Recognition of Familiar Faces and Scenes in Patients with Very Mild Alzheimer's Disease: An Event-Related Potential Study

• Main Authors: Pei-Ju Cheng, 鄭珮汝
• Other Authors: Ming-chyi Pai
• Format: Others
• Language: zh-TW
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/92904710046146820789

碩士 === 國立成功大學 === 行為醫學研究所 === 97 === Background and objective Besides amnesia and other cognitive dysfunctions, getting lost and inability to recognize people are common in patients with AD, even in the early part of the disease. Based on the fact that the brain regions responsible for face and scene recognition are overlapped, we used ERP to examine whether the deterioration in the recognition of familiar faces and scenes is unparallel in patients with very mild AD. Methods The visual stimulate used for ERP included pictures of familiar faces, novel faces, familiar scenes and novel scenes. Participants were asked to make a judgment if the picture displayed was familiar or not. We recorded their behavioral responses as well as electrophysiological signal at the same time. We focused on N170, reflecting the structural encoding process, and N250r which reflects the stored representation and the familiarity. Results 20 very mild AD patients and 17 normal controls completed the study. The largest N170 waves to FACES come from P7 and P8, while the largest N170 waves to SCENES are from P3 and P4, at which NC produced larger N170 than the AD group. In addition, participants had similar errors rate when judging pictures of faces and scenes as familiar or not, but failed to be detected the familiarity effect in AD patients from the N250r when familiar scenes were provided. Conclusion The study clearly demonstrates that different neural regions are responsible for early visual process in the structure encoding of scenes and faces. As compared with face recognition, scene recognition is impaired earlier in the course of AD.