CORTICAL LOCALIZATION OF HUMAN SUSTAINED ATTENTION - DETECTION WITH FUNCTIONAL MR USING A VISUAL VIGILANCE PARADIGM

Purpose: Our goal was to determine whether functional MRI on a standar d 1.5 T system can localize activation during a visual vigilance susta ined attention task and whether this corresponds to results described in a PET investigation of a similar task. Method: Sixteen volunteers w ere studied on a 1.5 T system using a gradient echo technique. A singl e axial section was oriented within a stereotaxic coordinate space, 40 mm superior to the anterior-posterior commissure line. Images with ey es closed were followed by images during subject concentration on a sm all dim spot. Motion correction and pixel-by-pixel statistical analysi s were performed. Talairach grids were applied for summary statistical analysis and comparison to PET data, with analysis using a series of planned contrasts within a repeated measures analysis of variance. Res ults: Predominantly right-sided frontal and parietal activation was ob served, with statistical significance across subjects in the right fro ntal lobe (F greater than or equal to 5.9, p less than or equal to 0.0 41). Comparison with previously reported PET data yielded a very simil ar pattern of activation (F = 13.2; df = 1.8; p = 0.007). Conclusion: Activation of the right middle frontal gyrus and right parietal lobe d uring visual vigilance is detectable across functional imaging modalit ies.