Figure 1. Summary of all effective vs null results.

Summary of effective (red) and null (black) results. The overall elicitation rate was 17.4%: stimulation at n = 30 electrodes yielded some reliable subjective effect, whereas stimulation at 142 electrodes elicited no effects (right panel). The elicitation rate differed significantly along an anterior-posterior axis (results displayed for 143 electrodes, where Montreal Neurological Institute coordinates were available; see Methods): between y-coordinates 20 and 40, the rate was approximately 20% effective, whereas anterior to y = 40, the elicitation rate dropped nearly to zero. Electrodes from both sides of the brain have been projected onto a single hemisphere for clarity in demonstrating the gradient of the elicitation rate; for effects displayed bilaterally, see figures 2 and 3. Approximate Brodmann areas are indicated in gray numerals. Brain with Brodmann areas adapted from figure 2 in reference 5, modified and extended from the work of Öngür and Price.⁴²