Schwizer Ashkenazi Simone, McCaskey Ursina, O'Gorman Tuura Ruth, Kucian Karin
Center for MR-Research, University Children's Hospital Zurich, Zurich, Switzerland.
Neuropsychology, Department of Psychology, University of Zurich, Zurich, Switzerland.
J Neurosci Res. 2025 Jul;103(7):e70066. doi: 10.1002/jnr.70066.
Numerical-order ability, a strong predictor of arithmetic, is often impaired in children with developmental dyscalculia (DD). While previous research has shown altered brain responses in number-processing regions in DD compared to typically developing children (TD), little is known about how these regions interact during number processing. This exploratory study examined the effective connectivity between six regions in the right parietal, frontal, and insular cortex as well as the vermis, using dynamic causal modeling (DCM). We investigated how number-order and number-identification tasks modulate connectivity within this network and the group differences related to DD. The number-order task led primarily to increased excitatory connectivity from the pre-supplementary motor area (preSMA) to all other regions, indicating an orchestrating role of the preSMA. DD, who exhibited deficits in number-order performance, demonstrated aberrant modulation of incoming connectivity to the ventral premotor cortex (vPMC) from the anterior intraparietal sulcus (aIPS), the preSMA, and the dorsal anterior insula (d-aINS). In TD, number-identification led to inhibitory modulation from the vPMC to the aIPS and the vermis. While behavioral performance in number-identification was unimpaired in DD, they showed increased excitatory connectivity from dorsal and ventral PMC to the d-aINS and from vPMC to the aIPS. Our results imply that, for both impaired and unimpaired number-related behavioral performance, neuronal number processing differs between DD and TD. This conclusion is further supported by the high predictive validity of the modulating connectivity group-effect parameters. We suggest the underlying explanation for this pattern may be related to decreased acuity of neuronal number representation in DD.
数字顺序能力是算术能力的一个强有力预测指标，在发育性计算障碍（DD）儿童中常常受损。虽然先前的研究表明，与发育正常的儿童（TD）相比，DD儿童在数字处理区域的大脑反应有所改变，但对于这些区域在数字处理过程中如何相互作用却知之甚少。这项探索性研究使用动态因果模型（DCM）研究了右侧顶叶、额叶和岛叶皮质以及蚓部六个区域之间的有效连接。我们研究了数字顺序和数字识别任务如何调节该网络内的连接以及与DD相关的组间差异。数字顺序任务主要导致从辅助运动前区（preSMA）到所有其他区域的兴奋性连接增加，表明preSMA起到了协调作用。在数字顺序表现上存在缺陷的DD儿童，其从前顶内沟（aIPS）、preSMA和背侧前岛叶（d-aINS）到腹侧运动前皮质（vPMC）的传入连接表现出异常调节。在TD儿童中，数字识别导致从vPMC到aIPS和蚓部的抑制性调节。虽然DD儿童在数字识别方面的行为表现未受损，但他们从背侧和腹侧PMC到d-aINS以及从vPMC到aIPS的兴奋性连接增加。我们的结果表明，对于受损和未受损的数字相关行为表现，DD儿童和TD儿童在神经元数字处理方面存在差异。调节连接组效应参数的高预测效度进一步支持了这一结论。我们认为这种模式的潜在解释可能与DD儿童中神经元数字表征的敏锐度降低有关。
