Previous neuropsychological studies that investigated patients with brain injury have revealed the presense of multiple memory systems and the related brain regions. Recent functional imaging studies have identified a neuronal network including the temporal cortex and hippocampus that is responsible for the retrieval of semantic memory. This memory network was further investigated by electrophysiology using a simultaneous recording technique. This new technique revealed that a coupling of inter-area top-down signal within the temporal cortex with translaminar signal processing is required for successful memory retrieval of visual objects.