Magnetic resonance imaging
The CHBH magnetic resonance imaging (MRI) laboratory houses a 3 Tesla scanner and an MRI simulator (mock scanner), with both systems providing a range of options for stimulus delivery and physiological and behavioural recordings.
The available equipment includes:
- Barco Projector (potentially up to 120Hz refresh rate),
- MR-compatible button boxes (NATA Response Boxes; 2x5 and 2x2),
- audio capture and transmission system,
- eye tracking (SR Research Eyelink Eye tracker),
- and limb movement tracking (3 Camera Qualisys Motion Tracker System).
In addition, facilities are available to support multimodal data acquisition, including MR-compatible 64 channel EEG and transcranial direct current stimulation (tDCS) systems. This equipment enables complex behavioural experiments with healthy participants and clinical populations. The mock scanner allows participants to be trained and/or acclimatised, which can be particularly useful for children and adult participants who are new to the MRI environment and advanced experimental setups.
The CHBH houses several MRI research groups with particular expertise in functional MRI, diffusion MRI, arterial spin labelling and MR spectroscopy, as well as concurrent EEG-fMRI.
The magnetoencephalography (MEG) laboratory houses a Neuromag TRUIX system. MEG allows for continuous recordings of ongoing brain activity with a millisecond time resolution. By using advanced analysis tools it is furthermore possible to identify where in the brain the measured electrophysiology activity is generated.
The TRIX system has 306 sensors distributed over the head: 204 planar gradiometers and 102 magnetometers. The MEG system is place in a two-layer shielded room. The system allows for conceurrent EEG recordings from 64 electrodes and continuous monitoring of the head position. A closed-loop He recycler elimintes refills.
The peripherals of the MEG system includes a:
- ProPixx projector (1440 refresh rate)
- a fast eye-tracker from EyeLink/SR Research
- auditory stimulation
- somatosensory stimulation
- button boxes
A dedicated MEG analysis pipeline, FLUX, is under development to facilitate research.
The functional near infrared (fNIRS) laboratory
The functional near infrared (fNIRS) laboratory houses the Imagent (v2) system. The Imagent system is based on the measurement of the propagation of near infrared light through tissue, allowing for non-invasive functional imaging of the brain. The Imagent system is a time resolved fNIRS system that measures the light intensity, the modulation of the light and the time taken by the light signal to traverse the illuminated area of the brain (or other targeted tissue).
This imaging technology together with model-based image reconstruction techniques (e.g. NIRFAST) provide a balance between temporal and spatial resolution for the study of superficially located areas of the human brain (typically up to 30 mm deep from the scalp). This imaging approach is able to detect variations in the blood oxygenation levels of activated brain areas and provide spatial maps of where these haemodynamic changes occur, thus combining the fast neurological signals (the event related optical signal) and the slow signals (haemodynamic changes) of the brain. The Imagent system features 64 emitters and 30 detectors, which provides 960 optical channels and has the capability of simultaneous whole-head imaging.
The system can be combined with EEG, TMS and MRI operations, as well as used in conjunction with typical stimulus-response tools to assess brain health (e.g. button boxes, cerebrovascular reactivity protocols).
The Sleep laboratories
The CHBH sleep laboratory houses two separate sleep rooms and a central control unit. Both rooms are equipped with BrainAmp© DC 64-channel EEG amplifiers. Customised sleep EEG caps ensure participant comfort and ease in experimental setup.
Peripheral equipment for experimental testing and stimulus delivery (eg. auditory cues) is provided. In addition, the suite offers dedicated transcranial electrical stimulation (tES) devices (neuroConn© DC-Stimulator Plus, CED Micro1401-3 data acquisition unit).
The CHBH houses a state-of-the-art Biosemi 128 channel EEG system with active electrodes. A high performance computer allows for accurate timing and application of auditory and visual stimulation (concurrently or separately). Electrode locations can be tracked with a Polhemus Fastrack and co-registered with individual MRIs for accurate source models. Eye-movements can be recorded and synchronized with the EEG system with a fast Eye-tracker from EyeLink/SR research. Analysis pipelines for analyzing time-frequency and time-locked data in the sensor space and source space have been developed and are available from leading researchers in the CHBH.