The effect of varying stimulus rate and duration on brain activity during reading

The effect of the presentation rate and exposure duration of visually presented words on brain activity was investigated using positron emission tomography. Subjects either read aloud or silently mouthed the names of words. In regions associated with early visual analysis, activity increased with both rate and duration; in regions associated with response generation, activity increased with increasing rate but was unaffected by duration; and in regions associated with word recognition, activity decreased with increasing duration. The variable responses of different brain regions illustrate the functional segregation of these regions. Of particular interest was the dissociation between activity in the posterior fusiform gyri and that in the medial lingual gyrus--in the former, activity increased with rate and duration but the latter was unaffected by either variable. This finding suggests that word processing in the lingual gyrus during reading is distinct from that in the posterior fusiform gyri. A further observation was that during reading aloud, when subjects can hear the sound of their own voice, the response in the primary auditory cortices increased with stimulus rate, demonstrating that subjects process the sound of their own voice in a qualitatively similar way to words spoken by another.     

光明智能城市一座新型中国城市

截至2010年,预计中国将有一半人口由农村转入城市。中国的经济繁荣促使农民渴望进城一试身手,由此引发了移民大潮。中国政府最近向联合国世界城市论坛展示其新型生态城市——可惜关注的焦点仅仅是能源和环境问题,却忽视了社会和经济等重要因素。可否在农村背景下实现经济快速增长,并阻止农村技术人才流失?如何在保留传统和维持社会可持续性的同时促进农村经济增长?从城市的未来长远发展考虑,必须用新型城市蓝图取代当前的生态城市定义,在城市建设中融入教育、农业、环境及社会可持续性等因素。光明智能城市城镇中心保留了农业传统,并率先将城市规划和生态可持续性融为一体。这一创新型城镇中心将为深圳、中国乃至全世界开辟一种新型城市生活方式。