Stimulus Presentation and Peripheral Equipment

Stimulus Presentation
While not used in every fMRI study, a majority of the research currently being done involves some form of auditory or visual stimuli being presented to the subject while inside the MRI machine. Here we'll present just a few of the equipment solutions available at the BIC. At the bottom of the page you can find equipment documentation, including an updated 3 T Peripherals Equipment Guide, which gives a broad overview of what we have available for use.

The visual stimuli are presented to subjects using a modified MRI-compatible projector from Avotec that is placed at the rear of the magnet. The images are projected onto a specialized plexiglass screen with a non-dispersing optical coating, and the subject views the projected images using one of our custom-built mirror systems.

Researchers are able to provide stimuli using a PC (loaded with E-Prime 2.0), a Mac (loaded with Matlab 2016a and the Psychtoolbox add-on), or they can bring in their own computer and easily connect up to our system. Our goal is to offer multiple solutions to fit the needs of all our users.

The BIC has two auditory stimulus delivery systems available for use; the standard Siemens pneumatic audio system and an earbud system by Sensimetrics designed to fit comfortable inside the 32 Ch. head coil. BIC staff have also designed custom pneumatic headphones that fit inside the 32 Ch head coil that can be swapped with the standard Siemens headphones for use with their system. We also have an MRI-compatible optical microphone for recording subject voice responses.

MRI-Compatible Response Devices
Subject responses to visual and/or audio stimuli can be collected using our MRI-compatible response devices. The BIC has several different response devices, including 4-button pads, 5-button pads, and force grip sensors. All our devices are supplied by Current Designs.

Laptop Recommendations
If you plan on using your own laptop to provide stimuli there are several considerations that must be made to make sure it is compatible with the BIC's projector and audio systems. So far most labs have only been concerned with making sure they can get video + audio out and a USB port for the MRI-compatible response devices button (which also deliver the TTL pulse from the magnet). However modern laptops have a habit of removing/changing ports every few years. So depending on whatever the video OUT for your potential laptop is (USB-C or HDMI are currently the most popular) and whatever the audio OUT is (if you are lucky a standard audio jack but it might be via USB-C or something new!) you may need to buy some additional adapters to allow it to hook up to our setup. So long as you can convert the video to VGA and the audio to a standard 3.5 mm jack then everything should play nice. But please be aware that not all adapters are created equally so it may take a while to find one that works. You may find that one we have here at the BIC works just fine for you as we since we have several available on hand. Once you begin outputting VGA just make sure it's set to 1024x768 resolution with a refresh rate of 60 Hz and that should do it for the video signal

If you plan to use the EyeLink eye tracker just know that it hooks up to stimuli computers via a crossover ethernet cable, so that would require an ethernet port on the laptop or a USB-to-ethernet adapter. If you don't have any other specific piece of equipment you need to plug in that requires something other than USB then nothing else is required.

MRI Compatible Prescription Goggles
In case some subjects require prescription lenses to see clearly, our MRI compatible goggles are available for use.

The standard goggles can be worn comfortably inside the 12 channel head coil. Using the prescription lenses with the 32 channel head coil requires the use of a custom built adapter that secures the lenses in place on the coil itself.

Eye Tracking
Our older eye tracking setup consists of a camera system from Avotec and software from Arrington Research. We bought an Eyelink system from SR Research a few years ago, but continue to maintain both systems to allow more flexibility for our users.

Physiological Monitoring
The BIC is equipped with the Biopac physiological monitoring system. With this system our researches are able to monitor and record a variety of physiological information, including pulse oximetry, respiration movement data and end-tidal %CO2 and %O2.

Equipment Training Documents

Peripherals Checklist
Biopac and Acqknowledge Guide
Mirror Setup Guide
3 T Peripheral Equipment Guide
BIC Avotec Eyetracking Guide
Viewpoint User Guide
Calibrating GSR in Biopac