Fine motor skill

Fine motor skill (or dexterity) is the coordination of small muscle movements—usually involving the synchronization of hands and fingers—with the eyes. The complex levels of manual dexterity that humans exhibit can be attributed to and demonstrated in tasks controlled by the nervous system. Fine motor skills aid in the growth of intelligence and develop continuously throughout the stages of human development.

Types of motor skills

Motor skills are movements and actions of the muscles. Typically, they are categorized into two groups: gross motor skills and fine motor skills. Gross motor skills are involved in movement and coordination of the arms, legs, and other large body parts and movements. They participate in actions such as running, crawling, swimming, etc. Fine motor skills are involved in smaller movements that occur in the wrists, hands, fingers, and the feet and toes. They participate in smaller actions such as picking up objects between the thumb and finger, writing carefully, and even blinking. These two motor skills work together to provide coordination.

Developmental stages

Through each developmental stage of a child’s life and throughout our lifetime motor skills gradually develop. They are first seen during a child’s development stages: infancy, toddlerhood, preschool and school age. "Basic” fine motor skills gradually develop and are typically mastered between the ages of 6-12 in children. These skills will keep developing with age, practice and the increased use of muscles while playing sports, playing an instrument, using the computer, and writing. If deemed necessary, occupational therapy can help improve overall fine motor skills.^[1]

Infancy

The first motor skills, beginning from birth, are initially characterized by involuntary reflexes.^[2] The most notable involuntary reflex is the Darwinian Reflex, a primitive reflex displayed in new-born babies. These involuntary muscle movements are temporary and often disappear after the first two months. After eight weeks, the infant will begin to voluntarily use their fingers to touch. However, their ability to grab objects is still undeveloped at this point.

Infant displaying the palmar grasp.

At two or five months the infant will begin to develop hand-eye coordination, and they will start reaching for and grasping objects. In this way, they improve their overall grasping skills. A child will start randomly grabbing tangible and intangible objects indiscriminately.^[3] Infant six months of age and older should be able to pick up toys with one hand and look at the object prior to reaching out to grab the object, thereby examining dimensionality of objects before grabbing it.^[4] The next developmental milestone is between seven to twelve months, when a series of fine motor skills begins to develop. These include, but are not limited to, increase in grip, enhancement of vision, pointing with the index finger, smoothly transferring objects from one hand to the other, as well as using the pincer grip (with the thumb and index fingers) to pick up tiny objects with precision.^[5]

Toddlerhood

Writing abilities are a major fine motor skill.

By the time a child is one year old, their fine motor skills have developed to allow the manipulation of objects with greater intent.

As children manipulate objects with purpose, they gain experience identifying objects based on their shape, size, and weight. By engaging in hands-on play the child learns that some objects are heavy, requiring more force to move them; that some are small, easily slipping through the fingers; and that other objects come apart and can possibly be put back together again. This type of play is essential for the development of not only the child's fine motor skills, but also for learning how the world works.^[6]

It is during this stage in the development of fine motor skills that a toddler will show dominance of the preferred hand, be it either right or left.

Preschool

Children typically attend preschool between the ages of 2 and 5. At this time, the child is capable of grasping objects using the static tripod grasp, which is the combined use of the index, thumb, and middle finger. A preschooler's motor skills are moderate, allowing the child to cut shapes out of paper, draw or trace over vertical lines with crayons, button their clothes, and pick up objects. A preferred hand dominates the majority of their activities. They also develop sensory awareness and interpret their environment by using their senses and coordinate movements based on that.^[7]

The National Center of Teaching and Learning illustrates the abilities that preschoolers should have improved through their fine motor skills in several domains. Children use their motor skills by sorting and manipulating geometric shapes, making patterns, and using measurement tools to build their math skills. By using writing tools and reading books, they build their language and literacy. Arts and crafts activities like cutting and gluing paper, finger painting, and dressing up develops their creativity. Parents can support this development by intervening when the child does not perform the fine motor activity correctly, making use of several senses in a learning activity, and offer activities that the child will be successful with.^[7]

Developmental disabilities may render a child incapable of performing certain motor activities, such as drawing or building blocks.^[8] Fine motor skills acquired during this stage aids in the later advancement and understanding of subjects such as science and reading.^[9] A study by the American Journal of Occupational Therapy, which included twenty-six preschoolers who had received occupational therapy on a weekly basis, showed overall advancements in the preschoolers' fine motor skill area. The results showed a link between in-hand manipulation, eye-hand coordination, and grasping strength with the child's motor skills, self-care and social function. In addition, these children were shown to have better mobility and self-sustainment.^[1]

School age

During the ages between 5 and 7 the fine motor skills will have developed to a much higher degree, and are now being refined. As the child interacts with objects the movements of the elbows and shoulders should be less apparent, as should the movements of wrist and fingers.

Children should be able to make precise cuts with scissors. For example, cutting out squares and holding them in a more common and mature manner. The child's movements should become fluid as the arms and hands become more in sync with each other. The child should also be able to write more precisely on lines, and print letters and numbers with greater clarity.^[10]

Common problems

Fine motor skills can become impaired. Some reasons for impairment could be injury, illness, stroke, congenital deformities, cerebral palsy, and developmental disabilities. Problems with the brain, spinal cord, peripheral nerves, muscles, or joints can also have an effect on fine motor skills, and decrease control. If an infant or child up to age five is not developing their fine motor skills, they will show signs of difficulty controlling coordinated body movements with the hands, fingers, and face. In young children, the delay in the ability to sit up or learn to walk can be an early sign that there will be issues with fine motor skills. Children may also show signs of difficulty with tasks such as cutting with scissors, drawing lines, folding clothes, holding a pencil and writing, and zipping a zipper. These are tasks that involve fine motor skills, and if a child has difficulty with these they might have poor hand eye coordination and could need therapy to improve their skills.

Assessment

Fine motor skills can be assess with standardized and non-standardized tests in children and adults. Fine-motor assessments can include force matching tasks. Humans exhibit a high degree of accuracy in force matching tasks where an individual is instructed to match a reference force applied to a finger with the same or different finger.^[11] Humans also exhibit a high degree of accuracy during grip force matching tasks.^[12] These aspects of manual dexterity are apparent in the ability of humans to effectively use tools. Other assessments include but are not limited to PDMS "The Peabody Developmental Scales".^[13] PDMS is an evaluation done for children from birth till the age seven that examines the child's ability to grasp a variety of objects, the development of eye-hand coordination, and the child's overall finger dexterity.^[13] Similar to PDMS, Visual-motor integration assessment,VMI-R, is an assessment that examines the visual motor integration system which demonstrates and points out possible learning disabilities that are often related to delays in visual perception and fine-motor skills such as poor hand-eye coordination.^[14] Because additionally advancements in mathematics and language skills are directly corollated to the development of the fine motor system, it is essential that children acquire the fine motor skills that are needed to interact with the environment at an early stage.^[15]

References

External links

• Fine Motor Control - MedlinePlus (2011)
• Handwriting and Fine Motor Skills: New Insights into Autism - Psychology Today. (2009)
• Watch How You Hold That Crayon - The New York Times (2010)
• Fine Motor Skills (October 2014)