Investigating via Transcranial Magnetic Stimulation (TMS) the interaction between Visual Short Term Memory (VSTM) and mental imagery in the Early Visual Cortex (EVC)

Visual mental imagery and visual short term memory are often assumed to play similiar roles. There are many evidence showing that they both involve visual cortical neurons which encode incoming sensory information. On the cognitive level it has been explained in terms of the visual cache, which is nvolved in the maintenance of visual short term memory and imagery content. Even though menatl imagery and visual short term memroy may share cogntive resources, they are nevertheless two distinct psychological processes that can be dissociated behaviorally. In this study, we wanted to see if those two processes diverges in early visual cortex. To be able to do it, we used transcranial magnetic stimualtion as a probe of visual cortical activation state. Experiment consists of three diffrent blocks: VSTM alone, mental imagery alone and concurrent VSTM and imagery. The concurrent condition was carried out to understand how imagery and VSTM might interact when they are engaged simultaneously.