Two Cortical Systems for Reaching in Central and Peripheral Vision Jérôme Prado, Simon Clavagnier, Hélène Otzenberger, Christian Scheiber, Henry Kennedy, Marie-Thérèse Perenin  Neuron  Volume 48, Issue 5, Pages 849-858 (December 2005) DOI: 10.1016/j.neuron.2005.10.010 Copyright © 2005 Elsevier Inc. Terms and Conditions

Figure 1 Overview of Each Reaching Condition For the whole experiment, the screen in front of the subjects was a black semicircle on which red and white targets were projected at 5° or 10° on either sides of a green fixation cross. Gray and blue arrows represent, respectively, hand and eye movements. When the visual target was white, subjects had to reach at it under three different conditions, reaching to Visible Target after Saccade (VT/Se), reaching to Invisible Target after Saccade (IT/Se), and reaching to Visible Target with No Saccade (VT/NSe). When the visual target was red (not shown), subjects did not reach at target but only moved their eyes (VT/Sc and IT/Sc) or displaced covert attention (VT/NSc). FMRI events were time locked to the appearance of the visual target. Neuron 2005 48, 849-858DOI: (10.1016/j.neuron.2005.10.010) Copyright © 2005 Elsevier Inc. Terms and Conditions

Figure 2 Reaching-Related Activations for the Three Tasks (A) Simple main effect of reaching in the reach to Visible Target after Saccade task (VT/Se − VT/Sc). (B) Simple main effect of reaching in the reach to Invisible Target after Saccade task (IT/Se − IT/Sc). (C) Simple main effect of reaching in the reach to Visible Target with No Saccade task (VT/NSe − VT/NSc). The three contrasts are shown on superior and posterior views of a rendered three-dimensional brain of one of the participants (random effect analysis, voxel level p < 0.001, cluster level p < 0.05 corrected for multiple comparisons). PMd, dorsal premotor area; mIPS, medial intraparietal sulcus; POJ, parieto-occipital junction. Neuron 2005 48, 849-858DOI: (10.1016/j.neuron.2005.10.010) Copyright © 2005 Elsevier Inc. Terms and Conditions

Figure 3 Direct Comparisons between Tasks (A) Effect of the peripheral position of the target during reaching (interaction [IT/Se − IT/Sc] − [VT/Se − VT/Sc]) showing bilateral activation of the parieto-occipital junction (POJ). SPMs rendered into standard stereotaxic space and superimposed on to a sagittal and coronal MRI in standard space. For display purpose, the threshold for the whole brain was set to p < 0.005 (uncorrected). POS, parieto-occipital sulcus. (B) Boolean intersection of the two simple main effects of reaching in peripheral vision ([IT/Se − IT/Sc] AND [VT/NSe − VT/NSc]). Each simple main effect was thresholded at p < 0.001 (voxel level) and p < 0.05 corrected (cluster level) and superimposed on superior and posterior views of a rendered three-dimensional brain of one of the participants. Neuron 2005 48, 849-858DOI: (10.1016/j.neuron.2005.10.010) Copyright © 2005 Elsevier Inc. Terms and Conditions

Figure 4 Region of Interest Analyses Activity related to control (saccade) and experimental (saccade and reaching) conditions when the visual target was located in the central (VT/S task) or peripheral (IT/S task) visual field in the three bilateral regions of interest: dorsal premotor cortex (PMd), medial intraparietal sulcus (mIPS), and parieto-occipital junction (POJ). For each area, the graphs show the regionally averaged β weights averaged across participants. Error bars indicate intersubject standard error of the mean (SEM). Significant differences (p < 0.05) between reaching in central and peripheral vision relative to their respective control were observed in bilateral PMd (left, p = 0.019; right, p = 0.004) and POJ (left, p = 0.015; right, p = 0.024) but not in mIPS. Neuron 2005 48, 849-858DOI: (10.1016/j.neuron.2005.10.010) Copyright © 2005 Elsevier Inc. Terms and Conditions

Figure 5 Extent of PMd Activity in the Precentral Region (PrC) Left, voxels activated (p < 0.001 uncorrected; random-effect analysis) in the left and right PrC in the three tasks superimposed on the anatomical image of one participant. There were more voxels when pointing was performed in peripheral (VT/NS and IT/S tasks) than in central vision (VT/S). Right, change in volume of PMd activated in the left and right PrC averaged across participants. Bars show the volume variation because of the “peripheral-vision effect” (Vol[IT/Se − IT/Sc] − Vol[VT/Se − VT/Sc]) and to the “saccade effect” (Vol[IT/Se − IT/Sc] − Vol[VT/NSe − VT/NSc]). There was more volume variation (asterisk, p < 0.05) because of peripheral vision of the target than saccade in left PrC (p = 0.016). Error bars indicate SEM across participants. Neuron 2005 48, 849-858DOI: (10.1016/j.neuron.2005.10.010) Copyright © 2005 Elsevier Inc. Terms and Conditions