Preventing interference between different memory tasks

Abstract

Learning both a word list and a motor memory task in a short interval usually leads to interference between the two tasks, resulting in poorer performance. Depending on the order of the tasks, the authors were able to directly prevent interference by applying transcranial magnetic stimulation to disrupt processing in either the prefrontal or the motor cortex, which suggests that distinct mechanisms underlie memory interference. When learned in quick succession, declarative and motor skill tasks interfere with one another and subsequent recall is impaired. Depending on the order of the tasks, we were able to prevent memory interference in humans by applying transcranial magnetic stimulation to either the dorsolateral prefrontal or the primary motor cortex, and neither memory was impaired. Our observations suggest that distinct mechanisms support the communication between different types of memory processing.