A NONFERROUS INSTRUMENTAL JOYSTICK DEVICE FOR RECORDING BEHAVIORAL-RESPONSES DURING MAGNETIC-RESONANCE-IMAGING AND SPECTROSCOPY

A nonferrous joystick device was developed to permit subjects to conti nuously report ethanol-induced alterations in subjective mood states w hile undergoing a magnetic resonance imaging (MRI) and magnetic resona nce spectroscopy (MRS) procedure. The device utilizes air pressure (su pplied by a small compressor) that is directed to a series of tubes th at terminate in a hand-held unit. The hand-held unit easily fits insid e the magnet and resembles a standard computer game joystick except th at the ends of the air hoses replace the buttons. The control unit con tains three pressure transducers, which are triggered when the tubes a re occluded by the subject, activating different pens on an event mark er located 6 m from the whole body imager. The unit is safe to use ins ide a 1.5-Tesla magnetic field and does not disrupt the MRI and MRS re cording procedures. Subjective reports of ethanol-induced euphoria and intoxication paralleled the MRS detection of ethanol in the brain. Th is device could prove to be useful in numerous behavioral studies invo lving whole-body MRI and MRS.