Ryan Nicholas P, Beauchamp Miriam H, Beare Richard, Coleman Lee, Ditchfield Michael, Kean Michael, Silk Timothy J, Genc Sila, Catroppa Cathy, Anderson Vicki A
Australian Centre for Child Neuropsychological Studies, Murdoch Childrens Research Institute, Melbourne, Australia; Melbourne School of Psychological Sciences, University of Melbourne, Melbourne, Australia; Department of Psychology, Royal Children's Hospital, Melbourne, Australia.
Department of Psychology, University of Montreal, Montreal, Canada; Ste-Justine Research Center, Montreal, Canada.
Cortex. 2016 Oct;83:222-30. doi: 10.1016/j.cortex.2016.07.020. Epub 2016 Aug 16.
Cognitive fatigue is among the most profound and disabling sequelae of pediatric acquired brain disorders, however the neural correlates of these symptoms in children remains unexplored. One hypothesis suggests that cognitive fatigue may arise from dysfunction of cortico-striatal networks (CSNs) implicated in effort output and outcome valuation. Using pediatric traumatic brain injury (TBI) as a model, this study investigated (i) the sub-acute effect of brain injury on CSN volume; and (ii) potential relationships between cognitive fatigue and sub-acute volumetric abnormalities of the CSN. 3D T1 weighted magnetic resonance imaging sequences were acquired sub-acutely in 137 children (TBI: n = 103; typically developing - TD children: n = 34). 67 of the original 137 participants (49%) completed measures of cognitive fatigue and psychological functioning at 24-months post-injury. Results showed that compared to TD controls and children with milder injuries, children with severe TBI showed volumetric reductions in the overall CSN package, as well as regional gray matter volumetric change in cortical and subcortical regions of the CSN. Significantly greater cognitive fatigue in the TBI patients was associated with volumetric reductions in the CSN and its putative hub regions, even after adjusting for injury severity, socioeconomic status (SES) and depression. In the first study to evaluate prospective neuroanatomical correlates of cognitive fatigue in pediatric acquired brain disorder, these findings suggest that post-injury cognitive fatigue is related to structural abnormalities of cortico-striatal brain networks implicated in effort output and outcome valuation. Morphometric magnetic resonance imaging (MRI) may have potential to unlock early prognostic markers that may assist to identify children at elevated risk for cognitive fatigue post-TBI.
认知疲劳是小儿后天性脑疾病最严重且致残的后遗症之一，然而儿童这些症状的神经关联仍未得到探索。一种假说认为，认知疲劳可能源于参与努力输出和结果评估的皮质-纹状体网络（CSNs）功能失调。本研究以小儿创伤性脑损伤（TBI）为模型，调查了（i）脑损伤对CSN体积的亚急性影响；以及（ii）认知疲劳与CSN亚急性体积异常之间的潜在关系。对137名儿童进行了亚急性3D T1加权磁共振成像序列扫描（TBI组：n = 103；正常发育儿童——TD组：n = 34）。在最初的137名参与者中，67名（49%）在受伤后24个月完成了认知疲劳和心理功能测量。结果显示，与TD对照组和轻伤儿童相比，重度TBI儿童的整个CSN总体积减少，以及CSN皮质和皮质下区域的灰质体积发生区域性变化。即使在调整了损伤严重程度、社会经济地位（SES）和抑郁因素后，TBI患者中明显更严重的认知疲劳仍与CSN及其假定枢纽区域的体积减少有关。在第一项评估小儿后天性脑疾病中认知疲劳的前瞻性神经解剖学关联的研究中，这些发现表明，受伤后的认知疲劳与参与努力输出和结果评估的皮质-纹状体脑网络的结构异常有关。形态计量磁共振成像（MRI）可能有潜力揭示早期预后标志物，有助于识别TBI后认知疲劳风险较高的儿童。
