State Key laboratory of Cognitive Neuroscience and Learning, Beijing Normal University, China.
Neuroimage. 2011 Apr 1;55(3):1346-56. doi: 10.1016/j.neuroimage.2010.12.062. Epub 2011 Jan 7.
Although its precise functional contribution to reading remains unclear, there is broad consensus that an activity in the left mid-fusiform gyrus is highly sensitive to written words and word-like stimuli. In the current study, we take advantage of a particularity of the Chinese writing system in order to manipulate word-likeness parametrically, from real characters, to pseudo-characters that vary in whether they contain phonological and semantic cues, to artificial stimuli with varying surface similarity to real characters. In a one-back task, BOLD activity in the left mid-fusiform was inversely related to word-likeness, such that the least activity was observed in response to real characters, and the greatest to artificial stimuli that violate the orthotactic constraints of the writing system. One possible explanation for this surprising result is that the short-term memory demands of the one-back task put more pressure on the visual system when other sources of information cannot be used to aid in detecting repeated stimuli. For real characters and, to a lesser extent for pseudo-characters, information about meaning and pronunciation can contribute to performance, whereas artificial stimuli are entirely dependent on visual information. Consistent with this view, functional connectivity analyses revealed a strong positive relationship between left mid-fusiform and other visual areas, whereas areas typically involved in phonological and semantic processing for text were negatively correlated with this region.
尽管其对阅读的精确功能贡献仍不清楚，但人们普遍认为左中梭状回的活动对书面文字和类文字刺激高度敏感。在当前的研究中，我们利用了中文书写系统的一个特点，以便参数化地操纵类文字的相似度，从真实的字符到包含语音和语义线索的伪字符，再到与真实字符具有不同表面相似度的人工刺激。在一项 1 -back 任务中，左中梭状回的 BOLD 活动与类文字相似度呈负相关，因此对真实字符的反应活性最低，对违反书写系统正字法约束的人工刺激的反应活性最高。对于这个令人惊讶的结果，一种可能的解释是，1-back 任务的短期记忆需求给视觉系统带来了更大的压力，因为无法利用其他信息来源来帮助检测重复的刺激。对于真实字符，并且在较小程度上对于伪字符，关于意义和发音的信息可以有助于提高性能，而人工刺激则完全依赖于视觉信息。与这一观点一致的是，功能连接分析显示左中梭状回与其他视觉区域之间存在强烈的正相关关系，而通常与文字的语音和语义处理相关的区域与该区域呈负相关。
