5. Pre-Scan: Stimulus Delivery and Response Equipment

The stimulus equipment should be set up prior to the arrival of the participant.

[Note]Before You Start

Check the Experiemtal Setup Sheet for the study you are scanning. It may be found in the MEG study setup folder, near megmap. You are advised to do the following checks based on the information in the Experimental Setup sheet, to verify that the stimulus and response setup is correct. You may need to do this with the experimenter (but not the participant) present; in which case, you will need to liaise with the experimenter to organise this. These are things that need to be checked:

  • Be aware of what visual and/or auditory stimuli will be used in the study.
  • If it is a visual study, is the experimenter using E-Prime / Presentation / Python software? Or another package bespoke to their study? If the stimulus presentation is atypical, familiarize yourself with the required stimulus setup, and consult Appendix E (MEG Wiring Diagram) to set the stimuli up.
  • Are responses being collected? If so, what is the response device; Peanut or Lumitouch? And which buttons are to be used?
  • If the study uses auditory stimuli, or a default E-Prime / Presentation / Python visual stimulus setup, is the auditory trigger BNC in Channel 1 of the Trigger Inputs section of the DAS? Alternatively, if the study uses a bespoke trigger setup, consult the Experimental Setup sheet, and set up the appropriate triggers.

5.1. Visual Stimulus

5.1.1. Projector

Turn on the power to the projector by pressing the “Power On” touchpad which is located on the upper side of the projector. The power indicator will turn green. When turning on the projector, you also need to turn on the white fan next to the projector; if the fan isn't turned on, the projector is liable to overheat.

N.B. If the power is turned off and then immediately turned on again, it may take a short while before the lamp turns on.

If ON is pressed twice, the POWER indicator will light up orange and the cooling fan will run for about 90 seconds. The projector will then enter “Standby Mode”.

N.B. The power can be turned on again by pressing the ON button.

5.1.2. Screen

Once the projector is on, you need to check that the image is being projected appropriately onto the screen. Check the three following things:

  1. Is the image being projected on the screen?

    If the image is not being projected, refer to the troubleshooting guide.

  2. Is the position of the image correct?

    If the image is not being projected, refer to the troubleshooting guide.

  3. Does it need to be mirrored / inverted? To mirror or invert, use the remote control change the image. These functions may be found by pressing Menu and then:

    1. Scroll up / down to “Main”.
    2. Scroll right to “Mirror”.
    3. Scroll right to the Mirror Menu.
    4. Scroll up / down as appropriate and select “Normal”.