A patient named Mrs. S. suffered a stroke. After the stroke, Mrs. S. remained an intelligent, funny woman. However, she no longer had any understanding of the concept of “left.” When she ate her meals, she would only eat from the right half of the plate, and when looking for lost objects she’d only seem to search the right half of her visual field. Mrs. S. learned to compensate for her restricted vision, however. Because she could no longer turn left, she learned to turn right through a circle, until previously unseen objects came into view. When applying her makeup, Mrs. S. couldn’t see the left side of her face, but by staring at a video feed of her face—in which the left and right sides are reversed—she could apply the makeup to the other side. In the Postscript, Sacks notes that videos and computer simulations may become important for helping people like Mrs. S.
In this intriguing case, Mrs. S.’s stroke leaves her incapable of conceiving of “left” in the ordinary way. Therefore, she has to adjust her behaviors and movements to her new neurological impairment. She finds various ingenious work-arounds, showing how even (and perhaps especially) people with series neurological problems can adapt to their changing circumstances. Furthermore, the rise of personal computers (which, at the time when Sacks composed this chapter, was an ongoing process) might help people like Mrs. S., perhaps by training them to recover their spatial awareness.