Selective directed forgetting is mediated by the lateral prefrontal cortex: Preliminary evidence with transcranial direct current stimulation.

Recent research has shown that providing a cue to selectively forget one subset of previously learned facts may result in specific forgetting of this information. Behavioral evidence suggests that this selective directed forgetting effect relies on executive control and is a direct consequence of active, rather than passive, mechanisms. To date, however, no previous research has addressed the neural underpinnings of selective directed forgetting. Since the lateral prefrontal cortex is thought to mediate motivated forgetting by exerting top-down control over the brain structures that underpin memory representations, the present study aimed to test the hypothesis that selective directed forgetting is prefrontally driven. Specifically, we used transcranial direct current stimulation to disrupt activity in the dorsolateral prefrontal cortex, using a stimulation protocol that has already been shown to be effective in this regard. Our results reveal that, in contrast to sham stimulation, real stimulation abolished selective directed forgetting. Additionally, real stimulation hindered performance in an updating working memory task thought to recruit the lateral prefrontal cortex. These findings, complementing others obtained with a variety of memory control tasks, support the hypothesis that memory downregulation is achieved by control processes mediated by the right lateral prefrontal cortex.