The learning theory argues that attachments are based on the principles of operant and classical conditioning. First attachments are quite often formed to the person who looks after the child, who feeds them, changes their nappies and comforts them. First attachment figures are a powerful source of pleasure for the baby, as well as removing physical and emotional discomforts including pain, cold and hunger. An early version of the learning theory based on both operant and classical conditioning was proposed by Dollard and Miller (1950)

According to the learning theory, the baby has to learn to form an attachment with his/her caregiver. In the process of operant conditioning, the caregiver rewards the baby by feeding it, so the baby then associates the caregiver with the reward and repeats any action that brings her close. This happens because food brings a feeling of pleasure to the baby. Food is the primary reinforcer. By removing discomfort, it reinforces the behaviour that led to its arrival. But food doesn't come without the caregiver bringing it, so the caregiver becomes the secondary reinforcer - even without bringing food, the presence or the mother reduces discomfort and brings a feeling of pleasure. The baby will therefore repeat any action, for example, crying which brings the caregiver close.

On the other hand, classical conditioning argues that attachment is learnt by association. According to classical conditioning, food is an unconditioned stimulus that produces an unconditioned response (pleasure). At the outset, the caregiver is a neutral stimulus who produces no response. However, because the caregiver is continually paired with the unconditioned stimulus (food), she slowly becomes associated with it until eventually the mother/caregiver alone can produce pleasure. The mother then becomes a conditioned stimulus and the pleasure she brings is a