Saj A, Heiz J, Barisnikov K
Department of Neurology, Neuropsychology Unit, University Hospital of Geneva, Switzerland.
Department of Psychology, Child Clinical Neuropsychology Unit, University of Geneva, Switzerland.
J Intellect Disabil Res. 2017 May;61(5):512-518. doi: 10.1111/jir.12358. Epub 2017 Feb 10.
Individuals with Williams Syndrome (WS) are known to have particular difficulties when performing visuo-spatial tasks, which could be related to their difficulties in using a specific reference system to determine spatial relations. The aim of the present study was to assess the internal representation of the body's sagittal plane, which is an important benchmark for an egocentric frame of reference.
The results of 18 WS individuals (mean age = 20.5 ± 9.2 years) on the subjective straight ahead (SSA) task were compared with those of two healthy control groups composed of 36 participants matched on chronological age matched on chronological age (CA) and 30 young children matched on non-verbal intellectual ability (YC).
Individuals with WS showed a significant left deviation on the SSA body's sagittal plane representation compared with the chronological age control group and a marginal left deviation compared with the young children control group. A comparison with the objective SA (0°) showed a significant leftward deviation in the WS group but not in the two control groups.
Individuals with WS showed a significant leftward deviation in the SSA task. This bias of the body's longitudinal axe representation could have a negative impact on the use of an egocentric reference system, which could be the cause for their difficulties in defining spatial relations (e.g. location and orientation) necessary for performing spatial tasks.
已知威廉姆斯综合征（WS）患者在执行视觉空间任务时存在特殊困难，这可能与他们在使用特定参照系确定空间关系方面的困难有关。本研究的目的是评估身体矢状面的内部表征，这是以自我为中心的参照系的一个重要基准。
将18名WS患者（平均年龄 = 20.5 ± 9.2岁）在主观正前方（SSA）任务中的结果与两个健康对照组的结果进行比较，其中一个对照组由36名年龄匹配的参与者组成，另一个对照组由30名非语言智力能力匹配的幼儿组成。
与年龄匹配对照组相比，WS患者在SSA身体矢状面表征上表现出显著的向左偏差，与幼儿对照组相比表现出轻微的向左偏差。与客观矢状面（0°）相比，WS组表现出显著的向左偏差，而两个对照组则没有。
WS患者在SSA任务中表现出显著的向左偏差。身体纵轴表征的这种偏差可能会对以自我为中心的参照系的使用产生负面影响，这可能是他们在定义执行空间任务所需的空间关系（如位置和方向）时遇到困难的原因。
