Motor Development in Infancy

Infancy refers to the development period from birth to two years.

A motor means movements of the bodies muscles to perform a certain task. Reflexes are the most basic. Reflexes have survival value.

For example, The rooting reflex (Head turns toward source of stimulation) helps a breastfed baby find the mother’s nipple. It is only seen when baby is hungry and touched by another person, not when they touch themselves (Rochat & Hespos, 1997).

Reflex 

A reflex is an inborn, automatic, organized, involuntary and most obvious response to a particular form of stimulation by Neonates.

• Sucking reflex
• The eye-blink reflex -remains functional throughout the full life span.
• swimming reflex- Baby paddles and kicks in swimming motion in pool of water. It disappear after a few months.
• Gag reflex- to clear its throat.
• The Babinski reflex-  occurs after the sole of the foot has been firmly stroked.
• Stepping reflex
• Grasping reflex
• Startle reflex
• Moro reflex- “embracing” motion by arching back, extending legs, throwing arms outward, and then bringing arms in toward the body. Similar to primates’ protection from falling.

There are broadly two types of Motor skills

1. Gross Motor skills
2. Fine Motor Skills

1. Gross Motor Skills–

These are major muscles activities which help child to move around, like sitting upright and walking,

Head holding –They wiggle their arms and legs and may try to lift their heavy heads when placed on their stomachs.

Crawling appears typically between 8 and 10 months. Initial efforts are the forerunners of crawling, in which babies coordinate the motions of their arms and legs and propel themselves forward.

Walking around the age of 9 months, most infants are able to walk by supporting themselves on furniture, and half of all infants can walk well by the end of their first year of life.

Learning to move around, they are perfecting the ability to remain in a stationary sitting position. Seated upright without support.

2. Fine Motor Skills- 

These are fine muscle movements involving fine muscles. Smaller movements.

Newborns also make poorly coordinated swipes, called prereaching, toward an object in front of them, but because of poor arm and hand control they rarely contact the object.

By the time they are two years old, children can carefully hold a cup, bring it to their lips, and take a drink without spilling a drop.

Simple skills are combined into more sophisticated ones like Grasping, reaching. holding objects using fingers.

The newborn’s grasp reflex is replaced by the ulnar grasp, a clumsy motion in which the baby’s fingers close against the palm.

For example, infants first begin picking things up with their whole hand. As they get older, they use a pincer grasp, where thumb and index finger meet to form a circle. The pincer grasp allows for considerably more precise motor control (Barrett & Needham, 2008; Thoermer et al., 2013; Dionisio et al., 2015).

Dynamic Systems Theory

Developmentalist Esther Thelen. To explain how motor skills develop and are coordinated. How motor behaviors are assembled?

According to Esther Thelen , “assembled,” means the coordination of a variety of skills that develop in a child, ranging from the development of an infant’s muscles, its perceptual abilities & nervous system, as well as its motivation to carry out particular motor activities, and support from the environment (Thelen & Bates, 2003; Thelen & Smith, 2006).

According to dynamic systems theory, beginning to crawl, is not just dependent on the brain initiating a “crawling program” but it requires the coordination of muscles, perception, cognition, and motivation.

Dynamic systems theory emphasizes how children’s exploratory activities, lead them to advancements in motor skills (Corbetta & Snapp-Childs, 2009).

Theory emphasis on a child’s own motivation (a cognitive state) in advancing important aspects of motor development. e.g. infants need to be motivated to touch something out of their reach in order to develop the skills they need to crawl to it.

Milestones of Motor Development

Frankenburg and colleagues (1992) gave following milestone on motor development.

• 3.2 months: rolling over
• 3.3 months: grasping rattle
• 5.9 months: sitting without support
• 7.2 months: standing while holding on
• 8.2 months: grasping with thumb and finger
• 11.5 months: standing alone well
• 12.3 months: walking well
• 16.6 months: walking up steps
• 23.8 months: jumping in place

Test for Motor Skill Development in Infancy

Norm- the average performance of a large sample of children of a given age. There are few important test which can be used to asses children development and whether they have attended required milestone or not.

1. Brazelton Neonatal Behavioral Assessment Scale (NBAS), – To determine infants’ neurological and behavioral responses to their environment.

The NBAS provides a supplement to the traditional Apgar test that is given immediately following birth. Taking about 30 minutes to administer, the NBAS includes 27 separate categories of responses that constitute four general aspects of infants’ behavior:

1. Interactions with others (such as alertness and cuddliness),
2. Motor behavior,
3. Physiological control (such as the ability to be soothed after being upset), and
4. Responses to stress (Brazelton, 1990; Canals, Fernandez-Ballart, & Espuro, 2003; Ohta & Ohgi, 2013).

References

Feldman, R. S., & Babu, N. (2011). Discovering the Life Span. Indian subcontinent adaptation, New Delhi: Dorling Kindersley India pvt ltd.

Berk, L. E. (2004). Development through the lifespan. (3rd Ed). New Delhi: Pearson Education Dorling Kindersley India pvt ltd.