fMRI on the Nottingham 7T scanner
Imaging techniques:
We routinely acquire whole head, single shot gradient echo EPI for fMRI. Typical acquisition parameters include:
- 1x1x1 mm, TR= 2.2s, number of slices = 22
- 2x2x2 mm, TR= 2.4s, number of slices = 30
We also have multiecho versions of this sequence used to monitor changes in R2* dynamically.
We have also developed whole head, single shot spin echo EPI for fMRI with similar acquisition parameters
Single trial fMRI
Primary sensory areas can produce BOLD signal changes of 20%, opening up the possiblity of studying single trial fMRI. We designed Paradigm Free Mapping software which allows single trial response to be detected from the signal time course with no prior knowledge of the stimulus paradigm.
Stimulus presentation and monitoring
We have a range of presentation systems available:
- Visual: prism spectacles, mirrors and data projector
- Auditory: in ear speakers
- Somatosensory: piezoelectric vibrator, air puffs
- EMG for monitoring movement (and also swallowing and eye blinks)
- Video camera for monitoring gross motion
Combined electrical and haemodynamic measures
We have demonstrated that our Brain Products EEG system can be used for simultaneous EEG/fMRI studies at 7T. This system is also used to measure Galvanic Skin Resistance and various EMG signals. We also have an MEG scanner next to the 7T scanner allowing correlation of the MEG and MRI data.
Quantitative measures of brain activity
We have developed and validated at 7T a number of methods for measuring parameters related to the haemodynamic response:
- Cerebral Blood Flow using Arterial Spin Labelling both at high temporal resolution or for large volume coverage applications
- Arterial blood volume (aCBV) using Arterial Spin Labelling
- Total blood volume (CBVt) using contrast agents to modulate intravascular susceptibility.
We also have a RespirAct system to allow independent control of end tidal CO2 and oxygen, for hypercapnia and hyperoxia experiments.
Below are some images related to our fMRI at 7T. Please click the images to enlarge them.
 EMG system |
 Somatosensory stimulator |
 Recording motor response |
 Visual presentation system |
 Whole head EPI |
 1mm isotropic GE EPI |
 1mm isotropic GE and SE response to visual stimulation |
 1mm isotropic SE and GE with somatosensory stimulus |
 1.5 mm isotropic ASL acquired with FAIR |
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