University of Milano-Bicocca and Institute of Molecular Bioimaging and Physiology, Milan, CNR, Italy.
Cogn Neuropsychol. 2006 May 1;23(3):355-75. doi: 10.1080/02643290442000536.
Neuroimaging studies have provided evidence that the orthographic properties of linguistic stimuli are processed within the visual word form area (VWFA) localised in the left inferotemporal cortex (Cohen & Dehaene, 2004). It is not, however, clear in the literature whether this region responds preferentially to words, distinguishing them from pseudowords, or whether the pseudowords are distinguished from letter-strings on the basis of their orthographic regularity, or again, whether the VWFA distinguishes letters from numbers or from visual stimuli such as chequerboards. Very recently, it has been claimed that there is no evidence that the ill-named VWFA changes its responsiveness during or after reading acquisition (Price & Devlin, 2004). In order to simulate a condition of pre-reading ability in adult readers, we performed this study, in which we compared processing of Greek words and legal pseudowords in mother-tongue Greeks (skilled readers) and monolingual Italian individuals (naive readers) who had no familiarity with the Greek alphabet. ERPs were recorded while volunteers were engaged in a task involving the identification and response to target letters contained within Greek words or pseudowords. The response speed was identical in the two groups (550 vs. 557 ms). ERP data showed that at 165 ms post-stimulus (N1 component) the left lateral-occipital scalp area, probably corresponding to the left ventral occipitotemporal sulcus, discriminates letters of a familiar alphabet, while an unknown alphabet also activates the homologous right-hemispheric region more than 100 ms later. This suggests that the VWFA discriminates nonalphabetic symbols from letter-strings. An analysis of the N2 component showed an increase in the activation of the same region at about 285 ms post-stimulus during the processing of words rather than pseudowords in skilled readers, thus supporting the view that the VWFA discriminates words on the basis of their familiarity. The data seem to suggest that the VWFA is alphabet-specific and that it is based on the shaping of visual area activity during acquisition of the ability to read a given symbolic code.
神经影像学研究提供了证据，表明语言刺激的正字法属性是在左侧下颞叶皮层（VFA）中处理的，该区域位于左侧下颞叶皮层（Cohen 和 Dehaene，2004）。然而，文献中并不清楚该区域是否优先对单词做出反应，将它们与伪词区分开来，或者伪词是否基于其正字法规则与字母串区分开来，或者再次，VFA 是否区分字母和数字或视觉刺激，如棋盘。最近，有人声称没有证据表明命名不当的 VFA 在阅读获得期间或之后改变其反应性（Price 和 Devlin，2004）。为了模拟成年读者的阅读前能力条件，我们进行了这项研究，比较了母语为希腊语的熟练读者和不熟悉希腊字母的单语意大利个体（新手读者）对希腊语单词和合法伪词的处理。志愿者在参与一项涉及识别和响应包含在希腊语单词或伪词中的目标字母的任务时记录了 ERP。两组的反应速度相同（550 与 557 毫秒）。ERP 数据显示，在刺激后 165 毫秒（N1 成分），左侧外侧枕叶头皮区域，可能对应于左侧腹侧枕颞沟，区分熟悉字母表的字母，而未知字母表在 100 毫秒后也更激活同源右半球区域。这表明 VFA 区分非字母符号和字母串。对 N2 成分的分析表明，在熟练读者处理单词而不是伪词时，在刺激后约 285 毫秒，同一区域的激活增加，从而支持 VFA 根据其熟悉程度区分单词的观点。数据似乎表明，VFA 是字母特定的，它是基于在获得阅读特定符号代码能力的过程中对视觉区域活动的塑造。
