Unidad de Investigación en Neurodesarrollo Dr Augusto Fernández Guardiola, Departamento de Neurobiología Conductual y Cognitiva, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Querétaro, México.
PLoS One. 2013 Jul 26;8(7):e69837. doi: 10.1371/journal.pone.0069837. Print 2013.
Periventricular Leukomalacia (PVL) affects white matter, but grey matter injuries have also been reported, particularly in the dorsomedial nucleus and the cortex. Both structures have been related to working memory (WM) processes. The aim of this study was to compare behavioral performances and EEG power spectra during a visuospatial working memory task (VSWMT) of toddlers with a history of PVL and healthy toddlers.
METHODOLOGY/PRINCIPAL FINDINGS: A prospective, comparative study of WM was conducted in toddlers with a history of PVL and healthy toddlers. The task responses and the EEG narrow-band power spectra during a VSWMT were compared in both groups. The EEG absolute power was analyzed during the following three conditions: baseline, attention and WM retention. The number of correct responses was higher in the healthy group (20.5 ± 5.0) compared to the PVL group (16.1 ± 3.9) (p = 0.04). The healthy group had absolute power EEG increases (p ≤ 0.05) during WM compared to the attention condition in the bilateral frontal and right temporal, parietal and occipital regions in frequencies ranging from 1.17 to 2.34 Hz and in the right temporal, parietal and occipital regions in frequencies ranging from 14.06 to 15.23 Hz. In contrast, the PVL group had absolute power increases (p ≤ 0.05) in the bilateral fronto-parietal, left central and occipital regions in frequencies that ranged from 1.17 to 3.52 Hz and in the bilateral frontal and right temporal regions in frequencies ranging from 9.37 to 19.14 Hz.
CONCLUSIONS/SIGNIFICANCE: This study provides evidence that PVL toddlers have visuospatial WM deficits and a very different pattern of absolute power increases compared to a healthy group of toddlers, with greater absolute power in the low frequency range and widespread neuronal networks in the WM retention phase.
脑室周围白质软化症（PVL）影响白质，但也有报道称灰质损伤，特别是在背内侧核和皮质。这两种结构都与工作记忆（WM）过程有关。本研究旨在比较有 PVL 病史的幼儿和健康幼儿在视空间工作记忆任务（VSWMT）中的行为表现和脑电图功率谱。
方法/主要发现：对有 PVL 病史的幼儿和健康幼儿进行了 WM 的前瞻性、对照研究。比较了两组在 VSWMT 中的任务反应和脑电图窄带功率谱。在以下三种情况下分析了 EEG 绝对功率：基线、注意力和 WM 保持。健康组的正确反应数（20.5±5.0）高于 PVL 组（16.1±3.9）（p=0.04）。与注意力条件相比，健康组在 WM 期间双侧额区和右侧颞区、顶区和枕区的频率范围为 1.17 至 2.34 Hz，右侧颞区、顶区和枕区的频率范围为 14.06 至 15.23 Hz，EEG 绝对功率增加（p≤0.05）。相比之下，PVL 组在双侧额顶、左侧中央和枕区的频率范围为 1.17 至 3.52 Hz，双侧额区和右侧颞区的频率范围为 9.37 至 19.14 Hz，EEG 绝对功率增加（p≤0.05）。
结论/意义：本研究表明，PVL 幼儿存在视空间 WM 缺陷，且与健康幼儿相比，绝对功率增加模式非常不同，在 WM 保持阶段低频范围内的绝对功率增加更大，且涉及更广泛的神经元网络。
