Visuo-constructive abilities are a multicomponential process that can be impaired in several neurodegenerative dementias. Among visuo-constructive tasks, the Rey-Osterrieth Complex Figure-copy (ROCF-c) is the most commonly used and it seems influenced by different skills mediated by specific brain regions. This task complexity allows exploring differential mechanisms of impairment in different neurodegenerative disorders. In this study we examined the neuroanatomical substrates of ROCF-c performance in patients with Dementia with Lewy Bodies (DLB) and patients with Alzheimer’s disease (AD). We included forty-five patients with probable DLB, and thirty-four patients with probable typical-AD. To identify the ROCF-c scores neural correlates we performed a regression analysis with brain hypometabolism using the ROCF-c scores as independent variable. Then we evaluated the correlation between regional hypometabolism and ROCF-c scores in each group separately, throughout offline Pearson correlation analysis. The DLB and AD groups differed only in visuo-constructive and memory performances. DLB patients performed worse at the visuo-constructive test, while typical-AD patients performed worse at the verbal memory task. In DLB, worse performance at ROCF-c scores (more severe visuo-constructive impairment) correlated with occipital and temporo-parietal hypometabolism. In AD, worse performance at ROCF-c score was associated with brain hypometabolism in the temporo-parietal regions. The inability to correctly perform the ROCF-c derives from distinct brain dysfunctions in DLB and AD. The present results suggest alterations in visuoperceptual processes due to the severe occipital hypometabolism in DLB, and in visuospatial processes related to temporo-parietal hypometabolism in AD.

视觉建设能力是一个多组分过程，可能在几种神经退行性痴呆中受损。在视觉建设任务中，Rey-Osterrieth Complex Figure-copy (ROCF-c) 是最常用的，它似乎受到特定大脑区域介导的不同技能的影响。这种任务复杂性允许探索不同神经退行性疾病中的不同损伤机制。在这项研究中，我们检查了路易体痴呆 (DLB) 和阿尔茨海默病 (AD) 患者的 ROCF-c 性能的神经解剖学底物。我们纳入了 45 名可能患有 DLB 的患者，以及 34 名可能患有典型 AD 的患者。为了确定 ROCF-c 评分与神经相关性，我们使用 ROCF-c 评分作为自变量对脑低代谢进行了回归分析。然后，我们在离线 Pearson 相关分析中分别评估了每组区域低代谢和 ROCF-c 评分之间的相关性。DLB 和 AD 组仅在视觉建设和记忆表现上有所不同。DLB 患者在视觉建设性测试中表现较差，而典型 AD 患者在语言记忆任务中表现较差。在 DLB 中，ROCF-c 评分的较差表现（更严重的视觉建设性障碍）与枕叶和颞顶叶低代谢相关。在 AD 中，ROCF-c 评分较差的表现与颞顶叶区域的脑代谢低下有关。无法正确执行 ROCF-c 源于 DLB 和 AD 中明显的脑功能障碍。目前的结果表明，由于 DLB 中严重的枕骨低代谢，视觉感知过程的改变，