Dear Takahiko
I have found the vibrations to be caused by eddy currents in the aluminium grill on the IR lamp. Since the lamp is mechanically coupled to the camera this can be a problem with powerfull gradients. Our solution has been to mount camera and lamp with individual suction cup on a large plate located at the bottom of the scanner.
Best
Torben
> Den 30. maj 2021 kl. 04.12 skrev Takahiko Kawashima <[log in to unmask]>:
>
> Dear all,
>
> This is not an SPM thing, but please let me ask here since I couldn’t find better options.
>
> I am setting up a task fMRI experiment with eye tracking using Eyelink 1000 on Magnetom 7T (Siemens) scanner.
> I found that vibrations coming from the scanner were transmitted through the Eyelink apparatus, leading to vibrations of the gaze target in 2-3 degrees.
> The mount for our Eyelink is custom-made for 7T MRI by a vendor, and also we made a base to put the mount on using a 3D printer. These appear to fit the patient bed, but perhaps they amplify the vibration from MRI somehow.
>
> Does anyone has ever experienced a similar phenomenon?
> I’d appreciate it if you have any suggestion to solve this issue.
>
> Best regards,
>
> Takahiko
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