Research at the University of Sheffield has demonstrated how a child´s perception of shaded pictures becomes increasingly more rigid as they mature, due to changes in the way their brains interpret light on an image.

The research looked at how perception in children changes as they develop, based on the idea that although perception of a shaded picture is inherently ambiguous, this ambiguity can be resolved if the brain assumes that light comes from a specific direction. The findings of the research are soon to be published in the journal Perception.

Using naturalistic pictures (such as a picture of footprints in the sand), Dr Jim Stone from the University´s Department of Psychology, and Dr Olivier Pascalis from the Université Pierre Mendes France in Grenoble, tested 171 children between the ages of four and 11 years, and found that, in contrast to adults, children´s perceptions about where the light appears to come from seem to be much less rigid and hence their interpretation of the picture varied.

For an adult, perception is dominated by the assumption that light comes from above, ensuring that most adults would experience the illusion that the footprints are sticking out of the sand. This same assumption ensures that turning this picture upside-down usually results in the footprints looking `normal´. In contrast, the research showed that children are capable of perceiving both the upright and inverted versions of the picture as normal footprints.

However, as they grow older, children´s perceptions of pictures like this become more adult-like, as if children increasingly adopt the assumption that light comes from above.

Whilst previous research has found this to be the case using abstract symbols, Dr Stone and Dr Pascalis found that this result also holds true for naturalistic pictures, such as photographs.

Crucially, the results from Dr Stone and Dr Pascalis´ research show that, at any given age, children are more likely to perceive naturalistic pictures in an adult-like manner. This suggests that the abstract pictures used in previous studies may have led to an over-estimation of when children begin to acquire an assumption that light comes from above. As a result, the current estimates of between 9-21 months may be driven downwards by the use of more realistic pictures.

Dr Stone now intends to broaden the scope of this research by investigating if other aspects of perception show a similar developmental path as children grow older.

Dr Jim Stone from the University of Sheffield´s Department of Psychology, said: "This is a neat, unambiguous result. Children really do see the world differently to the way that adults do, inasmuch as their perceptions seem to be more variable. This is probably because children make less rigid assumptions about the world, like whether light is coming from above or below. No wonder they cannot look at a cloud without seeing it as a dog or a bear, whereas adults tend to see a cloud as a cloud."

Researchers shed light on children´s perception

Researchers shed light on children´s perception

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