Object Permanence and Psychology of the Infant

Pediatrics was one of the postings I enjoyed for the stress on sound clinical knowledge and the large variability in presentation of patients.

One of the important aspects of pediatrics even laymen are aware of is “developmental milestones” – we all know that kids are supposed to walk and say their first words around 1 year of age. A recent field of interest is Developmental psychology, which deals with evolution of the human mind as an infant learns about the world. A lot of interesting findings surround these “milestones”: For instance, the A-not-B error.

First a little background – There is a developmental milestone called “Object Permanence”: A young infant is really not aware where objects go when they are hidden from view – the moment the object vanishes from the field of vision, the infant believes that it has disappeared. For example, the infant is shown a toy and he reaches for it – then, while the infant watches, the toy is hidden or removed, and the infant does not understand that the toy still “exists” – to him, it has just “disappeared”.

At some point the infant understands or learns that objects do not disappear when they are covered – this is called object permanence.

However, this psychological concept is learnt slowly by trial and error – creating the classic A-not-B error.

The A-not-B error can be seen in children in the age group of approximately 8-12 months. Here is how to do it. You need two different coloured towels, an attractive toy and of course, the child.

• Show the kid an attractive object.
• Hide it under one towel.
• Prompt the child – if he has progressed to the stage of basic object permanence, he will uncover the towel and get the toy.
• Repeat the experiment, this time, first hiding the object under the original towel, then, while the child watches, move it under the other towel (in plain sight of the child).
• Watch the child make the mistake of searching under the first towel.

Here are a couple of interesting videos about the phenomenon with two demonstrations of the experiment.

Educational video

A mother trying it on her daughter – this experiment may not have been perfect – but the child is obsessed with the first cloth.

The theories behind the experiment are controversial – as are all psychological theories.