Iidaka Tetsuya, Okada Tomohisa, Murata Tetsuhito, Omori Masao, Kosaka Hirotaka, Sadato Norihiro, Yonekura Yoshiharu
Biomedical Imaging Research Center, Fukui Medical University, Japan.
Hippocampus. 2002;12(3):352-62. doi: 10.1002/hipo.1113.
Age-related differences involved in the neural substrates of emotional face perception were investigated in young and old healthy volunteers. The subjects were scanned using functional magnetic resonance imaging while they were judging the gender of faces with negative, positive, or neutral emotional valence. The results showed that both the predominant activation in young subjects and reduced activity in old subjects contributed to a significant age difference in the left amygdala during the perception of negative faces. Activity in the right parahippocampal gyrus during the perception of positive faces diminished with advancing age. Neural activity in the angular gyrus and lingual gyrus of the right hemisphere was reduced in the old subjects during the perception of positive faces. There was no region where old subjects had greater activity than young subjects during the task. In old subjects, the overall activity in the right hippocampus during the task correlated negatively with age, whereas the activity in the right parahippocampal gyrus correlated positively with neuropsychological performance. There was no significant correlation between subjects' characteristics and signal change in young subjects. These results indicate the age-associated vulnerability of the medial temporal lobe structures including the amygdala, hippocampus, and parahippocampal gyrus during face perception. The dissociation with reduced activity in the left amygdala and the right parahippocampal gyrus may suggest that aging differentially affects neural responses to faces with negative or positive emotional valence. The parieto-occipital lobe, which has been found to be involved in face processing, also showed a functional decline associated with aging.
在年轻和年长的健康志愿者中，研究了与情绪面孔感知的神经基质相关的年龄差异。在受试者判断具有负面、正面或中性情绪效价的面孔性别时，使用功能磁共振成像对他们进行扫描。结果显示，在感知负面面孔期间，年轻受试者的主要激活和年长受试者的活动减少，共同导致了左杏仁核的显著年龄差异。在感知正面面孔期间，右侧海马旁回的活动随着年龄的增长而减弱。在感知正面面孔期间，年长受试者右半球角回和舌回的神经活动减少。在任务过程中，没有区域年长受试者的活动比年轻受试者更强。在年长受试者中，任务期间右侧海马的整体活动与年龄呈负相关，而右侧海马旁回的活动与神经心理表现呈正相关。年轻受试者的特征与信号变化之间没有显著相关性。这些结果表明，在面孔感知过程中，包括杏仁核、海马和海马旁回在内的内侧颞叶结构存在与年龄相关的易损性。左杏仁核和右侧海马旁回活动减少的分离可能表明，衰老对面孔具有负面或正面情绪效价的神经反应有不同影响。已发现参与面孔处理的顶枕叶也显示出与衰老相关的功能衰退。
