A Functional and Structural Investigation of the Human Fronto-Basal Volitional Saccade Network
Figure 4
Overview of group activation patterns (T-maps) for three tasks. The figure was split into panels A and B as combining activation overlays obscured too much detail due to overlap. Panel A at the left shows event related anti vs prosaccade activation in blue and saccades in darkness activation in red. Panel B at the right shows activation for visual stimulation vs rest in green and again for saccades in darkness vs rest in red. Overlap is rendered in yellow. In the upper row of panel A and B group activation is rendered in 3D on top of a high-quality individual (MNI normalized) skull stripped brain, only to indicate the location of activation with respect to the main sulci and gyri. In the right 3D rendering in panels A and B the anterior upper right part of the brain is cut out to show activation in deeper sulci and along the medial wall of the cortex. In the lower rows activation is overlaid on selected 2D slices through the T1 weighted normalized anatomical scan averaged over all participants, providing a more realistic impression of anatomical precision after normalization. Slice MNI coordinates are given for each slice at the upper right hand side (z-coordinate for axial slices, y for coronal and x for sagittal slices). Activation for all renderings is thresholded at T = 3.5, implying that also some stronger trends are displayed for the sake of completeness. See table 1 for an overview of statistics. Slices are displayed in neurological convention (left = left). Labels are indicating regions of interest or sulci. Lateral and medial FEF (frontal eye fields): two foci activated during saccades in darkness vs rest; antisaccade FEF: preferentially activated for antisaccades vs prosaccades (note that FEF label is only used for sake of simplicity; lateral activations are probably not part of the human FEF homologue). SEF: supplementary eye fields; PUT: Putamen; CS: central sulcus; SFS: superior frontal sulcus; CS: central sulcus.
