PDF(Pubmed)
Abstract：
BACKGROUND: An intronic deletion within intron 2 of the DCDC2 gene encompassing the entire READ1 (hereafter, READ1d) has been associated in both children with developmental dyslexia (DD) and typical readers (TRs), with interindividual variation in reading performance and motion perception as well as with structural and functional brain alterations. Visual motion perception -- specifically processed by the magnocellular (M) stream -- has been reported to be a solid and reliable endophenotype of DD. Hence, we predicted that READ1d should affect neural activations in brain regions sensitive to M stream demands as reading proficiency changes.
METHODS: We investigated neural activations during two M-eliciting fMRI visual tasks (full-field sinusoidal gratings controlled for spatial and temporal frequencies and luminance contrast, and sensitivity to motion coherence at 6%, 15% and 40% dot coherence levels) in four subject groups: children with DD with/without READ1d, and TRs with/without READ1d.
RESULTS: At the Bonferroni-corrected level of significance, reading skills showed a significant effect in the right polar frontal cortex during the full-field sinusoidal gratings-M task. Regardless of the presence/absence of the READ1d, subjects with poor reading proficiency showed hyperactivation in this region of interest (ROI) compared to subjects with better reading scores. Moreover, a significant interaction was found between READ1d and reading performance in the left frontal opercular area 4 during the 15% coherent motion sensitivity task. Among subjects with poor reading performance, neural activation in this ROI during this specific task was higher for subjects without READ1d than for READ1d carriers. The difference vanished as reading skills increased.
CONCLUSIONS: Our findings showed a READ1d-moderated genetic vulnerability to alterations in neural activation in the ventral attentive and salient networks during the processing of relevant stimuli in subjects with poor reading proficiency.
METHODS: We investigated neural activations during two M-eliciting fMRI visual tasks (full-field sinusoidal gratings controlled for spatial and temporal frequencies and luminance contrast, and sensitivity to motion coherence at 6%, 15% and 40% dot coherence levels) in four subject groups: children with DD with/without READ1d, and TRs with/without READ1d.
RESULTS: At the Bonferroni-corrected level of significance, reading skills showed a significant effect in the right polar frontal cortex during the full-field sinusoidal gratings-M task. Regardless of the presence/absence of the READ1d, subjects with poor reading proficiency showed hyperactivation in this region of interest (ROI) compared to subjects with better reading scores. Moreover, a significant interaction was found between READ1d and reading performance in the left frontal opercular area 4 during the 15% coherent motion sensitivity task. Among subjects with poor reading performance, neural activation in this ROI during this specific task was higher for subjects without READ1d than for READ1d carriers. The difference vanished as reading skills increased.
CONCLUSIONS: Our findings showed a READ1d-moderated genetic vulnerability to alterations in neural activation in the ventral attentive and salient networks during the processing of relevant stimuli in subjects with poor reading proficiency.
摘要：
背景：DCDC2基因内含子2内的内含子缺失，包含整个READ1（以下，READ1d）在患有发育性阅读障碍（DD）和典型读者（TR）的儿童中都有关联，在阅读表现和运动知觉以及大脑结构和功能改变方面具有个体差异。据报道，视觉运动知觉-特别是由大细胞（M）流处理-是DD的可靠且可靠的内表型。因此，我们预测，随着阅读能力的变化，READ1d会影响对M流需求敏感的大脑区域的神经激活。
方法：我们研究了两个M-elicitingfMRI视觉任务（控制时空频率和亮度对比的全场正弦光栅，对运动相干性的敏感度为6%，15％和40％点一致性水平）在四个主题组中：有/没有READ1d的DD儿童，和TRs有/没有READ1d。
结果：在Bonferroni校正的显著性水平上，在全场正弦光栅-M任务中，阅读技能在右极额叶皮层中显示出显着影响。无论是否存在READ1d，与阅读得分较高的受试者相比,阅读能力较差的受试者在该感兴趣区域(ROI)表现出超激活.此外，在15%的相干运动敏感度任务中,发现READ1d与左额叶手术区4的阅读表现之间存在显著的交互作用.在阅读表现不佳的科目中，在此特定任务期间,无READ1d的受试者的ROI神经激活高于READ1d携带者.随着阅读技能的提高，这种差异消失了。
结论：我们的研究结果表明，在阅读能力较差的受试者中，在处理相关刺激的过程中，腹侧注意力和显著网络中神经激活的改变具有READ1d调节的遗传脆弱性。
方法：我们研究了两个M-elicitingfMRI视觉任务（控制时空频率和亮度对比的全场正弦光栅，对运动相干性的敏感度为6%，15％和40％点一致性水平）在四个主题组中：有/没有READ1d的DD儿童，和TRs有/没有READ1d。
结果：在Bonferroni校正的显著性水平上，在全场正弦光栅-M任务中，阅读技能在右极额叶皮层中显示出显着影响。无论是否存在READ1d，与阅读得分较高的受试者相比,阅读能力较差的受试者在该感兴趣区域(ROI)表现出超激活.此外，在15%的相干运动敏感度任务中,发现READ1d与左额叶手术区4的阅读表现之间存在显著的交互作用.在阅读表现不佳的科目中，在此特定任务期间,无READ1d的受试者的ROI神经激活高于READ1d携带者.随着阅读技能的提高，这种差异消失了。
结论：我们的研究结果表明，在阅读能力较差的受试者中，在处理相关刺激的过程中，腹侧注意力和显著网络中神经激活的改变具有READ1d调节的遗传脆弱性。
