Abstract
When we cannot recall the name of a well-known person despite preserved access to his/her semantic knowledge, a phonological hint such as the initials sometimes helps us to recall. Such recall failure appeared to occur by the transmission deficit from lexical-semantic to lexical-phonological stages in recall processes, and the phonological cue appeared to activate the transmission, leading to successful recall. Using event-related fMRI, we investigated brain regions that respond to the phonological cue. Eighteen right-handed subjects participated in this study. Written informed consent was obtained from all the subjects in accordance with Declaration of Helsinki, and the experimental procedures were approved by the Institutional Review Board of National Institute of Radiological Sciences. We used a 3T MRI system (Signa EXCITE, GE) with GE-EPI. A famous face image was presented with a phonological cue and subjects were required to overtly pronounce the name. The number of correctly recalled trials with first syllable (F) was larger than those with non-verbal sound of a chime (C) and non-first syllable (NF), suggesting that F facilitated name recall. The fMRI results demonstrated that two regions in the left superior temporal gyrus responded more to F than C and NF. In addition, they responded more to the successful recall. These results suggest that they may play a crucial role in the transmission from lexical-semantic to lexical-phonological stages in name recall processes. [J Physiol Sci. 2008;58 Suppl:S144]
