Your baby is learning to roll over, starting to sit up, and grabbing toys and other interesting objects.

While most of their energy now is spent developing motor skills, babies this age also are honing all five senses, understanding and anticipating more and more of what they see, hear, and feel.

Sight

As your baby's interaction with the environment increases, you should notice a corresponding rise in visual awareness. Your baby sees much more than just a few months ago, focuses without going cross-eyed, and distinguishes more colors.

Babies this age now can track even rapid motion with their eyes. Your baby can follow the course of a rolling ball and probably can focus on watching the quick movements of an older sibling playing nearby.

You may see your baby staring in concentration while holding a toy or studying his or her own hands.Hand-eye coordination is improving, so watch as your little one stares for a while at an object, then slowly reaches out to get it. The things babies see can now be explored in new tactile ways.

If your baby has been looking at the same toys or crib mobile for several months, now is a good time to change the scenery. Don't forget that around 5 or 6 months your baby will start to pull themselves up to a sitting position, so if you have a mobile over the crib or wall hangings within reach, remove them so your baby doesn't get hurt.

If your baby has been looking at the same toys or crib mobile for several months, now is a good time to change the scenery. Don't forget that babies older than 6 months will start to pull themselves up to a sitting position, so if you have a low-hanging mobile over the crib or wall hangings within reach, remove them so your baby doesn't get hurt.

Babies this age enjoy more complex designs and can distinguish colors. Try reading books with large, brightly colored pictures to your baby, who will enjoy staring at the pages. Stimulate your baby's vision with trips out into the world. Walks in the neighborhood, a trip to the supermarket, or an outing to the local zoo all provide wonderful opportunities for your baby to see new things.

Hearing

Hearing is crucial to developing the ability to talk, and your baby is learning the fundamentals of communication. When younger, your baby understood your meaning through the tone of your voice: soothing tones made your infant stop crying, agitated tones meant something was wrong.

Now, your little one is beginning to pick out the components of speech. Your baby can hear and pick up on the different sounds you make and the way words form sentences. By the end of this period, babies are responding to "no" and recognizing and responding to their own name. They also are starting to babble and make more attempts to imitate sounds. Make no mistake, these are your baby's early attempts at speaking and should be encouraged as much as possible.

Repeat sounds you hear your baby making and introduce simple words that apply to everyday life. Have "conversations" with your baby and wait for a pause in the babble to "answer." The give-and-take of these early discussions sets the stage for your baby's first real words in the months to come.

Taste and Smell

Your doctor may suggest the addition of solid foods to your baby's diet during this period. If so, introduce one new item at a time and wait several days before trying something else new. This will help you pinpoint any food allergies that may occur, and also discover which tastes your baby likes best.

While babies innately prefer sweet tastes, you'll want your baby to be exposed to a variety of foods. It may take several tries before your child starts to enjoy a new food so don't give up after the first or second attempt if he or she doesn't seem to like it.

Touch

The opportunities for exercising your baby's sense of touch at this age are endless, even during the course of a regular day. Let your baby roll a while in the coarse grass of your yard. See if your baby prefers to touch the silky trim of the baby blanket, or feel the texture of a carpet. Labeling the textures — "This is rough," "This is soft" — will help your baby learn more about the world.

Don't forget how important the feel of a gentle caress or a tender kiss is, and hold your baby when you are able. This kind of touching shows your baby that he or she is safe, secure, and loved.

Should I Be Concerned?

Between 4 and 7 months, you should see a noticeable increase in your baby's awareness of sights and sounds. Your baby should be responding appropriately to more and more visual and audio stimuli.

Talk to your doctor if your baby doesn't seem to:

• recognize you by sight
• be interested in looking at any new books, toys, or pictures
• have good control of eye motion or one or both eyes turn in or out consistently (although some crossing is still normal until 6 months)

Also speak to your doctor if you notice persistent tearing or extreme sensitivity to light. An evaluation also may be necessary if you have a family history of serious eye diseases or vision problems.

Since hearing is such a crucial component of language development, you'll also want to discuss with your doctor any concerns you have about your baby's hearing. If your baby doesn't seem to imitate simple sounds by 6 or 7 months, or shows no interest in babbling or having a "conversation" with you, ask your doctor about getting a hearing evaluation.

Warning signs of hearing problems to look for:

• no response to sound (for example, doesn't turn in direction of loud noise)
• response to only some sounds, not all (some children can hear certain pitches, some hear in only one ear)
• does not laugh out loud by 6 months
• does not babble or make a variety of sounds by 8 months, or concentrates only on making vibrating sounds that are felt in the throat rather than imitating sounds he or she can hear

Caught early, many vision and hearing problems can be treated successfully, so be sure to report any concerns you have to your doctor immediately.

Reviewed by: Mary L. Gavin, MD
Date reviewed: September 2011