Early precursors to theory of mind: Infant understanding of the referential nature of visual perception

In an attempt to locate early precursors of theory of mind, investigators have examined infant comprehension of perception, specifically whether infants understand seeing as a referential act with an external attentional focus or simply as a behavioral event involving orientation of the head and eyes. Relevant research has focused on the phenomenon of joint visual attention (looking where someone else is looking) which emerges around 12 months and can be interpreted either mentally (wanting to see what someone else is seeing) or behaviorally (using adult turns as learned predictive cues for the location of interesting events).;The current study was intended to provide a test of the two positions. In two experiments the joint visual attention of 114, 14- and 18-month-olds were examined under varying visual obstruction conditions: (a) when the adult's line of gaze to remote targets was blocked by opaque screens (screen condition), (b) when the screens were folded back and no longer obstructed the adult's view (no-screen condition), and (c) when the screen contained a window to allow viewing of the targets (window condition).;It was assumed that infants who use adult head turns as predictive cues would turn equally in all three conditions but that infants who comprehend the referential nature of seeing would turn maximally in the no-screen and window conditions, and minimally in the screen condition. In accord with the referential position, 18-month-olds turned equally often in the no-screen and window conditions and exhibited very few turns in the screen condition. On the other hand, the 14-month-old rate of turning declined from the no-screen to the screen condition and turned least in the window condition. The results suggest that 14-month-olds do not comprehend line of sight or the referential nature of vision and that comprehension of the mental nature of seeing emerges sometime between 14 and 18 months.