What Is the Difference Between a Social Smile & a Reflexive Smile?

If your baby gives you a slight smile after you praise him, you might wonder how he knows to smile when he's too young to understand your words. Reflexive smiles describe a physical action that parents interpret as a smile but happen as a part of normal muscle reflexes. Your child learns to return your smile and show a social smile when he's pleased with his surroundings. These smiles typically happen between 6 and 8 weeks old, according to the American Academy of Pediatrics 2. Smiling is common in babies of all ages when parents take time to return the facial expression and interact with them.

Early Smiles

Your new baby develops muscle movement during the first few weeks, including muscles in the face, and reflexive smiling is part of her muscle-testing process. Your child might smile while you observe her while she sleeps. Baby may be dreaming pleasant thoughts, but behavioral researchers claim your newborn uses her automatic reflexes to give muscles an early workout, and a smile is the result.

Reaction Smiles

The AAP calls baby-and-parent interaction to produce social smiles a dance that requires face time to teach. Babies learn by following your lead, and snuggling up close to your newborn and smiling shows him how to express happy feelings. Face time allows you and your child to bond. He'll learn to identify your face and smile when you change his diapers, feed him and give him hugs. The AAP says your child's smiles help you understand how he likes to be comforted, held and treated.

Emotions and Bonding

Take time to return your baby's smile, and she'll continue to show her pleasure by smiling to let you know she's happy. The AAP warns parents that failure to return smiles may result in your child turning to other methods to get your attention, including crying and fussing. Expand the smile fest with cooing and laughing, and your baby will likely follow your example when she's pleased. Your child may use other actions to communicate positive feelings, such as a squeal or arm and leg movements, as a signal to you that she's happy with her life, but baby also needs to know how to smile.

Grumpy Baby

A baby without the ability to return a smile is not normal. Pediatrician Mary Ellen Renna tells "Parents" magazine that parents should contact a pediatrician when baby hasn't shown a smile by the 12-week mark. The lack of smiling doesn't mean your baby is simply grumpy. The inability may signal some sort of developmental delay your doctor can identify. If you haven't modeled smiling for your baby, increase your face time. The AAP recommends modeling smiles for your baby while holding him and taking time to look into his eyes to communicate your love.