The Forp (Fiber Optic Response Pad) is a
fiber optic based device which serves as a response pad for
fMRI studies. The pad is designed to fit in the hands and consists of anywhere from two to four brightly colored
gameboy buttons which the subject uses to respond with during a given
study. The response pad is completely
non-metallic and non-electronic and intended for use in
MRI,
MEG or other environments where
metal or
electronics could hinder data acquisition or degrade image quality. Complete electrical isolation of the response pad and fiber bundle eliminates any potential danger of
electrical shock. In fact, the pad is constructed using no metal parts and instead of being electrical, the plastic switches are light-based.
The Forp also consists of a shiny metal box which serves as the interface unit between the button pad and the recording computer. The aluminum box translates the button presses into key presses for both the Mac and PC so that they can be recorded using testing programs such as Psyscope. In addition to the handheld device, it is possible to hook the MRI machine itself into the interface unit, utilizing a triggering capability which can help synchronize the MRI scanner function to the psychometric data acquisition system.
The response pads come in 4 different styles as well as custom built designs:
- Diamond Pattern (4 Buttons)
- Bimanual (2 pads, 1 button each)
- Bimanual (2 pads, 2 buttons each)
- In-line (4 buttons)
To put it simply, the Forp is a godsend to anyone doing an fMRI study because it gives the researcher accurate response times reported directly to a computer and the manner of response is so simple that it does not interfere with the study in any way. Only problem is that Current Designs, Inc, the manufacturer, knows its worth and charges an arm and a leg for it. Oh well.
Completely unrelated, Forp is also the
acronym standing for the
Fiber Optic Respiratory Plethysmograph, a technique used with MRIs to distinguish and measure movements in the chest caused by the heart rather than movement caused by the patient's breathing.