Typical and Atypical Motor Development

Parents and health practitioners often track and measure a child’s developmental milestones from infancy to middle school. Developmental milestones include physical or behavioral signs of physical, social, and cognitive progress that lead to mastery over one’s environment. Smiling, crawling, manipulating objects, walking, self-care, and talking are examples of developmental milestones that provide valuable insight into a child’s development.

Most children develop skills in similar patterns and at similar times. But attaining milestones varies, based on each child’s family and personal history and environment. Therefore, milestones are generally reported in age ranges, rather than by a specific age.

Atypical Motor Development

Every child is unique. Each develops at his or her own pace and style. You might be concerned if your child is not yet crawling or walking when many peers are already displaying this skill. But remember that there are variations in typical development. That’s why developmental milestones are noted as ranges.

Is your infant or child showing significant delays or different patterns of achieving major milestones? This could be a sign of a motor or movement disorder. These are examples: a child who cannot maintain sitting by the tenth month or a child whose legs get very stiff every time he tries to roll over. Older children may also be displaying atypical development if they are not able to eat with utensils or dress or undress, or if they have trouble cutting with scissors or drawing.

Parents and family members who have concerns about a child’s development should bring their concerns to their health care providers as soon as possible. Sometimes all parents need is information about typical developmental. However, if you continue to see problems with your child’s development, you may need to be assertive to obtain the appropriate referrals to specialists.

Pediatricians may refer a child for further evaluation and testing with a neurologist , orthopedist ( or other specialist. The doctor may want to use specialized tests, such as X-rays, magnetic resonance imaging (MRI) , an electroencephalogram (EEG) , or laboratory tests to gather information about your child’s brain, spine, or musculoskeletal system.

The causes of motor delays are many. They include these factors:

  • Genetics
  • Intrauterine and other environmental factors
  • Prematurity

In some cases, the cause is unknown. Children with persistent, serious motor skill delays may eventually receive a specific diagnosis such as one of these:

  • Cerebral palsy
  • Muscular dystrophy
  • Spina bifida
  • Congenital hypotonia
  • Progressive metabolic disorder


Miller, L. J. and Fuller, D. A (2007) Sensational kids: Hope And Help for Children With Sensory Processing Disorder. New York: Penguin Group.

Tecklin, J. S. (2007) Pediatric Physical Therapy. Philadelphia, PA: Lippincott Williams & Wilkins.


Wilms Floet, A.M. (2006) “Motor Skills Disorder.” Emedicine: Medscape’s Continually Updated Clinical Reference.

How the Eye and the Brain Work Together


(Blind Babies Foundation)

  1. Light rays enter the eyes by passing through the cornea, the aqueous, the pupil, the lens, the vitreous, and then striking the light sensitive nerve cells (rods and cones) in the retina.
  2. Visual processing begins in the retina. Light energy produces chemical changes in the retina’s light sensitive cells. These cells, in turn, produce electrical activity.
  3. Nerve fibers from these cells join at the back of the eye to form the optic nerve.
  4. The optic nerve of each eye meets the other at the optic chiasm. Medial nerves of each optic nerve cross, but lateral nerves stay on the same side. The overlap of nerve fibers allows for depth perception.
  5. Electrical impulses are communicated to the visual cortex of the brain by way of the optic nerve.
  6. The visual cortex makes sense of the electrical impulses, and either files the information for future reference or sends a message to a motor area for action.

Nearsightedness (Myopia), and Farsightedness (Hyperopia)

Near and farsightedness are the result of varying- shaped eyeballs that cause light to focus in front of or behind the retina.

Perfect Vision


Light is focused from near and far objects exactly on the retina.


Light from near objects focuses behind the retina. Light from far objects focuses in front of the retina.

Compilation by Blind Babies Foundation, 1998


Aqueous – a clear watery fluid that fills the space between the cornea and the vitreous. It is responsible for nourishing the cornea, iris, lens, and maintaining the intraocular pressure.

Canal of Schlemm – is responsible for moving the aqueous from the front chamber in the eye through aqueous veins into the bloodstream.

Ciliary Body – is made up of ciliary muscle which helps the accommodation of the lens and controls the intraocular pressure of the eye. It is also where the aqueous is made.

Cones – light sensitive receptor cells mostly found in the central part of the retina. It is responsible for sharp visual acuity and the discrimination of color.

Conjunctiva – a transparent mucous membrane that covers the outer surface of the eyeball except for the cornea. It also lines the inner surface of the eyelid.

Cornea – the clear cone over the front part of the eye. It is responsible for most of the optical power of the eye.

Choroid – a layer of the eye found between the retina and the sclera. It contains major blood vessels and provides nourishment to the outer layers of the retina.

Fovea – is located in the center of the macula. It provides the sharpest vision.

Iris – a colored circular muscle that gives us the color of our eyes. It is responsible for controlling the amount of light that gets into the eye.

Lens – is responsible for bringing rays of light into focus on the retina. It is a clear oval structure suspended behind the iris which can contract and expand as needed to provide additional focusing power.

Macula – a small central area of the retina responsible for fine central visual acuity.

Optic Nerve – carries the light impulses for sight from the retina to the brain.

Retina – the most active area of the eye where the rods and cones are found. These receptors pick up the bits and pieces of the visual signals and transport them to the optic nerve for transmission to the brain.

Rods – light sensitive receptor cells mostly found in the peripheral part of the retina. They are responsible for night vision.

Sclera – the protective outer layer of the eye.

Vitreous – a clear jello- like substance between the lens and the retina that provides the structural support to the eye.



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Toolkit: Sensory Awareness in Your Classroom

Many teachers are aware of the need to recognize what a child’s sensory system is telling him. This can help the child with cooperation and improve attention and behavior in the classroom. Here are some ideas on how to organize the classroom environment to decrease sensory over-stimulation. Here are also some classroom activities that provide a sensory-rich experience for young students.

Classroom Environment:

  • Decrease visual over-stimulation by limiting the number of hangings on the walls and ceiling
  • Avoid classroom clutter by providing containers for toys labeled with a picture of items found inside
  • Decrease auditory over-stimulation by dividing a large classroom into smaller play areas. Place children in small groups for these activities for some part of the day.
  • Provide a quiet space that children can retreat to when over-stimulated. Define this space by setting up a tent or drapes to make it darker and provide a rocking chair or pillows or bean bags to lie on.

Classroom Activities:

  • For children who are sensory seekers, allow ample time for outdoor and indoor gross motor play. Emphasize climbing, hanging from monkey bars, pushing/pulling heavy items, jumping on trampolines or jump ropes, rolling, and swinging.
  • For children who have trouble sitting still or concentrating, provide access to small fidget toys. Or allow students to sit on a large exercise ball, wiggle cushion, or bean bag, when appropriate.
  • When appropriate and with supervision, encourage chewing on crunchy or chewy items (licorice sticks, pretzels, carrots, chewing gum).
  • Incorporate texture into fine motor/art projects: add sand or oatmeal to finger paints, use scented Play-Doh or wet clay, and have areas for water play.
  • When working on writing, encourage students to try writing with color-change markers, scented markers, Magna Doodle™, battery-operated pens, sidewalk chalk, finger paint, pudding, or shaving cream.


How Your Child’s Sensory System Develops

What is sensory development? In general, it refers to the maturing of the five familiar senses: hearing, smell, taste, touch, and vision. It also involves the way your baby or child’s nervous system receives input from these senses and then forms an appropriate motor or behavioral response. This is known as sensory processing or sensory integration.

Besides organizing the input from the five basic senses, sensory processing also focuses on the sensation of movement. Your baby explores and discovers the world through her senses. Babies are born with most of these senses nearly fully developed. But some subtle changes occur through the end of a child’s second year.

A problem with just one sensory system can greatly affect your child’s overall health and development. For example, when a baby’s hearing is not optimal and remains uncorrected, her speech and language development, communication, and learning may be delayed. You will want to understand how your child’s sensory systems develop. And be aware of any signs of concern. This will help ensure your child reaches her full potential.

What changes can I expect in my baby’s sensory development?

It’s helpful to watch for these changes in your child’s sensory development.

  • Hearing: Newborns can’t hear certain very quiet sounds. But, for the most part, their sense of hearing is already well developed. After about three months, sh e will show you she hears a sound by turning her head toward the direction of the sound. By four to eight months, she will hear the full range of sound frequencies.
  • Smell: A newborn’s sense of smell is so acute that she can already tell the difference between the smell of her mother’s milk and that of another mother. Researchers conducted experiments where two breast pads (one from the infant’s mother, the other from another lactating mother) were placed at the sides of the newborns’ heads. The babies reliably turned towards the breast pad of their own mothers. By about age five, your child can identify some foods by smell.
  • Taste: A newborn can distinguish between sweet, salty, sour, and bitter tastes. She shows a preference for sweet taste, such as breast milk, and for salty tastes later on. Your baby will achieve a full sensitivity to taste by 12 to 19 months.
  • Touch: The term touch here is used to describe all of the physical sensations that can be felt through the skin. Touch is actually not a single sense, but several. There are separate nerves in the skin to register heat, cold, pressure, pain, and touch. At birth or shortly after, your baby can distinguish between hot and cold temperatures and feel pain. Your baby’s hands and mouth are especially sensitive to touch. Between one to nine months of age, she will be able to distinguish differences in textures with hands and mouth. As a preschooler, she will be able to distinguish size and shape differences by touch.
  • Vision: Newborns can focus on objects about eight to 15 inches away. By one month, she will see about three feet away. At birth, she has limited color vision. But by two months, she can discriminate between basic colors. She will achieve full color vision between four and seven months of age. Depth perception develops between three and seven months. It will achieve full adult acuity (20/25) during her second year.
  • Sensory Processing: Given all of the sensory information a newborn can take in, she must begin to develop her processing skills and learn how to use the incoming sensory information to effectively act on her environment. When overstimulated by all of this sensory information, an infant will need help to calm herself. As she matures, she will learn self-regulation and display the skills needed to calm herself. In tandem with developing better control of her motor skills, her system will be learning to process the sensation of movement coming from her body through the vestibular and proprioceptive nerve receptors. As she matures, she will then learn to use all of the sights, sounds, and other sensory information in the environment to explore and learn about herself and her world.

Sensory Friendly Films and Family Movies

A special experience for any child is a visit to a local movie theater to watch a film with their family. For a child with special needs or a sensory processing disorder, a visit to a local movie theater isn’t the typical fun experience and may be filled with anxiety and fear. A dark movie theater may be scary to a child with special needs. If they are diagnosed with a visual impairment, they may not see the screen. Children with Attention-Deficit/Hyperactivity Disorder (ADHD) or autism may be uncomfortable sitting in a movie chair for an extended period of time. Loud noises and bright images may also affect a child’s sensitivity to their surroundings. If it is a three dimensional or 3-D movie, an entirely different set of problems may occur including health risks and the potential for headaches or seizures.

Luckily, more movie theaters recognize the sensory needs of these children. AMC Theaters is a leader in providing sensory friendly films to families of children with special needs across the US. AMC Theater auditoriums, through a partnership with Autism Society, have their lights brought up and the sound turned down. Families are permitted to bring in their own diet restricted snacks. There are no previews or advertisements and children with disabilities or special needs are welcome to get up to walk around, dance and even sing. Although the program was initially created to address the needs of children on the Autism Spectrum Disorder (ASD), the sensory friendly steps AMC Theaters has taken, makes it a more enjoyable experience for any child with a sensory processing disorder or disability. To find a theater near you, visit AMC Theaters Sensory Friendly Film Showings or the Autism Society.