Asymmetric bias in perception of facial affect among Roman and Arabic script readers
Author: Heath RL, Rouhana A, Ghanem DA.
Source:
Laterality: Asymmetries of Body, Brain, and Cognition, 10(1), 51-64.
The asymmetric chimeric faces test is used frequently as an indicator of right
hemisphere involvement in the perception of facial affect, as the test is
considered free of linguistic elements. Much of the original research with the
asymmetric chimeric faces test was conducted with subjects reading left-to-right
Roman script, i.e., English. As readers of right-to-left scripts, such as Arabic,
demonstrated a mixed or weak rightward bias in judgements of facial affect, the
influence of habitual scanning direction was thought to intersect with
laterality. We administered the asymmetric chimeric faces test to 1239 adults who
represented a range of script experience, i.e., Roman script readers (English and
French), Arabic readers, bidirectional readers of Roman and Arabic scripts, and
illiterates. Our findings supported the hypothesis that the bias in facial affect
judgement is rooted in laterality, but can be influenced by script direction.
Specifically, right-handed readers of Roman script demonstrated the greatest mean
leftward score, and mixed-handed Arabic script readers demonstrated the greatest
mean rightward score. Biliterates showed a gradual shift in asymmetric
perception, as their scores fell between those of Roman and Arabic script
readers, basically distributed in the order expected by their handedness and most
often used script. Illiterates, whose only directional influence was laterality,
showed a slight leftward bias.