Chechlacz Magdalena, Novick Abigail, Rotshtein Pia, Bickerton Wai-Ling, Humphreys Glyn W, Demeyere Nele
Oxford University.
J Cogn Neurosci. 2014 Dec;26(12):2701-15. doi: 10.1162/jocn_a_00664. Epub 2014 Jun 4.
Deficits in the ability to draw objects, despite apparently intact perception and motor abilities, are defined as constructional apraxia. Constructional deficits, often diagnosed based on performance on copying complex figures, have been reported in a range of pathologies, perhaps reflecting the contribution of several underlying factors to poor figure drawing. The current study provides a comprehensive analysis of brain-behavior relationships in drawing disorders based on data from a large cohort of subacute stroke patients (n = 358) using whole-brain voxel-wise statistical analyses linked to behavioral measures from a complex figure copy task. We found that (i) overall poor performance on figure copying was associated with subcortical lesions (BG and thalamus), (ii) lateralized deficits with respect to the midline of the viewer were associated with lesions within the posterior parietal lobule, and (iii) spatial positioning errors across the entire figure were associated with lesions within visual processing areas (lingual gyrus and calcarine) and the insula. Furthermore, deficits in reproducing global aspects of form were associated with damage to the right middle temporal gyrus, whereas deficits in representing local features were linked to the left hemisphere lesions within calcarine cortex (extending into the cuneus and precuneus), the insula, and the TPJ. The current study provides strong evidence that impairments in separate cognitive mechanisms (e.g., spatial coding, attention, motor execution, and planning) linked to different brain lesions contribute to poor performance on complex figure copying tasks. The data support the argument that drawing depends on several cognitive processes operating via discrete neuronal networks and that constructional problems as well as hierarchical and spatial representation deficits contribute to poor figure copying.
尽管感知和运动能力看似完好，但绘制物体的能力出现缺陷则被定义为结构性失用症。结构性缺陷通常根据复制复杂图形的表现来诊断，在一系列病症中均有报道，这或许反映了多种潜在因素对图形绘制不佳的影响。本研究基于来自一大群亚急性中风患者（n = 358）的数据，使用全脑体素水平的统计分析，并结合复杂图形复制任务的行为测量结果，对绘图障碍中的脑 - 行为关系进行了全面分析。我们发现：（i）图形复制的总体表现不佳与皮质下病变（基底神经节和丘脑）相关；（ii）相对于观察者中线的偏侧化缺陷与顶叶后小叶内的病变相关；（iii）整个图形的空间定位错误与视觉处理区域（舌回和距状裂）及脑岛内的病变相关。此外，复制形状整体特征的缺陷与右侧颞中回受损有关，而表示局部特征的缺陷与距状皮质（延伸至楔叶和楔前叶）、脑岛及颞顶联合区内的左侧半球病变有关。本研究提供了有力证据，表明与不同脑损伤相关的单独认知机制（如空间编码、注意力、运动执行和计划）受损会导致复杂图形复制任务表现不佳。这些数据支持了这样的观点，即绘图依赖于通过离散神经网络运作的多种认知过程，并且结构性问题以及层次和空间表征缺陷会导致图形复制不佳。
