Psychology is known to everyone of us as the most interesting topic of study, no doubt. Irrespective of whether you like kids or not, and if you (really) think kids are fun to be with, the study of child psychology is interesting for sure. As an inherent field of psychology, it lets you question every little aspect of 'why' you are the way you are. There are umpteen number of things you wouldn't believe that have influenced our 'growing-up'. Like several such exciting topics studying how we grow up to be an adult, here is one that tells us how we come to know that things around us exist, as objects. Developmental psychology studies transitions in human life (infants - children - adolescents - adults) in a scientific manner. This field of psychology, initially, concerned the study of infants and children only. The inclusion of the adolescent and adult stage was an expansion of the original scope of study. On this background, the phenomenon of object permanence is a fundamental concept in developmental psychology. Object permanence refers to the fact that objects do exist even if they cannot be observed or experienced through the senses (touched, seen, smelled, or heard). A Swiss psychologist named Jean Piaget is known to be the pioneer in this academic arena, who studied object permanence in infants, and perceived it to be a very significant skill attained by them. He conducted some experiments that were based on the behavioral responses of infants; actually, he is believed to have experimented and noted observations from the behavior of his own kids. In one such experiment, a toddler was first shown a toy (or a favorite object), and later, it was covered up with a blanket, or taken out of his sight. The child's reaction to this was observed by him. This classic experiment is done even today. If the infant tries to reach for that hidden toy, or pull that blanket away from the toy, it indicates that he/she has begin to develop object permanence. On the contrary, if the infant seems confused, it shows he/she has not yet developed it. This experiment, besides studying object permanence, also measures working memory. If you are wondering 'Is peek-a-boo an example of object permanence', then you have certainly guessed it right. It is one of the first acts of play that you introduce your child to. Infants and toddlers enjoy it, alike. Through this fun activity, it can be determined whether the baby shows any signs of 'object permanence' understanding. Jean Piaget propounded the theory of cognitive development, which tries to explain the nature and development of human intelligence. He has given the following four stages in the theory: sensorymotor stage, pre-operational stage, concrete operational stage, and formal operational stage. The emergence of object permanence is associated with the first stage, or the sensorymotor stage. It refers to the period approximately from 0 to 2 years, or from birth up to the period of language acquisition. Piaget divides this stage further into six sub-stages according to age and the acquired learning associated with it. Babies learn about their surroundings primarily by coordinating between vision and hearing experiences. Also, physical touch, feel, grasping, and sucking of objects helps them know the objects better. According to Piaget, object permanence is thus, a very important accomplishment for infants at this stage. Perhaps, that is why it is said that kids should be provided with maximum sensory exposures (different textures, sounds, smells, tastes, and visuals) before they turn five. A-not-B error: This differently-named phenomenon, occurring at the 'sub-stage four', indicates the non-development of object permanence. It is when kids habituated to finding their favorite toy under box 'A', search for it in the same place, even after they see the toy being moved under box 'B'. Also known as 'preservation error', this is observed among babies that are 10 months old, or younger. He has also concluded that some are just too young for this skill. This, he exemplifies by the common observation of infants not crying when their mothers are not present (out of sight). It should not surprise us to know that monkeys are found to be good at tracing displacement of hidden targets. But there are other animals too who have passed the tests by displaying object permanence. Dogs, being intelligent animals, form part of the group, which also includes cats and a few bird species (carrion crow and magpies). The targets are usually kept hidden and rotated at certain degrees while testing with some animals. Studies have also found the carrion crow to attain a similar level of object permanence as humans. So while wondering about your toddler's development, don't think that they are too young for it. Like they say, it is between 0 and 5 years that your little ones have the maximum power to grasp, which enhances their intelligence permanently.