The scanner as a psychophysical laboratory

Abstract

There has been steady progress, both in individual laboratories and in the development of integrated commercial systems, for the sophisticated control of stimulus presentation and response recording during magnetic resonance imaging (MRI). This chapter articulates some of this progress and the general considerations for anyone establishing a functional MRI research environment, focusing on the latest developments relevant to an investigator establishing their own psychophysical laboratory in the magnet. The technical problem of stimulus presentation and response recording provides a brief discussion of the general need to adapt the psychophysical tasks themselves to be more compatible with the MRI environment. The chapter also discusses stimulus presentation, subdivided by modality (visual, auditory, tactile, etc.) and voluntary response recording, and furthermore deals with physiological response recording, head movement and related safety issues. Finally, it discusses the tradeoffs between commercial systems, custom designed systems and the goal of a completely integrated psychophysiological laboratory in the MRI environment.

The Statistical Analysis of Functional MRI Data

“…Subjects can go through training prior to the experiment, in either a simulated or real scanner, to become adjusted to the environment and learn how to minimize head motion. Masks and plaster head casts which are molded to the subject's head and face, and then bolted into position, are an effective means of reducing motion, but some subjects find them uncomfortable and anxiety-inducing (Savoy, 2001). Also in wide use are bite bars, in which the subject bites down on a dental mold throughout the course of the scanning session.…”

Functionele MRI (fMRI) ’ Inleiding en technische achtergrond

“…verschillende niveaus van een taak) en factorie¨le designs toegepast. Voor een uitgebreidere beschrijving van de experimentele opzet verwijzen wij naar de literatuur (zie bijvoorbeeld Donaldson & Buckner, 2001;Savoy, 2001).…”