Rushe T M, Temple C M, Rifkin L, Woodruff P W R, Bullmore E T, Stewart A L, Simmons A, Russell T A, Murray R M
Department of Psychology, University of Ulster at Jordanstown, N Ireland BT37 0QB, UK.
Arch Dis Child Fetal Neonatal Ed. 2004 Mar;89(2):F112-8. doi: 10.1136/adc.2001.005314.
To explore, using functional magnetic resonance imaging (MRI), the functional organisation of phonological processing in young adults born very preterm.
Six right handed male subjects with radiological evidence of thinning of the corpus callosum were selected from a cohort of very preterm subjects. Six normal right handed male volunteers acted as controls.
Blood oxygenation level dependent contrast echoplanar images were acquired over five minutes at 1.5 T while subjects performed the tasks. During the ON condition, subjects were visually presented with pairs of non-words and asked to press a key when a pair of words rhymed (phonological processing). This task alternated with the OFF condition, which required subjects to make letter case judgments of visually presented pairs of consonant letter strings (orthographic processing). Generic brain activation maps were constructed from individual images by sinusoidal regression and non-parametric testing. Between group differences in the mean power of experimental response were identified on a voxel wise basis by analysis of variance.
Compared with controls, the subjects with thinning of the corpus callosum showed significantly reduced power of response in the left hemisphere, including the peristriate cortex and the cerebellum, as well as in the right parietal association area. Significantly increased power of response was observed in the right precentral gyrus and the right supplementary motor area.
The data show evidence of increased frontal and decreased occipital activation in male subjects with neurodevelopmental thinning of the corpus callosum, which may be due to the operation of developmental compensatory mechanisms.
使用功能磁共振成像（MRI）探究极早产儿成年后的语音处理功能组织。
从一组极早产儿中挑选出六名有胼胝体变薄影像学证据的右利手男性受试者。六名正常右利手男性志愿者作为对照。
在1.5T磁场下，受试者执行任务时，采集五分钟的血氧水平依赖对比回波平面图像。在“开启”状态下，向受试者视觉呈现非单词对，要求他们在一对单词押韵时按键（语音处理）。该任务与“关闭”状态交替进行，“关闭”状态要求受试者对视觉呈现的辅音字母串对进行大小写判断（正字法处理）。通过正弦回归和非参数测试从个体图像构建通用脑激活图。通过方差分析在体素水平上确定实验组反应平均功率的组间差异。
与对照组相比，胼胝体变薄的受试者在左半球，包括纹状周皮质和小脑，以及右顶叶联合区的反应功率显著降低。在右中央前回和右辅助运动区观察到反应功率显著增加。
数据显示胼胝体神经发育变薄的男性受试者存在额叶激活增加和枕叶激活减少的证据，这可能是由于发育补偿机制的作用。
