The motor development was consisted of seven periods across the lifespan, each period is characterized by the different motor skills. Progression from one period to another would depend on the changes in three critical constraints, as well as individual’s skills and experiences. According to the developmental perspective, the changes in the motor skills were defined as sequential, cumulative and individual. Everyone would follow the same sequence of the motor development, however, age does not determine the sequence because the skills are built based on individual’s background experiences and knowledge.
The first stage of motor development is the prenatal period, it is the period from conception to birth. The prenatal period is characterized by three major sub periods: Germinal, embryonic and period. The germinal period represents the first two weeks after the fertilization, where the ovum attached the uterine wall and the cell layers are formed. The embryonic period began from two to eight weeks, when the cephalacadual and proximodistal growth took place. At this time, infants could move around to obtain the upright posture, where different parts of the body are also distinguishable. Our motor development began prenatally, usually started from the embryonic and fetal period. The fetal period started from two to nine months, when most of the body systems were getting more structurally developed. However, the organs and body systems were still functionally immature. The fetal period was characterized by rapid growth and organ completion, as well as reflex activities and movements. As early as three months, babies could demonstrate both spontaneous and reflexive movements. My mother told me that she first felt my kicking and hand movement around the fourth month, and she also went to do the ultrasound to check if I was a healthy baby. My mother kept the testing record updated, the doctor also told her about my gender when I was a six-month-old baby.
During the prenatal period, the development represented the interaction of heredity and environment. The organism constraints such as genetic makeup, would dominate the development, while the environmental constraints could also affect the development. Teratogen was an environmental factor that cause harm to the embryo or fetus, it could lead to the birth defects. However, the baby’s genetic makeup and the amount of exposure would play important roles that affect the degree of harmfulness. The epigenetic crisis represented a time of particular susceptibility to harm, that different trimester exposed to teratogen would lead to different degrees of functional or structural damages. I was a healthy baby and received high APGAR scores mainly because my mother did not drink alcohol nor smoke during the pregnancy. My mother was a housewife, she stayed home most of the time looking at baby pictures and listening to classical music. Her daily exercise was walking, when she had to go to the supermarket near my house. During the pregnancy, my mother’s life was simple and worriless, she was also a happy and a healthy mother.
The reflexive period started from birth to two weeks, the reflexive or spontaneous movements are used to insure the infant’s survival. There were two types of reflexes, the primitive and postural reflexes. The primitive reflexes were used for the protection and nutrition purposes, usually disappear by the sixth month. I demonstrated the rooting reflex when I was one month old, when my mother tactile my cheek, I immediately turned my head toward her finger (see picture five). My mom also told me that I used to like sucking my thumb before I go to sleep (see picture four). It showed sucking reflex, which was the biological response for the basic needs and helped infants to survive. The asymmetric tonic neck reflex appeared around the same time, when my right arm was extended and the left to keep my body facing a direction (see picture four). On the other hand, the postural reflexes are used for the development of later voluntary movements. The postural reflexes may never disappear, those reflexes also automatically provided the maintenance of infant’s upright position in relation to the environment. Setting up an upright posture could also help infants survive in the environment, as the environmental constraints began to have more influences on the development. Overall, the organism constraint dominated the development during the reflexive period, and the environmental constraints were influential.
The motor development of preadapted period would usually take place when an infant is around two weeks to a year old. During this early developmental period, the organism constraints played a dominated role, the environmental constraints were influential, and the task constraints organized the action. The goal of the movement would be the attainment of independent walking and independent finger feeding.
When I was an infant, I followed the sequence of motor development to obtain my upright posture. At two weeks, I couldn’t lift my head off the support surface to gaze about the environment. I would need help on lifting my head, therefore my mother would put her hand behind my trunk to support my body (see picture two). The posture at this age was the prone position (see picture one). At birth, infants would show their first motor movement by learning to prone. Soon after that, I began to elevate myself on my arms. As soon as I reached five months old, I was able to sit alone without support (see picture seven). Around five and half month old, I could demonstrate rolling, which was the earliest pattern of infant locomotion development. However, I skipped the stage of crawling, an important stage of motor development that helps infants to prepare for later walking skills. Because I was the oldest child in the family, my parents thought maybe I was too fat to demonstrate crawling (see picture six – I couldn’t crawl up to a chair). I thought the main reason for not crawling was that I often played with older children in our community.
Since I am able to see many “role models”, it is likely that I learn how to stand first, thus skipped the crawling. The environmental constraints played an important role for me in the process of learning to stand, walk, and later running. The rate enhancer would be the opportunity for me to play with the older children, and to learn more motor skills from them. However, the rate limiter and organism constraints for not acquiring the walking or running skills would be the strength. Because my mother was a housewife, she spent a lot of time taking care of me. She taught me how to stand by holding both of my arms first, to give me strength support (see picture nine). Soon I was able to acquire the standing motor skill, I can stand by myself (see picture ten). My parents then bought me a “walker” to help me learn how to walk (see picture eight). The walker was very helpful because it had wheels under the chair, I can actually go anywhere I wanted, just like a walking person.
Around approximately ten-months old, I began to cruise and showed walking patterns. However, the rate-limiter and constraint of walking is my posture, because I have not yet obtained the upright posture for walking. It might be the fact that I wanted to play with the older children, and I was also able to see how other children walk, I showed early mature walking patterns at the age of eleven-months old. At this time, I was an independent walker with newly learned walking skills! When I first began to walk, I was walking very slowly, making short strides and put my arms up high to make balance. The primary rate limiters for not acquiring the upright position in walking were the postural control and strength. My body proportion was also a disadvantage to obtain the walking skills, because the proportion of my head was thirty percent of the body while my legs are only fifteen percent. I had heavy body and short legs, (heavy center of mass and light base of support) it would be hard for me to keep the upright postural control and balance for walking pattern.
At this point, the environmental and task constraints would show more influences on the motor development. As I obtained the skill of independent bipedal locomotion (walking), I encountered movement problems. According to dynamical systems perspective, the degrees of freedom and context-conditioned variability are the problems for a new walker. If I was able to go anywhere I want, then I had the right of choosing where to go, or how to get to the desired place. However, the problems were solved from self-organization of the body system and the emerging of the constraints. The major rate limiters for not acquiring the running skills would mainly come from the organism constraints, such as the posture, strength and motivation. For me, I was motivated to learn those motor skills because I wanted to play with older children. I was a fast learner also because my parents spent time and efforts to help me obtain the locomotion skills. Therefore, six months after I learned how to walk, I was able to run anywhere I want to go (see picture eleven). I have also developed manipulative skills as I learned to use hands to feed myself, and I was able to show better hand-eye coordination and movement.
Fundamental Motor Skills Period
The fundamental skills period began at the age of one, ends by the age of seven. In a way, this period of time would be a sensitive period to learn certain motor skills for later skillful movements. The fundamental motor skills period would be the building blocks for later emerging skills, and acquiring those skills were essential to later developing motor skills. Those skills were characterized as the phylogenetic skills, which are skills typical to individuals. Obtaining the locomotion and manipulative skills would be the fundamental and developmental process to obtain later movements. At this time, both fine and gross mother skills were beginning to develop. Those skills might not be maturational determined, and the arm and leg coordination were still immature. When I was a year old, I would throw a ball only using my arm movement, my legs and trunks barely made any movements. As I grow two more years older, I could demonstrate the pattern of block rotation, at the point where my body moved as one long axis.
I would step my feet first, then put my arm backward ready to throw. My arm, leg and trunk have lined up as straight along the axis, and allowed me to have more power in throwing. Around the age of six or seven, I was able to demonstrate the differentiated rotation movement. My arms, legs, hip and shoulder would move separately as I began to obtain higher level of throwing. When I threw, my hip usually showed the first movement, followed by my shoulder and arms. At this young age, I had difficulties to demonstrate the locomotion skills of skipping. Skipping would be the latest motor movement for children to learn, not only because it had higher level of difficulty, but also it required the ability to hop on each leg sequentially. Older children would have no problem demonstrate skipping because they have better postural control, movements and coordination.
Fine motor skills were begun to develop, such as drawing skills. When I was a one-year-old child, I would draw some scribbles on the paper, the outline and the shape of the objects were not clear to see. As I grew older, I showed more realistic drawings by making more clear lines, shapes and forms. I was also able to draw many different emotions on the faces and I used more variation in coloring my pictures.
At the age of six, both my sister and I were interested to learn roller-skating. My father had brought two roller-skates for us, and we also took roller-skating class. It was really hard for me when I first started to learn roller-skating, and it was difficult to keep the balance. Skating is a complex motor skill because the arm and leg movements could not be in the same direction. My arm and leg coordination was also messed up, because I would always freeze my arms as I put it up high to obtain the balance. After many practices and countless falls, my sister and I have finally learned some basic fundamental skills of roller-skating (see picture fourteen). We wore kneepads because it was impossible not to fall, but we took them off as we were able to perform better in roller-skating.
My father have also signed me up for a swim class, because he thought swimming was a very healthy exercise and it would help me to become healthier (see picture fifteen). Swimming was also a complex motor activity, while I tried to keep my legs padding in the water, the degrees of freedom limited me from doing any arm movements. Overall, the organism constraints dominated the development, the environmental constraints were influential and the task constraints organized the action. The rate limiter would be the proficiency barrier, the immature functional organism constraints held me back from acquiring the higher level of motor movement.
Context-Specific Skills Period
As I began to get older, around the age of seven to eleven, I reached the context specific period. The context specific period was characterized by the ontogenetic skills, which are skills unique to individual. Most children at this period have obtained context-specific knowledge and experience to acquire their individualized skills. The context-specific period also represented a transition period between the attainment of the fundamental motor skills and the transformation into skillful motor performance. Because it was influenced more by the environmental and task constrains, motivation and parental support would be important to help children move on successfully to the skillful period. Organism constraints also played important roles, such as physical, social and emotional development. At this time, I have grown taller and gained more body weight.
There were also changes in my cardiovascular system, the aerobic power increased because I was able to uptake more amount of oxygen at a time. The improvement can be seen from exercising, such as swimming. I was still at the swimming class, my swimming had improved and I was moved up to a higher level. In order to graduate from the swimming class, it was required for everyone to pass an examination by performing the swimming skills in a weekly competition. I remembered how nervous I was when I had to swim butterfly in the competition, I felt so relieved when I passed the examination and get the award. Because of the training from swim class, I had more swimming experiences and obtained better swimming skills. Swimming has also helped me to improve arm and leg coordination in the development of gross motor skills.
At this time, both fine and gross motor skills have also improved. I was still in love with roller-skating, but I have also fallen in love with ice-skating. Once my friends asked me to go ice-skating with them, they were surprised to see my skating skills. I have never gone ice-skating before, but because I knew how to roller-skate, thus it was easier for me to stay balanced. I showed better skating skills because I had already obtained the gross motor skills needed for skating, the arm and leg coordination had also improved as I gained more skating experiences. During the winter of my senior year in high school, my uncle asked me to go skiing with him. I was a little nervous because I have never skied before, and also I heard that skiing was a dangerous sport. However, all those worries had gone away as I began to learn skiing. As my uncle taught me how to ski, he was surprised to the pattern of well-coordinated arm and leg movement, as well as my balance.
I was still in love with flute, and I had also become a member of the concert band in my middle school. At this time, I am more skillful in playing flute. Because I have been practicing everyday, my fingers are also more flexible as I gained more experiences. As I practiced more, the perceptual and speed processing increased, which allowed me to read the music faster. During my last year of the school, our concert band was informed to attend a National Musical Competition. We were invited to go to Florida State for three days for the competition, which we had to play against ten middle schools in the United States (see picture sixteen).
I still could remember that moment when the judge announced our school to be the one winning the first price, for a moment I thought I was dreaming. It was unbelievable, it was the happiest moment in my life, and all the hard work has been paid off. I felt so proud to be a member of our concert band, because I had also contributed my effort to win the price. My parents and friends were very happy for me, and they encouraged me to take more challenges. The environmental and task constraints are the rate enhancers to help me move on to the next skillful period, and I have also gained more confidence in myself. However, the rate limiter for not acquiring the skillful skills would be the proficiency barrier, because of the functional organism limitation. I have not yet obtained the skillfulness of the perceptual cognitive functioning, such as not having enough knowledge base and a slower speed of processing.
The skillful period usually started at the age of eleven, the word “skillfulness” could also represent context-specific because the skills were also individualized. After winning the first price and gaining the recognition, I decided to devote myself into playing flute. My parents supported me, they have also asked a professional flutist to be my tutor. With the hope that I might be a professional flutist someday, I have been practicing two hours per day to improve my playing skills. It was the organism constraints that influenced my determination and persistency, because I was motivated go achieve the goal (see picture seventeen). The environmental constraint also played an important role during the skillful period. For me, not only because my parents set high expectations toward me, but also we were in the middle socio-economic status where the money for tutoring was affordable. If I ever become a successful swimmer or flute player, I’d thank my parents for giving me the opportunities.
I have also been consistently going to swim, and it had become my regular exercise every week. At this time, my father did not need to force me nor sign me up for a swim class, because I liked swimming as much as I loved playing flute. I would still go ice-skating with my friends, and I have also learned how to perform some tricks. My uncle would still take me up to the mountain every winter to ski, I was able to ski on a higher hills and under more complex tasks. For those motor activities, I know if I were able to be persistent to practice, it would enhance my knowledge and experiences and my performance would get closer to the professional level. From the dynamical systems perspective, self-organizing system and organism constraints have set a balanced, equilibrium and coordinated state in the individuals.
The compensation period represented a time when a skilled individual is compensating for a change in an organism constraint. Throughout the life span, our motor skills performance would keep on improving. As we reached at the point where organism constraints took place to change, our motor skills performance would decline. It showed the adjustment of our motor behavior, and our movements might not be as skillful. Due to the changes in organism constraints, a person at this period of time was also particularly vulnerable in gross motor skills, because those skills required larger forces and aerobic efforts. Changes in organism constraints are due to the declines in the body system such as maximum oxygen uptake, stroke volume, or maximum heart rate. There would be changes in our fundamental motor skills, such as locomotion and balance. At this time, our walking skills and balance have declined and we became more vulnerable to falls and injuries. It is also because the decreased bone mass, led to the changes in strength characteristics of the bones. In addition, our auditory and somatosensory systems would not be functioning well; a person could suffer from hearing loss or loss of sensitivity.
Changes in the environmental constraints would also influence an individual at this period of time. The lifestyle, societal expectations or socio-economic status would make differences on their perceptions and actions. At the compensation period, the declining of physical abilities had impact on individual’s psychological and emotional systems. A person at this period might lose the interests in doing their favorite sports, or change the interest or hobby. Other than obtaining an active lifestyle, the higher socio-economic status would play a role to help an individual at this period to live longer and healthier, because of the better medical care.
As for now and the future, I would keep up with the concert band in the University of Maryland College Park, and attend as many musical performance as I could. I would still take private lessons and practice one to two hours per day to get myself on the right track. I know my dream would come true if I could keep up my persistency and hard work. This could be characterized as my organism constraints, because I was self-motivated and have confidence at what I do. My uncle would still invite me to go skiing with him every winter, we have been great skiing partners. However, it was harder to keep up with the skiing skills at a certain level if you just practice once or twice a year. The environmental constraint had limited my skiing skills, if I were to live somewhere in Alaska, I would have better chance to be a skillful skier. I also would continue my swimming practices, because it would be hard to catch up the butterfly if I stopped practicing it. I know I would never forget how to master those motor skill performances, they have been a part of me. However, to reach a certain level of expectation and goals, I would still need my parental support and encouragement, as well as my persistency and practices.