Differential activation in parahippocampal and prefrontal cortex during word and face encoding tasks

Episodic encoding is the first step in the formation of a memory trace. The relation between type of stimulus material and regional brain activation i s not fully understood. We measured brain activation using fMRI in 12 healt hy subjects during two experiments, word and face encoding. A widespread ne twork of common activations in both tasks was present in the bilateral fron tal (BA44/45), occipital (BA17/18/ 19) and fusiform gyri (BA37) as well as the right hippocampal formation (BA30). A region-of-interest-analysis for t he hippocampal formation and dorsolateral prefrontal cortex (DLPFC) was per formed additionally. During face encoding the right dorsal and during word encoding the bilateral ventral hippocampal region was activated. In the pre frontal cortex a lateralization to the left side was present only for word encoding. During encoding, activation in the inferior frontal and hippocamp al cortex is modulated by the type of stimulus material. NeuroReport 12:277 3-2777 (C) 2001 Lippincott Williams & Wilkins.