Did you ever wonder why your 7-year-old trips over his shoes, without picking them up? Or why your teenager doesn’t hear you when you ask him to make his bed? Or why your toddler spits out the carrots she loved just yesterday?
Despite the evidence of your own eyes and ears, there’s probably nothing wrong with your child’s senses. The sensory faculties of sight, hearing, taste, smell, and touch that allow us to perceive the environment are fine. It’s just that different stages of growth and development allow the child to use them in ways none of us would imagine – or at least not since we were kids ourselves.
Touch
The delicate, soft skin of an infant is loaded with sensory nerves, programmed to respond to touch. Think about how a baby just knows how to find the nipple when the side of his face is gently stroked, how many babies feel comforted when swaddled securely in a soft baby blanket, and how tiny babies respond to that inaugural bath, when for the first time they are wet and cooler than usual.
After all, a newborn has emerged from a warm, cozy environment, and at the end of pregnancy, conditions have grown crowded inside the uterus. This constant stimulation of the skin during pregnancy and labor makes swaddling a familiar and welcome feeling after delivery. This same sense of security is generated in the baby by holding her, or carrying her in a sling or carrier near the warmth of the parent’s body.
For a newborn, these encounters with touch aren’t just comforting, they can help him thrive. A report out of the Touch Research Institute from the University of Miami School of Medicine revealed that premature babies, who were much less cuddled and touched than their full-term counterparts, weren’t gaining weight at comparable rates. When infant massage and a program of therapeutic touch were introduced, these little ones gained more weight and improved their development.
Sight
Anyone who had poor vision as a young child can remember the first time he donned those prescription glasses. Who knew that tree bark had texture and that grass was actually a lot of individual blades?
Vision problems are commonly noticed when a child starts school, but there are a number of things that can be done to evaluate vision beforehand. Natario Couser, MD, is the medical director of Where Healthy Eyes and Ears Lead to Success (WHEELS), an initiative from Prevent Blindness Mid-Atlantic and MEDARVA Healthcare that conducts pre-school screening and educational programs to help identify children at risk. He says ophthalmologists, clinics, And programs like WHEELS are a valuable tool in diagnosing and treating problems before they can affect learning.
Another common issue with young children’s vision is strabismus (often called crossed eyes or lazy eye) when the child relies on the good eye and the weaker eye gets progressively weaker, potentially causing problems later in life. Because a young child is usually not able to verbalize visual problems, new technologies that allow even very young children to be tested in engaging and effective ways are crucial to eye health.
For children, the sense of sight is critical to learning success. “It is estimated that about eighty percent of the information children process during the school day is from visual stimuli,” says Dr. Couser, a pediatric ophthalmologist with Virginia Pediatric Ophthalmology Specialists. “If a child has problems seeing clearly, learning can be affected. Up to one in four children have visual impairments significant enough to affect learning. Fortunately, most of these problems can be easily treated with noninvasive techniques and eyeglasses.”
Taste
It’s amazing how your toddler will love squash one day and spit it out the next. And how about your tween? She wants to eat as healthily as possible, yet for her, pizza and pop-tarts are the two major food groups.
The sense of taste is more complex than you would think. It’s closely aligned with the sense of smell, says otolaryngologist Evan Reiter, MD, with VCU Health System’s department of otolaryngology. The taste buds, specialized nerve endings on the tongue, can distinguish several kinds of flavors, notably sweet, salty, bitter, and sour.
In addition, odors from foods we chew and eat naturally pass upward from the back of the mouth and throat to the nose, where they trigger our sense of smell. It is estimated that about two-thirds of what we perceive as food flavor is from our sense of smell, rather than our sense of taste. People who have lost their sense of smell can no longer taste, as anyone who has had a head cold with a badly stuffed up nose can tell you!
All taste buds are not alike. There is research indicating that tweens may be more sensitive to sweet flavors than younger or older children. Also, the overall sensitivity of the taste buds seems to increase and refine by the teenage years.
Children learn to identify what will taste good by automatically combining input from not only taste and smell, but also from sight. Foods that are more colorful and pleasing to the eye may be perceived as better tasting. Experience plays a role as well. If your child feels ill or throws up after eating something that may have tasted good at the time, he may have an aversion to that food in the future.
An unexpected link between taste preference and society was described in a Stanford University study. When kids were given unidentified foods, they preferred the flavors of a highly advertised food chain to similar foods from other sources. Food preference is an important area of scientific study, especially with the new emphasis on combating childhood obesity.
Smell
It is estimated that humans have about five million smell receptors, and that the peak sensitivity is at around eight years of age. It will gradually drop off with age, with women generally maintaining the sense of smell better than men. Believe it or not, your little dog has up to twenty times as many receptors as a human, explaining why his cousins are so effective in finding people and sniffing out drugs or explosives.
Tiny odor molecules carry smells in the air. When they enter the nose and land on these sensitive receptors, the information is quickly moved the short distance up to the brain, where specialized cells identify the information. This information is sent to several areas of the brain where we learn to identify the smells, we use the smells to help taste our food, and we form emotional links and memories from the smells.
“We’ve all had the experience of recalling an event when a particular odor wafts by,” says Richard Costanzo, PhD, professor of physiology and biophysics at VCU’s School of Medicine and a pioneer in the study of smell and taste disorders. “It may be a special perfume, chocolate chip cookies in the oven, or the smell of a gas leak. These are powerful emotional triggers That generate feelings and, in the case of a warning odor, prompt action. In that way, the sense of smell can truly be a life-saver.”
Hearing
Are you deaf? Am I talking to myself? These are common questions exasperated parents ask teenagers, says Travis Shaw, MD, ear, nose, throat, and sinus specialist. “Rest assured – this selective hearing loss is not a permanent condition and will go away without treatment, if not without a lot of parental frustration!”
Your ear is a sensitive instrument that collects and transmits sounds from the environment to the brain. Sound vibrations funnel through the canal, move the eardrum, which in turn moves the tiny bony ossicles in the middle ear, which are then converted into nerve impulses sent to the hearing centers of the brain.
This system starts to work while a baby is still inside the womb. She will hear and respond to noises and music in utero, and will quickly learn to recognize a parent’s voice soon after birth. She will have a developed sense of hearing soon after delivery, quite a bit sooner than the developing sense of sight.
Like the other senses, the sense of hearing has a great impact on learning and development. We learn to associate sounds with emotions. Soft music is relaxing; loud sounds may be distressing. Very loud sounds can sometimes be painful – and may actually damage the fragile receptor cells in the ear.
Hearing loss in a young child (but not necessarily with new and intermittent onset in a teenager!) Can be noted by simply observing a child’s reactions to sound. Good hearing is critical for language development, since we mimic sounds we hear, eventually evolving these into speech.
It is clear that the senses are truly our window on the world. Throughout our children’s lives, the information gathered using these faculties will help them mature into balanced and productive members of society. Science and medicine have developed insights, technology, and procedures that help us keep these windows wide open from the very beginning.