Dear SPMers
We would like to minimise the signal loss due to field inhomogeneities in
the inferior temporal region but do not want to compromise signal in the
rest of the brain. Pilot testing of our visual working memory task has
produced activation in frontal, parietal and occipital regions, but not in
the hippocampal regions, as expected.
We are using a Phillips 3T system; the slice tilt is aligned to the AC-PC,
FOV: 240mm,Matrix: 112x128x80,Flip angle: 90. TE 30ms, TR 2020ms.Phase
encode gradient is posterior.
Are there any ideas on how to improve signal in the inferior temporal
lobes? I have read Weiskop et al NeuroImage 33 which suggests EPI
parameters to maximise signal in specific regions eg hippocampus, but this
seems to be at the expense of reduced/distorted signal in other brain
areas. Also control of z shimming gradient is not possible on our system.
Nicky Kochan
Neuropsychiatric Institute, University of NSW, Australia
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