“Mirror-writing” is the simultaneous process of reversing individual letters and composing word strings in reverse direction. It is reported that the lesions which cause “mirror-writing” are left parietal lobe, left basal ganglia, right supplementary motor area, left supplementary motor area, left cingulate gyrus, and left angular gyrus. To explain this phenomenon, several theories have been proposed such as the motor, the visual dominance, the supplementary motor area, the visio-spatial, the visual word- form, the hemisaptial factor or directional and the reflected graphemic representation hypotheses. With reviewing some of literatures, we present a case of “mirror- writing” of posterior corpus callosum lesion which is not included in the aforementioned those. (J Korean Acad Rehab Med 2007; 31: 351-355)
Mirror writing is script that runs in the direction opposite to normal, with individual letters also reversed. A Right handed woman suddenly developed mirror-writing. After traumatic brain injury without definitive lesions on MRI, she could not discriminate between right and left by herself. Several theories, including motor, visual dominance, spatial disorientation and supplementary motor hypotheses, have been proposed to explain such. We believe that availability of mirror engrams induce reversal of normal left-to-right writing pattern including mirror-writings.