order to have a control of a particular task. One of the pioneer in the field of of child development and fathers on developmental milestones is Arnold Gesell (1880-1961). Gesell was one of the first professionals to put into practice a quantity study of human development from birth to adolescence. He started his work with pre-scholars and then he expanded his work with ages of five to ten and then ten to sixteen (Gesell, Arnold (1880-1961), 2010).
Gesell descovered how infants and children go through specific phases and develop certain motor skills. Based on his studies, he came up with a theory that all children go by certain maturational stages or developmental milestones basically the same way. Children advance through these stages as expected over time and independently of learning (Gesell, Arnold, 2008).
Gesell trained researchers on how to collect data and produce information which became a topic of interest between parents and educators. The results of his studies was used to create Gesell Development Schedules, which is used in toddlers until six years of age; giving emphasis to motor, language development, adaptive and personal social behaviors (Gesell, Arnold (1880-1961), 2010).
General trends in motor development
Toddlers and youngsters will learn before anything else to have control of their bodies in order to be able to execute daily living activities. The fulfillment of basic needs like eating, drinking, urinating, and defecating as well as avoidance of dangerous situations can be done with minimum effort while motor control skills are developed. The ability to move head, eyes, operating or grabbing objects, sitting, crawling, walking, jumping are actions fundamental to social and intellectual growth (Ragsdale, 1941).
The creation of language sounds is considered the first of all motor process; following handwriting that must be controlled as motor behavior previous to become a vital and useful tool (Ragsdale, 1941). All characteristics of motor development will show an ongoing increase with age throughout maturity; including movement, the complexity of movements, stability of motor control and muscular strengths.
During the first stages or years, Children start to experience changes in all aspects of their motor development; however it is possible to notice some common distinctiveness of the child’s progress and to separate out certain abilities. Although children fluctuate considerably in the pace of their progress, the common outline of early motor growth tends to be extremely similar for all (Jersild, 1940).
The development of motor activities interlace with changes in gross bodily dimension, the dimension of various parts of the body, and in bodily mechanics. The standard newborn child is about 20 ½ inches long. During the first year, his length enlarge by over a third, by the age of five years, he will be in relation to double as tall as he was at birth. During the stage of physical growth there in addition ongoing changes in the proportions of the body (Jersild, 1940).
Different parts of the body grow at different levels and get to their estimated utmost at different times during the stage from early childhood to maturity. There is not only a degree of difference of growth for different parts of the body, but a degree of difference growth pattern may show variations from individual to individual (Jersild, 1940).
I believe this is a topic which is over and over discussed and that it is essential in our development. Also it is important to recognize that the development of motor skills depends a lot on hard work and that persistence effort alone is not sufficient to master any skill. In any movement made by any individual there is collaboration among a variety of muscles. The untrained person may have a slight control of the mechanism of a difficult movement that there is little or no coordination, with consequential discomfort, while the trained person may be able to carry out his acts with great proficiency and accuracy (Morgan, 1941).
Also individuals may engage in activities which movements of diverse types function in conjunction. No movement requiring excellent coordination is possible without relative fixation of the bigger supporting muscles. Rapid walking, for example, consists of rapid expansion and bending of the legs, at the same time that a straight stance is being retained by the trunk (Morgan, 1941).
Fixation movements are just as essential for skilled activity as are rapid actions. However, in many occasions efficiency is inferior and the achievement of skill slow down because the right combination of movements is not used. When there is a choice between the rapid movement and the controlled movement, the rapid type of movement has great advantages (Morgan, 1941).
As indicated before, while a person get older there are some changes in the speed, precision and strength which motor operation are completed. These changes occurring in both acts gross and fine motor skills are vital in human development as many of our activities in life depend upon the competent implementation of motor acts (Wolfe, 1938).
Motor skills movements
Motor Skill means the existence of certain connections by means guiding sensations arouse appropriate movements. Practice means the formation of such connections. A skilled movement may commonly be divided into the inferior adjustments with which it starts and the advanced adjustments which come into play in response to the guiding sensations (Thorndike, 1922).
Motor skill is consequently in no way a matter of limitation of movement itself. It involves also the ability to receive and attend to the differences in sensations which are the guides to the improved adjustments, and, most important, the ability to make connections between sensations and movements, to get rid of the unnecessary and undesirable movements. These abilities get better with maturity, and with training, provided the successful connections are satisfied by ensuing satisfaction.
Skill in movements is in no way mainly a subject of the arms and hands. The movements of the vocal chords in speech and the eyes in focusing objects into clearest vision are the most precisely adjusted movements we have to make. According to Thorndike, (1922), the movements of the facial muscles by which interest, enjoyment, passion and the like are articulated are often exceptionally slight and in the case of actors may be the result of extended sustained practice. These skills are improved by:
Intentionally following certain guidelines that can be learned by simple practice.
By involuntarily reducing ineffective and highlighting efficient connections in the course of practice.
The first aspect, the learning by explanations, may be called the achievement of Form and the second aspect, the learning by trial and error, may be called the acquisition of Execution. An example will be a golf player may have taught completely the right way how to hit the ball, how and where to stand and how to hold the club. This is what is called learning form. But the real associations between the sight of the ball and the exact movements essential to hit it a hundred and sixty yards must be patiently developed by the “try and trying again” method (p. 302).
Motor skills and habits
Habits and skills are plans that were at first voluntary but that have become somewhat inflexible, involuntary, and automatic. Once the plan that controls a series of trained actions becomes permanent through over learning, it will work in much the same way as a native plan in instinctive behavior. The explanation of the circumstances in which various skilled mechanisms will be generated, or released, is much the identical in both cases. The new dilemma that we have to reflect on is when we go from instincts to habits and skills concerns how learned plans become something more mechanical or automatic (Miller, Galanter & Pribram, 1960).
When a grown-up person is in the position to obtain or learn a number of new skills, he/she usually start with a set of instructions. Another person, either verbally or by illustration, indicates in steps what he/she is expected to do. Having just the basic approach in verbal cues does not indicate that the person or learner can appropriately expand and/or carry out the strategy on the first attempt to execute the plan. There has to be a type of commitment between the trainer and the learner. It is easy for the trainer to explain the general approach, but hard for him to communicate the thorough strategy that should be used. On the other hand, the learner, in each of the muscular actions implicated can be completed separated, but it is difficult for him/her to combine that strategic information into a bigger motor component that will diminish the distinction between his/her projected and his/her actual performance (Miller et al, 1960).
In order to be able to perform the plan the learner must find many small, combined acts not specified in the trainer’s original explanation of the plan. The general approach given by the trainer does not indicate anything about the activities of individual muscle groups, the trainers “knows” these combined acts because he knows how to perform the action expected, but they are guarded in implicit or unspoken, rather than explicit and communicable. Therefore, the trainer is working in the direction of what is intended in his efforts to communicate the plan, while the learner is working in the direction of what is intended in his efforts to carry it out (Miller et al, 1960).
Since a learner have to find out these little tricks that can connect the consecutive parts into a easily running skill, it might come into view that he/she is simply attaching one activity to the next, not building an arrange plan. However, if the skill is merely an attachment of reflexes, each one tide to the next, then it is hard to realize why sometimes the trainer’s method was or was not satisfactory. Unless there is some over-all model to the skill, the trainer might see a pattern one way and the student sees it in another (Miller et al, 1960).
The explanation of the task can be changed in a variety of ways in an attempt to come across with a series of motions that accomplishes the result proficiently, with a smallest number of movements and in smallest amount time. When people have and spent time to develop the skill themselves, by following a certain plan to guide the gross actions even though an inefficient plan, they will find a way to begin to generate the elements that will produce the skill. Discovering these elements is in essence an experiment of the competence of the strategy. Once a strategy has been developed, an unusual form of action become possible, and is when that the person has learned or comprehend the skill that he/she is to do (Miller et al, 1960).
In most normal conditions, the development of skills involves the building of a sequence of behavioral components guided by its own plan. But for the most part the trainer must rely upon showing and demonstrating the sequence until the learner is able and feel comfortable with the task.
Animals can achieve skills as well, obviously, without memorizing verbal descriptions of what they are supposed to do. When a person train an animal to carry out a series of responses in order to accomplish something, the approach is not processed in the animal’s memory. Only the trainer needs to know who the plan works and the expected outcome. The animal is required simply to come up with even changes that attach one action to the next (Miller et al, 1960).
The verbal expression of strategies of a learner may get the same result as the involuntary, habitual strategies of a professional, in which a sense could distinguish as being the “same” plan. But the learner’s plan is carried out in a way that is voluntary and transmittable, while the trainer’s version of the plan is involuntary and, usually, protected (Miller et al, 1960).
It can be said that the development of motor skills frees the trainer from the need to work with bigger components of the original plan. The proposition of this approach toward skills and habits is that man is understood to be capable of strengthening his own “instincts.” It is said that animals come with strategies already wired in; man wires them in intentionally to serve his own purposes. With this said, when the plan is very much over learned, it becomes almost as involuntary, as resistant to change depending upon its outcome (Miller et al, 1960).
Dynamic systems theory
Dynamic systems theory is the process in which infants develop motor skills by perceiving and acting. The infants should percive something in the environment that stimulates them to act so they adjust their movements. Motor skills symbolize resolution to their goals. Every time an infant is motivated or stimulated to accomplish something, he/she will generate a new motor skill or behavior based on the body’s physical abilities and the environmental support (Santrock, 2008).
According to Santrock (2008), “â€¦motor development is not a a passive process in which genes dictate the unfolding of a sequence of skills over time. Rather, the infant actively puts together a skill in order to achieve a goal within the constraints set by the infant’s body and environtment” (p. 152).
In order to explain better how dynamic system theory applies to motor development, Santrock (2008) stated we need to understand reflexes, gross motor skills and fine motor skills.
These are involuntary acts that our body produces in response to something. Most of the time this response comes automatic without thinking about it. According to Santrock (2008) there are several types of reflexes; rooting reflex, sucking reflex, moro reflex, and grasping reflex.
Rooting reflex – is when the infant’s cheek has been pat or touched and the infant moves towards the side touched in an effort to find something to suck.
Sucking reflex – is when infants automatically find an object and place it in their mouth to suck at it.
Moro reflex – this is a response from unexpected noise (loud) or when the infants believe they are falling. It also considered as an unlearned fear.
Grasping reflex – when an individual touch the infant’s palm and he/she grasp the finger tightly.
Gross motor skills
Gross motor skills involve basically all the muscle of the body that facilitate tasks such as walking, sitting, lifting, and throwing objects. Santrock (2008) divides gross motors skills into different categories; development of posture, learning to walk, first year (milestones and variations), and development in the second year.
Development posture – is a process in which posture is connected with sensory cues in the joints and muscles. Although newborns cannot control their postures they learn how to control their heads and even sit within the first two months.
Learning to walk – the process in which the infant can alternate leg movements along with postural control. The infants can take on in alternating leg movements within the first six months.
First year – during this time the infant will discover, experience and develop important gross motor skills which will end with the accomplishment to walk easily.
Second year – due to the infant accomplishments during the first year, the infant start experience a sense of independence to move and he/she start exploring new venues.
Motor skills generally develop together as most actions rely on the coordination of gross and fine motor skills. Gross motor skills build up reasonably in a short period of time. The majority take place during childhood. Nevertheless, some people due to profession (police) and/or hobbies (hikers) that employ high level of stamina may spend a lot of time working on their level of muscle and body coordination and gross motor skills (Gross motor skills, 2010).
Gross motor skills development is ruled by two doctrines that that control physical growth as well. Head to toe development relates to the way upper parts of the body develop starting with head and finishing with lower parts. The other doctrine refers to the trunk to extremities. First, the control of the head is gained, followed by shoulders, arms and hands. Second part developed is the upper body control followed by hips down to the legs (Gross motor skills, 2010).
Fine motor skills
Fine motor skills involves the small muscles of the body which help us with primary functions such as grasping objects, writing, drawing, and tide shoe laces. Logsdon (2010) stated that “fine motor skills are important in most school activities as well as in life in general. Weaknesses in fine motor skills can affect a child’s ability to eat, write, and perform personal care tasks such as dressing and grooming (para 2).
Fine motor skills involve the use of hands, which usually develop over a period of time. It starts with primordial gestures such as grabbing objects to particular activities in which hand-eye coordination is needed. Fine motor skills engage a sophisticated utilization of small muscles controlling all fingers of the hand.
Developing such skills will allow us to complete complex tasks such as writing, drawing, tie bows or strings. According to Essa, Young & Lehne, (1998), “During the infant and toddler years, children develop basic grasping and manipulation skills, which are refined during the preschool years. The preschooler becomes quite adept in self-help, construction, holding grips, and bimanual control tasks requiring the use of both hands” (p.127).
Dynamic systems theory
Relevant framework for performance-oriented sports biomechanics research
According to Glaziera, Davids, Bartlett, (2003), Dynamical system theory has surfaced in the area of sciences as a practical structure for a representation of athletic performance. From a dynamical systems standpoint, the human system is a very complicated network of mutually dependent systems (para.1).
Movement patterns come out through a general process of self-organization found most likely in physical and biological systems. Throughout the research, theorists declare that the number of biomechanical degrees of autonomy of freedom in the motor system is radically condensed though the development of coordinated structures or provisionally gathering of muscles complexes (Glaziera et al, 2003).
They also found a paradoxical association between stability and variability making clear why experienced athletes are capable of equally persistence and change in motor productivity during sport performance. Definitely, inconsistency in movement behaviors allows performers to discover task and environmental restrictions in order to gain stable resolutions over time and improve motor learning (Glaziera et al, 2003).
Researchers have disputed that dynamical systems theory applied to motor control is a significant structure for performance oriented sports biomechanics research. They have projected that dynamical system theory offers an exclusive opportunity for motor control theorists and bio-mechanists to work in conjunction to search or investigate alternative research designs and other techniques that will eventually improve our knowledge of the processes of coordination and control in our movement system, guiding to enhance motor performance (Glaziera et al, 2003).
Motor Behavior Research in Schizophrenia
This topic about motor abnormalities on people with schizophrenia raised a lot of interest on me as schizophrenia has become one of my areas of expertise. I have always been intrigued as of why these deviations happen even when the person has not been taking medication for a long period of time.
Motor irregularities play an important, if not fully understood, role in the cause, development, and effects of schizophrenia. The investigation started focusing on deviant speech in schizophrenia, so-called formal thought disorder, and “loosened associations.” The attention- deficit hypothesis alleged to make clear these disturbances in its clarity (Manschreck, 2003).
The challenge facing researchers dedicated to discovering the attention-deficit hypothesis as a comprehensive representation for schizophrenia was the degree to which this hypothesis was useful in understanding psychopathologic phenomena. This led to study of the motor dimension of schizophrenia. Motor abnormalities have long been experimented on, often with outstanding representation (Manschreck, 2003).
These abnormalities fall into a range of subcategories, including posture, walk, and voluntary and involuntary motor movements. Regardless of the well clinical knowledge, motor abnormalities were neglected during a great deal of the early 20th century and have not been effectively clarified. During the 19th-century psychiatrists identified motor abnormalities in schizophrenia recording cases leaving well documented understanding of their relationship to schizophrenia. Before the arrival of neuroleptic treatment, atypical movements were studied and recorded. These movements were for the most part concerted among patients with diagnoses of schizophrenia and with remarkable distinction, almost not present among patients with other brain disorders (Manschreck, 2003).
Other than being secondary results, these features were associated with several natural accounts variables, particularly an inferior prognosis and restricted social recovery. Another trait of motor abnormality that called the attention of researchers was the outstanding overlap of descriptive terms for verbal and motor pathology in schizophrenia, such as poverty of movement and poverty of speech or motor blocking and thought blocking. This investigation association recommended that motor abnormalities might be connected with verbal deviances which are not yet understood, and suggested a potential hypothesis; that formal thought disorder and motor pathology might be related in schizophrenia (Manschreck, 2003).
Abnormal voluntary movements (AVMs) are recurrent in people experiencing symptoms of schizophrenia. They are different and unique and can be distinguished from drug-induced movements. Abnormal voluntary movements are related to other specific mental illness features, including memory, thinking, emotional blunting, neurologic signs, and imaging characteristics (Manschreck, 2003).
Researchers made a series of assessments which included spontaneous motor activities using a rating scale designed to identify abnormalities. Also examined a series of complex motor tasks judged according to level of disorganization, delayed response, length of completion, and persistence was undertaken to elicit abnormalities. Drug-induced effects were evaluated with the Abnormal Involuntary Movement Scale (Manschreck, 2003). The results of this study showed the following:
1. Thirty six of thirty seven patients with schizophrenia demonstrated disturbed voluntary movements. There was some predisposition for the paranoid subtype cases to show to some extent a smaller amount of severe levels of abnormality.
2. The patients with mood disorders demonstrated a smaller amount frequent and not as much of severe evidence of abnormality.
3. Voluntary motor disturbances were connected with a formal thought disorder, emotional blunting, and neurologic signs. Additionally, they were not linked with indication of drug-induced motor effects. In fact, the analysis sustained the conclusion that antipsychotic medication had a slightly positive impact, reducing the incidence of such movements.
In reality, the forms of motor disturbance identified were not distinctive of drug induced motor effects. To a certain extent, these disturbances fell into three general categories:
Disruption in the efficiency and coordination of movements.
Intermittent repetitive movements
Disturbances in performing chronological actions. Motor abnormalities were recurrent, but hardly ever dramatic in their presentation.
The motor abnormalities identified in the study were connected with formal thought disorder. This means that speech deviance was linked with deviance in the motor area. As assumed, they identified a possible connection between formal thought disorder and motor anomalies. On the other hand, their major finding was the extent to which they were able to find the presence of fundamental schizophrenia motor abnormality when most researchers alleged that motor deficiencies resulted from neuroleptic medication (Manschreck, 2003).
Motor abnormalities although not fully understood, play an important role in the pathogenesis of schizophrenia. Abnormal voluntary movements (AVMs) are frequent in schizophrenia. They are different and can be consistently notable from drug-induced movements. There are now several forms of motor abnormalities known to be associated with schizophrenia. The connection surrounded by the different forms has not been adequately investigated. Patients with atypical involuntary movements had greater indication of voluntary motor abnormality, greater indication of formal thought disorder, negative, and memory disturbance. It is also remarkable how patients with abnormal involuntary movements also showed lower pre-morbid intellectual ability (Manschreck, 2003).
The localization of motor performance is condensed in schizophrenia and is linked with increased thought disorder, memory disturbances. Involuntary movements are also recurrent and have been connected with drug treatment, aging, and the disease process of schizophrenia. Those movements are associated with the same pattern of mental illness features but further severe level than the movements that are portrayed as “voluntary” movements (Manschreck, 2003).