Reactivation may also be related to the notion that memory relies on the simulation of perception [33], and the more general proposal that memory retrieval involves the reinstatement of cortical activity that occurred during encoding [8].Single-unit recordings in monkeys have provided support for the importance of perceptual reactivation in visual memory [10]. Furthermore, research into conceptual deficits suggests that lesions of specific motor and sensory regions of the brain interfere with knowledge of certain concepts