The Neural Basis of Mark Making: A Functional MRI Study of Drawing

<div><p>Compared to most other forms of visually-guided motor activity, drawing is unique in that it “leaves a trail behind” in the form of the emanating image. We took advantage of an MRI-compatible drawing tablet in order to examine both the motor production and perceptual emanation of images. Subjects participated in a series of mark making tasks in which they were cued to draw geometric patterns on the tablet's surface. The critical comparison was between when visual feedback was displayed (image generation) versus when it was not (no image generation). This contrast revealed an occipito-parietal stream involved in motion-based perception of the emerging image, including areas V5/MT+, LO, V3A, and the posterior part of the intraparietal sulcus. Interestingly, when subjects passively viewed animations of visual patterns emerging on the projected surface, all of the sensorimotor network involved in drawing was strongly activated, with the exception of the primary motor cortex. These results argue that the origin of the human capacity to draw and write involves not only motor skills for tool use but also motor-sensory links between drawing movements and the visual images that emanate from them in real time.</p></div

Brain activations for copying: Lateral view.

<p>a) Copying vs. fixation. b) Copying vs. mark marking. Data are corrected for multiple comparisons using FDR p<0.01. See legend to <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0108628#pone-0108628-g002" target="_blank">Figure 2</a> for abbreviations.</p

Talairach coordinates for copying and perception.

<p>Stereotaxic coordinates are in millimeters along the left-right (x), anterior-posterior (y), and superior-inferior (z) axes. In parentheses after each brain region is the Brodmann area, except for the cerebellum, in which case the anatomical labels of Schmahmann et al. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0108628#pone.0108628-Schmahmann1" target="_blank">[46]</a> are used. Due to the excessive number of activation foci for copying and perception, we decided to eliminate foci with a t value less than 8.0. The data in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0108628#pone-0108628-t001" target="_blank">Table 1</a>, by contrast, includes activation foci with a t value as low as 6.3. Abbreviations: IPS: intraparietal sulcus; LO: lateral occipital complex; MT: middle temporal; SMA: supplementary motor area.</p><p>Talairach coordinates for copying and perception.</p

Tasks and stimuli for the study.

<p>Representative stimuli and responses for two of the drawing conditions. In mark making, the name of a geometric figure and a direction for drawing it are presented. Blind drawing (not shown in the figure) has exactly the same stimuli, but no response is observable on the drawing tablet. In copying, an object and a starting point for drawing are indicated, and the subject creates a copy of the object in the space to the right, with the object continually in view.</p

Brain activations for mark making.

<p>a) Mark making vs. fixation. b) Mark making vs. blind drawing. Data are corrected for multiple comparisons using FDR p<0.01. Activations shown in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0108628#pone-0108628-g002" target="_blank">Figures 2</a>–<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0108628#pone-0108628-g005" target="_blank">5</a> are rendered onto an inflated brain of one of the subjects in the study (Subject 4) as normalized into Talairach space. The color bars in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0108628#pone-0108628-g002" target="_blank">Figures 2</a>–<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0108628#pone-0108628-g005" target="_blank">5</a> reflect the t score of the activated voxels for a given contrast. Abbreviations: FEF: frontal eye fields; IPS1/2: segments 1 and 2 of the intraparietal sulcus; IPS3/4: segments 3 and 4 of the intraparietal sulcus; MFG: middle frontal gyrus; MT: middle temporal; SMC: sensorimotor cortex; SPL: superior parietal lobule.</p

Brain activations for copying: Medial view.

<p>a) Copying vs. fixation. b) Copying vs. mark marking. Data are corrected for multiple comparisons using FDR p<0.01. The left side of the slices is the left side of the brain, as indicated by the L (left) and R (right) symbols. The Talairach z coordinate is shown below the slices. Abbreviations: IFG: inferior frontal gyrus; SMA: supplementary motor area.</p

Two channels of processes which should not run simultaneously.

<p>Two channels of processes which should not run simultaneously.</p

The algorithm of channel selection module.

<p>The algorithm of channel selection module.</p

The overall structure of logic channel controller.

<p>The overall structure of logic channel controller.</p

Engine model variables.

<p>Engine model variables.</p