changes in blood flow and oxygenation associated with neural activity in the brain that occurs when the person being imaged carries out a specific task.

Our Centre was the first in the world to:

  • Generate Statistical Parametric Mapping and Voxel Based Morphometry analysis techniques for MRI
  • Produce a complete generative model of fMRI signals, which led to Dynamic Causal Modelling


Magnetoencephalography (MEG) is a non-invasive brain imaging method allowing neuroscientists and clinicians to view electromagnetic changes resulting from brain activity at the millisecond timescale.

Our Centre was the first in the world to:

  • Combine invasive recordings from wires implanted in the brain with non-invasive recordings using MEG.
  • Develop novel approaches for high-precision, high signal-to-noise MEG. This has established the possibility to reliably and non-invasively record, electrophysiological signals from deeper brain structures, and from cortical structures with laminar specificity


Electroencephalography (EEG) is a non-invasive method used to measure electrical activity from neurons in the brain.

Like MEG and OPMs, it provides high temporal resolution, with the added advantage over conventional MEG of being portable, enabling it to be used in the laboratory or at the patient’s bedside.  However, it has limited ability to localize where in the brain the signals are coming from.

Our Centre was the first in the world to:

  • Implement dynamic causal modelling
  • Apply these different biophysical models to study both healthy and pathological brain states (like coma).


Optically pumped magnetometers (OPMs) constitute our ground-breaking wearable MEG system, developed in collaboration with the University of Nottingham.

OPMs operate without cooling and can be placed directly on the scalp surface, making this a wearable device.  The sensors are small (~1cm3) which increases the spatial resolution at which we can measure brain activity. Our simulations show that the decrease in brain-to-sensor distance offered by the new OPM sensors will facilitate a 5-fold increase in sensitivity and spatial resolution for the typical adult cortex. This will increase the signal to noise ratio, allowing us to look at MEG signals from much deeper brain structures.

Our exciting new device brings novel technical challenges. The increase in signal to noise requires our MEG models to be more precise. We are therefore optimising our MEG analysis models to increase the signal to noise to provide a new generation MEG system, with unparalleled performance.


Other Technologies


Transcranial Direct Current Stimulation (tDCS) is a non-invasive method that passes small electrical currents directly on the scalp, to stimulate the nerve cells in the brain.

The potential clinical application of tDCS is an active area of research.


Transcranial Magnetic Stimulation (TMS) is a non-invasive procedure that uses magnetic fields to stimulate nerve cells in the brain.

It is commonly used to temporarily change the activity or connectivity of a region of the brain, to better understand that region’s normal function.


Deep Brain Stimulation (DBS) is an invasive surgical procedure involving the implantation of a medical device called a neuro-stimulator (sometimes referenced as a ‘brain pacemaker’). The neuro-stimulator sends electrical impulses, through implanted electrodes, to specific brain regions. It is only conducted in patients who do not respond to other treatments. For example, when a person has severe tremor caused by a neurological condition such as Parkinson’s disease, DBS may be used after other treatments have been explored.


Elastic Net Electrochemistry (ENE) can be used to detect rapidly changing electrochemical signals from human brains.

The machine learning technique, pioneered by Read Montague, can measure rapidly changing local concentrations in neuromodulators such as dopamine and serotonin. (Kashida 2016, Moran 2018) This technology can be used with electrodes that are routinely used in patients with epilepsy.

Understanding the factors that regulate neurotransmitter function will, in the future, provide a better understanding of conditions such as schizophrenia, addiction and depression which are already known to be connected to dysregulation of neurotransmitter signalling.

Statistical Parametric Mapping

Our leading software for analysing neuroimaging data was developed at FIL.

Find out more about SPM