The neuroscientific exploitation of high-resolution functional magnetic resonance imaging

Abstract

High-resolution functional magnetic resonance imaging (hi-res fMRI) promises to bridge the gap between the macro- and the microview of brain function afforded by conventional neuroimaging and invasive cell recording, respectively. Hi-res fMRI (nominal voxel sizes < or = (2 mm)3) is robustly achievable in human studies today using widely available clinical 3-Tesla scanners. However, the neuroscientific exploitation of the greater spatial detail poses three challenges: (1) Fine-scale neuronal activity patterns are inaccurately depicted in the hemodynamic images obtained. (2) Single small voxels yield very noisy measurements. (3) For groups of subjects, the interindividual correspondency mapping is unknown at the fine scale of millimeters. Here we argue that these challenges can be met by abstracting from the regional fine-scale activity patterns themselves and instead asking how well they distinguish the experimental conditions.