Spatial biases in graphomotor production tasks such as figure drawing may reflect biological (cerebral lateralization), biomechanical (limb movement), and/or cultural (reading/writing direction) influences. The present study examined sources of bias in the placement in graphic space of a symmetrical drawn figure (a tree). A previous study using a child sample found an overall leftward placement bias, independent of participants’ reading/writing direction experience [Picard & Zarhbouch, 2014. Leftward spatial bias in children's drawing placement: Hemispheric activation versus directional hypotheses. Laterality: Asymmetries of Body, Brain and Cognition, 19(1), 96–112]; moreover, the left-side bias was greater in right handers. Using an adult sample, the present study also found an overall left placement bias. This effect was significantly greater in right-handed than left-handed participants. Importantly, a left placement bias was significantly greater in left-to-right readers (English) than in participants whose first learned language was from right-to-left (Urdu, Arabic or Farsi). The fact that script directionality is associated with figure placement in our study but not in the previous study suggests that a certain threshold of experience in reading/writing in a given direction may be needed for scanning biases to exert a demonstrable effect on representational drawing. These findings suggest that biomechanical and cultural factors offer a more parsimonious account of spatial biases in drawing.

绘图运动产生任务中的空间偏差（例如图形绘制）可能反映了生物学（大脑侧向化），生物力学（肢体运动）和/或文化（读/写方向）的影响。本研究检查了对称绘制图形（树）在图形空间中的位置偏差的来源。先前使用儿童样本进行的研究发现，与参与者的阅读/书写方向经验无关，总体上是向左放置的偏差[Picard＆Zarhbouch，2014。儿童绘画放置中的向左空间偏差：半球激活与方向性假设。横向：身体，大脑和认知的不对称性，19（1），96-112]；此外，右撇子的偏见更大。使用成人样本，本研究还发现了总体左侧放置偏倚。右撇子参与者的这种效果明显大于左撇子参与者。重要的是，从左向右阅读器（英语）的左置偏向要明显比从右向左学习第一语言（乌尔都语，阿拉伯语或波斯语）的参与者大。在我们的研究中，脚本的方向性与图形放置有关，而在先前的研究中却没有，这一事实表明，可能需要一定的经验阈值才能在给定方向上进行读/写操作，以扫描偏见，从而对代表性图形产生明显的影响。这些发现表明，生物力学和文化因素对绘画中的空间偏差提供了更为简约的解释。