Kin 365 Exam 3
How is anaerobic endurance measured? Aerobic endurance?
- Assessing Anaerobic Performance: The Quebec 10 s and the Wingate 30 s all-out rides on a bicycle ergometer and the Margaria step-running test are common tests that provide scores in total work output, mean power, or peak power. Total work output indicates how much absolute work an individual can do in a 10 s or 30 s time period. - Assessing Aerobic Performance: Measured through cycling on an ergometer or walking or running on a treadmill. Aerobic exercises are graded, meaning they increase the workload in stages. A common measure of fitness for endurance activities is maximal oxygen uptake (the maximum volume of oxygen the body can consume per min)
What factors tend to limit the aerobic endurance of older adults? Anaerobic endurance?
- Cardiac: The major structural changes in a aging heart include progressive loss of cardiac muscle, a loss of elasticity in cardiac muscle fibers, thickening of the left ventricular wall, and fibrotic changes in the valves. The major blood vessels also lose elasticity. - Respiratory: Elasticity of the lung tissue and chest walls declines with aging. Therefore, older adults expend more effort in breathing than young adults. - Muscle mass: The decline in maximal oxygen uptake is probably related both to loss of muscle mass and the ability of muscles to use oxygen.
How do infectious diseases affect endurance? What strategies are best followed when one begins training after an illness?
- Short term infectious diseases, such as influenza, mono, and chicken pox, generally reduce an individual's working capacity. - When training following an illness, activity must be adapted to the new constraints the individual is facing. Plan the limits of activity carefully, set expectations accordingly, and monitor the participant closely.
At what points in the life span can individuals improve aerobic endurance with training? Do those who build higher endurance in youth realize a lifelong benefit? What types of studies best answer this question? Why?
- The anaerobic systems of older adults do not produce energy as quickly as those of younger adults; this decline is likely associated with loss of muscle mass. At the same level of exercise, older adults accumulate by-products of energy metabolism sooner than young adults do. It is not clear, however, whether anaerobic power and capacity necessarily decline as adults grow older. Those engaged in lifelong intense training showed no deterioration in anaerobic performance. Because any loss of muscle mass in older adults is likely to affect anaerobic performance, a lack of training in anaerobic tasks to maintain conditioning logically would affect performance.
What are the sex differences in anaerobic and aerobic endurance over the life span? To what factors might these differences be attributed?
- Total work output scores improve over the entire adolescent period in boys but only until puberty in girls, perhaps reflecting the patterns of muscle growth in the sexes. or sociocultural views of appropriate activities for girls. Accounting for differences in muscle mass, however, does not entirely eliminate the differences in anaerobic performance that favour boys. - Preadolescent and adolescent boys have demonstrated improved anaerobic power with anaerobic training - Improvements with training might be associated with metabolizing energy reserves more efficiently, therefore improving anaerobic capacity. - Less is know about girls, however, small improvements have been noted in prepubescent girls with both cycle and sprint running training - Boys and girls are similar in maximal oxygen uptake until about age 12. - After this age, maximal oxygen uptake plateaus in girls but continues to increase in boys. The increase with age is related to growth of the musculature, lungs, and heart. - Men gain more lean body mass and less adipose tissue than women. Women are similar to men in maximal oxygen uptake, but when adipose tissue is included, women have a lower maximal oxygen uptake. Women also tend to have lower hemoglobin concentrations than men.
How can a teacher or therapist manipulate task constraints to help a child acquire the skill of galloping?
- first take a side view and note where the trailing foot lands in relation to the lead foot. The extent of vertical lift is also clearly visible from the side. Arms can be viewed from any angle. In proficient galloping the trailing foot lands alongside or behind the lead foot, the flight pattern is low and the arms are free to swing rhythmically, clap, or engage in another activity. Note whether a child can lead with the dominant leg only or with either leg.
What patterns do children's developmental reaching go through?
- newborn- asymmetrical, random arm movements - 2 months- bilateral flexions and extensions of the arms - 4 months-infants can reach bilaterally for an object - 5 months- infants reach bilaterally for an object but just one hand grasps, bilateral movements start to decline - 7 months- infants reach both bimanually or unimanually depending on the size weight and shape of the object.
What factors contribute to an infants poor eyesight?
- the small size of the eye itself - immature curvature of the cornea - the immaturity of the fovea - the immaturity of the visual cortex of the cerebrum
Describe the constraints that may act as rate controllers for specific locomotor activities.
-strength -balance -fear of falling -disease -coordination
For 4 of the infantile reflexes in table 6.1, describe either a survival function or a purpose later in life.
1.) Asymmetrical tonic neck: In utero the ATNR provides the necessary stimulation for developing muscle tone and the vestibular system. It assists with the birth process, providing one of the means for the baby to "corkscrew" down the birth passage. ATNR also provides training in hand-eye coordination. 2.) Moro: may be a survival instinct to help the infant cling to its mother. If the infant lost its balance, the reflex caused the infant to embrace its mother and regain its hold on the mother's body. 3.) Doll eye: keeps the infant's focus of something constantly with its visual field. 4.) Rooting: helps infant find food.
What is the typical method for studying intermodal perception?
1.) Integrational perspective: the energy reaching the different senses is of different forms -- light, sound, temperature, and so on -- and each sensory system yields a unique sensation. 2.) Unified perspective: sees the senses as united in bringing information about events, but through different modalities. The nervous system is structured for multimodal perception so that, from the start, perceptions are coherent in time and space.
What is retinal disparity?
Also involved in our depth perception is what is referred to as retinal disparity. This means that any object in our vision is viewed from a slightly different angle from each eye. The fact that our eyes are approximately 2 1/2" apart also gives our vision a binocular parallex, in that two separate images are sent to the brain whenever we look at something.
What are the various aspects of auditory perception, and what information about the sound source does each provide?
1.) Location: newborns turn in the direction of a sound, and they rapidly improve in their ability to locate sound during the first year. 2.) Differences: Infants as young as 1-4 months can discriminate between basic speech sounds, but children between 3 and 5 years experience increasing accuracy in recognizing differences in sounds. 3.) Patterns: Auditory patterns are nonrandom, temporally (time) - ordered sound sequences. 3 properties of sound give rise to auditory patterns: - time - intensity - frequency Infants as young as 2-3 months react to changes in the temporal pattern of a tone sequence, showing they perceive temporal patterns.
According to Thelen, what rate controlling factors come into play with locomotor development?
1.) Muscle strength- both in the trunk and leg extensors, both necessary for upright posture. 2.) Balance- necessary when shifting weight from one leg to another. Note that walking is made possible at an earlier age when parents hold the child's hands thus eliminating the need for balance.
What qualitative developmental changes are shared by throwing and overarm striking? Why might both skills change in these ways?
1.) Side arm action: transferring weight to rear foot, taking step forward, and transferring the weight forward at contact. 2.) trunk rotation: first use block rotation before advancing to differentiated rotation. 3.) Vertical plane to oblique plane to horizontal plane: Eventually they obtain a longer swing by holding their elbows away from their sides and extending their arms just before contact.
What are the 3 categories of motor milestones?
1.) Stability or postural control 2.) Locomotion 3.) Manipulation or manual control
What are the 2 categories balance is placed into?
1.) Static balance- is the ability to maintain a desired body posture or position when your body is stationary. 2.) Dynamic balance- is keeping your desired body position while your body is moving. Both static and dynamic balance are used in a lot of movement activities. For example, a diver uses static balance as he stands poised and relatively motionless on the tip of the diving board before a dive. His body then goes through a number of rotations as he propels his body toward the water, relying on dynamic balance to maintain his desired body position.
What are some individual constraints an infant possesses that effect motor milestones?
1.) maturation of the CNS 2.) development of muscular strength and endurance 3.) development of posture and balance 4.) improvement of sensory processing
From the perspective of the dynamic systems approach, what locomotor development depend on?
1.) the body's systems 2.) the task 3.) the environment in which the task is attempted
What seems to be the role of experience with self-produced locomotion in the development of perception? Which aspects of perception are most affected?
A study using kittens found that passive kittens failed to accurately judge depth and failed to exhibit paw placing or eye blinking when an object approached. Evidently, self-produced movement is related to the development of behaviour depending on visual perception. There is also evidence that there is more brain growth and more efficient nervous system functioning in those with perceptual motor stimulation above the norm. Infants will also avoid cliffs/height. Thus, self-produced locomotion appears to facilitate development of depth perception. Other studies support the suggestion that locomotor experience facilitates development of spacial perception. E.g. infants first learn to retrieve an object hidden behind a cloth; understanding that the object still exists even if hidden. Surface perception and affordance perception (what the environment permits us to do) also appears with locomotion.
What are some of the ways in which humans can move from place to place (without equipment)? Which ones are not currently observed in adults? What are these locomotor forms rarely used?
Adults rarely use hopping to move around, yet to become a skillful mover, an individual should develop hopping skills during childhood.
What is the difference between power and capacity in the measurement of anaerobic and aerobic endurance?
Aerobic power = is the rate at which long-term oxygen demand is met during prolonged activity. Aerobic capacity = is the total energy available to meet the demands of prolonged activity.
In relation to the dynamic systems perspective, how does vision impact motor development.
An infant's blurred vision starts to improve between 6 to 18 months. Think about what the baby is starting to do during this particular developmental period. They are learning to crawl, and then creep, starting to physically explore their environment. From a Dynamics Systems perspective, vision then acts as a rate controller, controlling, at least initially, a child's rate of mobility. By the end of the first year of life, a baby's visual acuity is between 20/100 and 20/50. By five years, it is about 20/30 and by age 10 ( barring any other visual problem) it is at adult levels, 20/20.
What are the major developmental trends we see in children as they become increasingly proficient in catching?
Arm Action: Step 1- little response Step 2- Hugging Step 3- Scooping Step 4- Arms give Hand action: Step 1- Palms up Step 2- Palms in Step 3- Palms adjusted Body Action: Step 1- No adjustment Step 2- Awkward adjustment Step 3- Proper adjustment
What did Arnold Gesell and Louise Ames observe in children?
Arnold Gesell and Louise Ames (1940) looked at the contralateral pattern or cross lateral flexion and extension in infants. They noted that newborns first demonstrate bilateral flexion (e.g. bend both arms at the same time). This is gradually replaced by unilateral flexion of the limbs (e.g. one side of the body at a time). What Gesell and Ames noted, however, was that just prior to creeping, babies commonly rock back and forth on their hands and knees. This once more is bilateral movement. This movement pattern needs to take place before the child can progress to the cross-lateral pattern necessary with creeping. This pattern: bilateral, unilateral, bilateral, cross-lateral, where an infant reverts back to a movement pattern previously outgrown is called reversion or regression.
Can prepubescent children improve anaerobic endurance with training? Aerobic endurance? Explain your answers.
At any age, anaerobic performance is related to: - body size, particularly fat-free muscle mass and muscle size - the ability to metabolize fuel sources in the muscles - quick mobilization of oxygen delivery systems
Do we know whether being active as a child or teen makes a difference in fitness levels in adulthood? On what do you base your answer?
Despite limited research in this area, the evidence suggests that regular activity in childhood has positive lifelong benefits. Promoting an active lifestyle with children and youths could predispose them to be more active as adults.
What factors interplay in balance?
Balance depends on information coming in from a number of sensory systems. Our balance depends upon our visual, kinesthetic systems and also from our auditory system and inner ear or vestibular apparatus. Balance depends then on intersensory integration.
Why an infant Might be delayed in attaining a motor milestone. Describe how both task and environmental constraints can have a profound effect on the emergence of motor skills.
Be careful when attempting to assess the neurological status of an infant. Each infant develops as a result of interacting individual, environmental, and task constraints. This means that one infant may continue exhibiting reflexes after another of the same age has stopped with any pathological condition being involved. Reflexive responses are very sensitive to environmental conditions. If you change an infant's body position or provide him with a stimulus that is different, you won't get a response. An infant may be delayed due to a pathological cerebral condition.
Who studied the maturational perspective and what was their view of motor milestones?
Both Gesell and Ames as well as Shirley and Bayley were maturationists, in that they believed that all these motor milestones you've been reading about are dependent on the brain's development.
What appears with cortically controlled voluntary movement?
By about the fourth week of life, we begin to see the first signs of cortically controlled voluntary movement. These first signs of movement are slight and involve movements of the head, neck and eyes, but these are, nonetheless voluntary movements which increasingly become more prevalent and more useful in helping a child explore her environment. By the end of the first year of life, there is almost complete voluntary control over movement.
How do children react to varying ball speeds?
Children are inaccurate with slow velocities because they respond too early. Perhaps children prepare for the fastest speed an object might travel and then have difficulty delaying their responses if the speed is slow. Also, the preceding speeds might influence young children more than they do older performers. If the previous moving object came quickly, young children judge the next object to be moving faster than it really is.
What is an affordance? What does the notion of affordance have to do with adapting equipment size to the size of the performer?
Consistent with the notion of direct perception, developmentalists with an ecological perspective believe that we directly perceive what the objects and surfaces in the environment permit us to do, given our own capabilities. That is, we perceive affordances. Stair climbing provides a good example of an affordance. A set of stairs with an 8 in rise between steps does not afford alternate-step climbing for an 18 month old as it does for an adult.
What's the difference between creeping and crawling?
Crawling: (4-6 months) Crawling actually precedes creeping in the progression of prone locomotion. Crawling is seen as the first attempt at purposeful locomotion. It is a sliding forward movement on the abdomen, where arms reach out in front and pull back toward the feet. The legs aren't really used much in early attempts at crawling. Creeping: (7-9 months) Creeping evolves from crawling and differs from the preceding movement in that the legs and arms are used in opposition to each other. The infant is up on all fours (hands and knees). The most efficient form of creeping is when infants use the contralateral pattern. This involves the right leg moving forward as the left arm reaches out. The homolateral pattern is when the right arm reaches forward, so too does the right leg.
What are some environmental constraints in developing motor milestones?
Culturally defined parental handling practices can alter the rate at which an infant attains motor milestones. For example, an infant born to a new mother may experience "first child syndrome". This is where first-tie mothers hold their infants for long periods and avoid putting the infants on their stomachs for a long time. These periods of prolonged holding result in delayed onset of certain motor milestones such as crawling.
Explain Delacato's hemispheric dominance theory.
Delacato perhaps more so than Kephart has contributed to the controversy surrounding the term perceptual motor. Like Kephart, Delacato believed that involvement in certain activities would help with intellectual development. Delacato however, believed that the development of hemispheric dominance was critical to optimal cognitive functioning. In other words, he believed that one hemisphere of the brain must maintain control or dominate the other for certain behaviors to occur. Delacato also believed that many intellectual problems could be overcome by reenacting early movement skills that were either missed or omitted in early motor skill development. To reenact activities, Delacato recommended a process known as patterning. In other words, Delacato believed that if say a person missed the "creeping" stage in their motor development, this would then lead to learning difficulties later in life. He would then have that person "go back" to the creeping stage to "re-learn" how to creep, thus assisting their current learning process! Kind of weird. Delacato also believed that reducing fluids, sugar and salt consumption and "breathing in expired air" could also improve cognitive functioning! There may be a few of Delacato's proponents still around, but most experts agree that his techniques are unsubstantiated and extremely questionable. To say the least. There have been a considerable number of individuals who were "patterned" but showed no intellectual improvement. Any slight cognitive enhancement observed may have simply been due to the extra social contact "patterning" participants may have received. In 1993, the American Academy of Pediatrics published a position statement stating their opposition to the Doman-Delacato Patterning treatment. In it, they said that they were aware of only one scientific investigation in over 20 years that has indicated any cognitive improvements in patients receiving the patterning treatment.
Explain "reaching" in terms of locomotor development.
During the first four months, the infant doesn't make any definite reaching movements toward objects. An infant will, however, make a visual connection with an object and make motions in the object's general direction. These vague motions toward an object are called prereaching. Moving objects tend to illicit more prereaching actions than stationary objects. This is why most mobiles you see to hang above cribs, move as opposed to being stationary.
What changes in visual sensation occur during infancy? During childhood?
During the first month of life, the visual system provides the infant with functionally useful but unrefined vision at a level approximately 5% of eventual adult acuity. The newborn's resolution of detail is such that she can differentiate facial features from a distance of 20 in. At about 6 months of age, as infants' motor systems are ready to begin locomotion, their visual systems perceive adequate detail to assist them in the task. Visual sensation continues to improve during childhood. 5 year olds have visual acuity of about 20/30, and by age 10 children without a visual anomaly score at the desired level of 20/20.
What changes in auditory sensation occur during infancy?
Fetuses respond to loud sounds, but perhaps this response is actually to tactile stimuli -- that is, vibrations. The newborn's hearing is imperfect partly because of the gelatinous tissue filling the inner ear. The absolute threshold is about 60 decibels higher for a newborn than for an adult. So, a newborn can detect only an average speaking voice when an adult can detect a whisper. Newborns also do not discriminate changes in the intensity of sounds (differential threshold) or in sound frequencies as well as adults can. The gelatinous material in the inner ear is reabsorbed during the first postnatal week so that hearing improves rapidly. By 3 months, infants hear low-frequency sounds very well but do not hear high-frequencies as well. By 6 months, infants' hearing is similar to that of adults.
Explain posture control over the stages.
Gaining upright posture is important in a child's growing repertoire of movements because it frees up the hands for even greater explorations! If assisted, infants can sit as early as 3 months (they have little lumbar control so need support to the lower back and abdomen). By five months, they can sit without support due to greater lumbar control, but you'll note that the infant will still need to lean forward and support this position with their hands planted in front of them. By eight months, infants can sit without assistance or support. By nine months, infants start to pull themselves up from a sitting to a standing position with a wide base of support (legs apart) and using an external object for support (like a coffee table). Infants typically can stand erect in preparation for walking between 11 and 13 months.
Explain the theories of Newell and Delacato and their key concepts.
Historically, theorists have had a particular impact in the perceptual motor area, particularly in the realm of perception-action. Much of this initial work stemmed from understanding children with learning disabilities and the assumption problems with learning stemmed from perceptual deficits. Newell C. Kephart was one of these earlier theorists with his Perceptual Motor Theory. Another was Delacato with his theory of hemispheric dominance. The key principles linking both of these earlier theories was that: 1.) cognitive development can be enhanced through movement 2.) both have had a major impact on the education of children 3.) both theories have created a fair amount of controversy
What changes to balance occur with aging?
It becomes more difficult to balance as we age. Those over the age of 60 tend to sway much more than younger adults when balancing on one foot. What is also found is that older adults' muscles tend to react more slowly to regain balance and muscles of the upper leg react first rather than those of the lower leg. This is the reverse of the muscular response of younger adults. Much of this muscle imbalance may be due to the atrophy of type II fast twitch muscles found predominantly in the lower limb. There is a lot of research in this area. Too much for the scope of this class, but a lot of focus on how the fear of falling in older adults can influence gait or how elders walk.
What do infantile reflexes in utero tell us?
Infantile reflexes both in utero and postnatal tell us that babies, from a very early stage, have kinesthetic receptors that respond to their bodies' position in space. Turn a baby's head, and the body instantly responds even in newborns with the head righting reflex. We can also see the principle of cephalocaudal growth in how the cutaneous receptors develop from oral, genital-anal, palmar then finally plantar development.
What changes in kinesthetic perception change in older adulthood?
It helps here to view this from the ecological or from the perspective of intermodal perception. We perceive things around as and respond based on many aspects of our sensory input. And as we have learned, decline may be associated with loss in different sensory systems at different times throughout development and into the aging process. Static joint position and sense about lower limb joint location and position deteriorates with age along with the ability to detect joint motion or kinesthesia. Aging is also associated with greater challenges with picking up proprioceptive feedback during more complex motor tasks. One study looked at 12 performance based tests of muscle strength, balance, gait, somatosensory discrimination, and reaction time; all of which showed that these declined increasingly with age. Interestingly, the vibration threshold was the most rapidly affected by age. Overall, changes in proprioception become more noticeable after the age of 65 years with the slowing and disruption of proprioceptive input seen as the largest determinant of balance ability in adults over the age of 80.
Explain Kephart's perceptual motor theory.
It was Kephart who was originally credited with initiating the emphasis that some educators now place on using movement to improve student's academic performance. Kephart believed that learning problems were the result of not being able to integrate present stimuli with stored information about past stimuli. In other words, he believed that children with learning difficulties have problems with sensory integration which is a critical part of the perceptual motor process. Kephart also theorized that children with learning problems had trouble with the feedback process which of course is necessary to correct any errors in learning, and in movement skills. So Kephart's basic premise was that if you put students with integration and feedback problems through a specified movement program, then this in turn would improve their academic skills like reading and spelling. He believed that focusing on perceptual motor tasks like balance, eye-hand coordination, laterality, directionality and spatial awareness would enhance a person's cognitive as well as motor functioning. The biggest opposition to Kephart's theory is that there is no empirical data or scientific evidence that can support his claims. Initial studies that were conducted in this area showed no or very little correlation between perceptual motor development, perception and cognition. This is however now viewed with a more favourable lens as will be discussed below.
Explain the development of balance.
Its generally understood that balance improves steadily from about age 3 to the late teens (age 19). Again, a lot of this improvement is based on the balance task itself. Ledept and Bril (2009) have looked at the development of balance associated with walking in toddlers Ledept and Bril (2000). Both the onset of walking (as well as the decline of walking in older adults) is dependent on many factors, including upper body control and the stability of the head, arms and trunk. So much of our ability also depends on the task we are doing; egmoving forward requires a different frame of reference for your ability to stay upright. Research has also examined how children learn to balance using a balance beam. Children start with the shuffle step (where one foot always stays in front of the other), followed by a mark-time step, ending with the mature alternate step pattern. What is noted is that as the balance beam narrows, children tend to revert back to a shuffle step. Think how different your balance is depending on the level of risk if you were to fall. How would your movement pattern change if what you were balancing on was suddenly suspended 100 ft. in the air?
What is lateral awareness?
Lateral awareness is the correct labeling of the two sides of the body. This is usually not fully developed until about age seven. Children develop the concept of front/back, up/down, beside/in front, all those Sesame Street concepts first (@ age 3) before they can grasp the concept of left/right. Most children will gain lateral awareness by age 7 and respond with 100% accuracy by age 10.
What distinguishes kicking from punting?
Like throwing, kicking projects an object; unlike throwing, however, the kicker strikes the object. The ballistic skill of punting is mechanically similar to kicking, yet punting tends to be more difficult for children to learn. To punt, a child drops the ball from the hands and must time the leg swing to the dropping ball.
Do infants learn to reach for objects by better matching their hand position to the seen location of the object, or by better controlling their arms?
Many developmentalists proposed that reaching and grasping required seeing both the object and the hand in the visual field so that vision and proprioception could be matched. Bruner further suggested that infants build a system of visually guided arm movements from initial, poorly coordinated movements. Infants are very good from the start at reaching in the dark when they cannot see their hand. This is not to say that vision is not important to the task. Infants later rely on vision to refine the path of the reach. Rather, it might be the case that learning to reach is, more than anything else, a problem of learning to control the arm. Thelen believed that infant reaching progressed by doing. Rather than infant's CNS planning the arm movement, infants adjust the tension in the arms and apply muscle energy to get the hand close to the object.
What changes in kinesthetic sensation occur during infancy?
Many infantile reflexes are stimulated through kinesthetic receptors. The first prenatal reflex that can be elicited is opposite-side neck flexion through tactile stimulation around the mouth at just 7.5 weeks after conception. At birth, infants clearly respond to touch. They can also identify the location of touches.
How might a delay in motor development affect cognitive development?
Motor development and early movement influence both social and cognitive development. For example, an infant begins to explore his environment by reaching and grasping objects; this allows for a human-object interface that involves multiple sensory systems. Such movements help create neural pathways in the brain, which are critical in the first 3 years of life. If infants are delayed in these experiences, they will miss out on some or all of these opportunities to learn to integrate sensory information.
How does manipulative skill change in older adulthood, and how can older adults adapt to these changes?
Older adults are somewhat less accurate and more variable in their performance than younger performers and the differences are greater when the moving object moves faster and when the older adults are sedentary. Older adults can improve with practice at the same rate as young adults. Repetition of skills is important in maintaining skill.
What changes in various body systems might lead to a higher frequency of falls in older adults? What might reduce the risk of falling?
Older adults experience a decline in the ability to balance. Those over 60 sway more than younger adults when standing upright. Some older adults experience changes in the kinesthetic receptors, and these changes might be more extreme in the lower limbs than in the upper ones. Older adults might also be disadvantaged due to vision changes as well as changes that occur in the vestibular receptors and nerves in adults over 75. A decrease in fast twitch muscle fibers or a loss of strength could hamper an older adult's quick response to changes in stability, as might arthritic conditions.
What are some reasons that contemporary researchers think cognitive and motor development are more intertwined than previously thought?
Perceptual motor activities provide valuable experience in performing skills based on key perceptual characteristics of a task. They can also reinforce concepts needed for motor and cognitive tasks, such as shapes and directions. A recent hypothesis posits that physical activity triggers brain activity, which facilitates learning for a time after the period of activity. - children with autism, dyslexia or language disorders frequently have motor impairments. - Functional imaging of the brain has demonstrated that the dorsolateral area in the prefrontal cortex and the neocerebellum are co-activated during performance of cognitive tasks.
Explain, from the information processing perspective and the perception action perspective, how children learn to go to the proper place to catch a ball not travelling directly toward them.
Performers were thought to receive visual and kinesthetic information and perform "calculation" on that data, much like a computer, to project the future location of the moving object in order to intercept it. The perception-action perspective, in contrast, holds that all the needed information is in the environment and that no calculations are necessary. Meaningful information in the environment specifies the action or movement possibilities of that environment and for specific events. This relationship is called affordance.
What are some visual changes that can occur with aging?
Probably the most noticeable change that occurs with vision in the aging process is the decreasing ability to see nearby images. This diminishing vision starts to become noticeable by around age 40. This is referred to as presbyopia (presbys meaning "old man" and ops meaning "eye"). The diameter of the pupil also decreases so less light reaches the retina, further reducing vision. Colour discrimination is also affected, for example, older adults may have difficulty differentiating between their blues and their greens. Lens yellow, making glare a problem for older adults. This will also affect the older adult's ability to discern contrasts and adjust from dark to light and vise versa. Other problems that might arise with aging include cataracts and glaucoma. Try this site for more information about glaucoma. Check here as well for more information about cataracts. These age-related disorders will for obvious reasons affect an older adult's ability to participate in certain activities.
What are some common visual disturbances people experience?
Problems with vision can often stem from either the shape of the cornea or the axial length (refer back to Figure 13.2).Myopia (near sightedness) is a visual problem caused when the axial length is too long. You are hyperopic or farsighted when your axial length is too short. Astigmatism occurs when there are flat areas on the cornea.
How does head control change over time?
Since human beings typically develop their movement ability in a cephalocaudal direction, the onset of voluntary postural movements begin with the head. Remember however, that even though voluntary movements have begun, during the first 6-10 months of an infant's life, these initial voluntary movements will still coexist with a number of reflexes and stereotypies. Recall that when an infant is first born, they have no voluntary control of the head or neck. Conscious or cortical control of the head makes its gradual appearance by the end of the first month. By three months, an infant can hold her head erect when being held upright in a sitting position. By five months, the infant has relatively good muscle control over her head and neck and can now raise her head from a supine position (this helps to scan the environment). At this stage, infants can now add head movement along with initial visual scans to their growing repertoire of environmental explorations.
When does walking occur?
Some infants can start to take their first independent steps as early as 8 or 9 months, most children will not walk independently until about 13 months (check p.76 in your text). It then takes until about age 4 or 5 for most children to acquire the mature walking pattern. Initial walking gait includes a wide base of support with "out-toeing". Steps are short and the landing is flat-footed with one knee locked and the other bent. There is no trunk rotation and minimal ankle movement. Arms are held high in what is called the "high guard position".
What is spacial orientation?
Spatial orientation is understanding an object's position in space. You have spatial orientation when you can recognize that two objects are the same even though one may be upside down, backwards or sideways. Spatial orientation is also the ability to recognize that a symbol's orientation may be critical to its meaning. For example, recognizing that a d is different from a b.
When balls do not come directly to the catcher, what situations (environmental and task constraints) make catching success difficult for children? For adults?
Task constraints: Size and type of ball used, throwing distance, anticipation of the ball, and trajectory of the ball. - young children are less accurate as the movement required of them gets more complex. -children's accuracy decreases if the interception point is farther away. -young children are more successful at intercepting large balls than small balls. - a high trajectory also makes interception more difficult for young children because the ball changes location in both horizontal and vertical directions. -some ball colour and background combinations influence young children's performance. E.g. kids catch balls that are in colour contrasted to the background better. - the speed of the ball affects coincidence-anticipation accuracy.
On what perceptual systems do children rely for balance, and how does this change with development?
The exact nature of the improvement trend depends on the task. For example, on some tasks we might see a plateau in performance for several years. This could reflect the way we measure improvement on that particular task, perhaps the child is improving in a way not detected by our measurement. It is also possible that children begin to rely on kinesthetic information and somewhat less on visual information for balance. Children 4-6 years have been observed to regress on moving platform tests and children 3-6 have shown both adult-like and non-adult-like postural responses to a moving room. They take longer to respond than younger children and vary greatly in the way they respond.
What is the fovea?
The fovea, found in the center at the back of the retina, is packed with cones. Cones are our photo receptors for discerning fine details and colour. This partly explains why newborns see best with contrasts, so they prefer to look at blacks and whites as opposed to more muted shades. Newborns look to the outer contours of a face for facial recognition. Most newborns can only see about 50cm. in front of them, just enough distance to see Mom's face! Interestingly enough, even a four day old baby will look longer at the contrasts seen on their mother's faces as opposed to any other face.
How does the size of an object affect the grip that an infant uses? How might this factor influence where an infant falls on Halverson's prehension sequence? How does the shape of an object affect the grip used?
The movement selected by individuals is related to their hand size compared with an object's size, or movements reflect body scaling. Object size greatly influences the grip selected, and shape has somewhat less influence. Halverson's trend that infants move from power to precision grips.
What are amodal invariants?
The perceptual systems extract patterns; many patterns are similar across the modalities. For example, events occur at a point in time, so the temporal properties of an event are not unique to any one modality. In a sense, these patterns are amodal invariants. We see a drummer strike a drum and we hear the drum's sound, but we also perceive the rhythmic pattern that existed across vision and audition.
Describe the various aspects of visual object perception.
The type of perception that allows us to find the embedded objects is figure-and-ground perception. The perception of edges and boundaries also helps us distinguish whole objects from parts of an object, called whole-and-part perception. For example, if you are driving down the street and see half a bicycle tire protruding from a row of parked cars and a child's head above it, you are not puzzled. You immediately perceive that a child on a bicycle is pulling into your path and you slow down.
Describe how humans perceive depth in the space around them.
The visual system has numerous sources of information about distance and depth perception. One source is retinal disparity. Because an individual's two eyes are in different locations, each eye sees the visual field from a slightly different angle. The information needed for judging depth comes from a comparison of the two slightly different pictures. Depth perception is aided by good visual acuity because a sharper picture from each eye provides more information for the comparison. Depth can also be assessed by moving the head through space and receiving depth cues from motion parallax. Objects in space change locations on our retinas, and nearer objects overlap more distant objects as the head moves. The transformation of optical array (optic flow), provides much information about the 3 dimensional nature of our environment. This direct means of perceiving the environment likely guides locomotion, controls posture, and helps us anticipate contact with objects and surfaces. it would seem that depth perception is in place from a very early age, but it is also a function that matures with age. Four year olds still frequently make errors in judging depth perception. By ten years of age, visual acuity is at adult levels, so by age 10, children have mature levels of depth perception.
Explain movement perception.
This is the ability to detect and track a moving object with your eyes. The medial temporal area of the visual cortex of our brain processes motion signals. Infants, even at a very young age are able to track a slowly moving object (even infants as young as three days old!) Which is why our parents all bought us movable "mobiles" to place above our cribs. Motion perception starts quite early but directional and velocity perception come later in childhood. Possibly as a survival mechanism, the edges of our retinas are sensitive only to movement. Ever notice how you spot something out of the corner of your eye?
Explain the concept of laterality.
This is the ability to distinguish between the two sides of the body. This ability is developed fairly early in most children. A child might not be able to verbalize what's left and what's right, but they are conscious of the fact that they have two hands, two feet, two eyes and that these are placed on different sides of the body. This is usually understood by age three.
What is lateral dominance?
This is the preference for the use of the right or the left hand, foot, eye or ear. When no particular dominance is seen, the person is said to be mixed dominant. Interestingly enough, whether or not you are left or right handed will have no bearing on whether you are right footed (I'm not sure if this is a word!) or if you prefer to aim using your right or left eye, or which ear you prefer to use on the phone. There is actually low correlations between preferred hand use, foot use, eye or ear use. Actually 90% of the adult human population uses their right hand for skilled activities. This is probably initially determined by heredity and later molded by subtle social and cultural pressures. Actually there is a lot of interesting literature on handedness and varying disabilities such as autism. There are a number of studies noting a preponderance of left handed individuals with autism. One such study is by Hauck and Dewey (2001) looking at hand preference and motor functioning in children with autism.
What is the role of kinesthetic development?
This is the system that tells us: - the relative position of body parts to each other - the position of the body in space - awareness of body movements - information about the objects that come into contact with the body
Describe visual sensation. How does an infants visual sensation compare to that of an adults?
This takes place when a stimulus (you see something) results in sensory nerve impulses working their way up the sensory nerve pathways to the brain. We start out with pretty lousy vision. The visual acuity (the ability to distinguish detail in objects) of a one month old infant is between 20/400 and 20/800 on the Snellen Scale. What this means is that what someone with 20/20 vision would see at, say, 400 ft.., a one month old would only be ably to see at 20 ft. In other words, a new baby only has 5% of his adult vision.
Explain directionality.
This term is often linked with laterality. A child is considered to have a sense of directionality when she doesn't have to refer to her own body to conceptualize about positions and directions in external space. This is an extension of the awareness of one's own body and the understanding of lateral awareness. For example, you need to know right and left on your own body before you can relate what's left and what's right with external objects. Recall that lateral awareness is mastered in most children by age 7, directionality is not fully developed until the age of 9 or even as late as 12. Example: Directionality is the ability to determine that a tree is to the right of a stream and to the left of the house.
What is meant by the term "motor milestones"?
Throughout that first year of life, the infant is bombarded by sights, sounds, smells, tactile and kinesthetic stimulation. A baby's big task in this first year, is to bring some order to all this sensory stimulation. Usually by the first birthday a baby generally has shown amazing progress in bringing some semblance of control to his movements. We see this gradual gaining of control of movement as a series of new motor skills that the infant acquires. These new motor skills are referred to as motor milestones.
How did views of perceptual-motor development change in the 20th century?
Today, educators and therapists are cautious about claims that participation in a perceptual-motor program can remediate learning deficiencies. Yet they realize that such participation is beneficial for children with and without learning difficulties.
When is body control present?
Usually after infants have gained some control of the head and neck muscles, they begin to gain some control over the muscles of the trunk region. This usually is seen around two months of age. At two months, an infant can now lift his head and chest up from a prone position or make postural adjustments in the trunk region when they are held upright. These early forms of postural adjustments are of course critical to that attainment of later more advanced motor skills. For example, chest elevation must occur before an infant can roll from a supine to a prone position (around 6 mos.) which will in turn allow them the positioning to initiate crawling motions.
How does vision affect balance and how do young children use vision to their advantage?
Vision tells you where your body is in relation to its surrounding environment. You also receive kinesthetic information from your body's proprioceptors that tell you where your limbs and body parts are positioned relative to each other. Your vestibular apparatus helps you adjust to your body's motion. Balance or our stability, is a state of equilibrium maintained between opposing forces. When you think about it, balance is a part of every movement task. Sometimes referred to as postural control, balance is the ability to maintain equilibrium in a gravitational field by keeping or returning the center of the body mass over its base of support. Balance is quite task specific, and to a certain degree, it depends on the form and structure of a person's body. The higher your center of mass, the less balanced you will be. That's right, women are more balanced than men! The size of your base of support will also effect balance. Balance is also developmental, consider how the size of a one year olds' head in relation to his body effects the balance of the toddler. It is believed that initially young children rely on vision primarily to maintain their balance. Researchers have studied posture and balance in infants as young as 2 months. Young infants respond with measured muscle response when placed in virtual motion conditions. Such studies have indicated that infants rely heavily on visual information for balancing. This does not necessarily change as we mature. Think about how much better you can maintain a balanced pose on one foot when you maintain a visual focus on an object.
What changes occur in the visual, kinesthetic, and auditory receptors in older adulthood?
Visual:
What is visually guided reaching?
Visually Guided Reaching (4-7 months) Babies are believed to use the position of their hand as well as observing the object to guide them in reaching. The use of vision to guide infants in their reaching for an object while at the same time, configuring their hand for the grasp is demonstrated in
How else are we able to judge our bodily position and spacial orientation?
We also are able to judge our bodily position and gain spatial orientation through our vestibular apparatus found in the inner ear . The vestibular apparatus is an intricate arrangement of semicircular canals, nerves and bones specifically designed to provide information about the position of the head in space. It is made up of: 1.) semicircular canals- provide information about 2.) rotational movements, acceleration and deceleration. utricles- picks up forward and backward movements of the head 3.) saccules- picks up sideways movements.
How do we pick up kinesthetic information and what does this include?
We pick up our kinesthetic information throughout the body via receptors referred to as proprioceptors. Somatosensors give us information about where our muscles, joints, tendons and ligaments are in space. This includes: 1.) muscle spindles 2.) golgi tendon organs 3.) joint receptors 4.) cutaneous receptors
How does kinesthetic awareness change as we develop?
We start out by not knowing too much about our bodies. Your average newborn probably can't really discern the difference between his hand and his foot. But as infants grow, they become more aware of their ability to move their arms and legs, head and trunk. Then, as the child grows, she is able to recognize verbal cues (or labels) and can identify a body part with a particular word, e.g.. "hand". The ability to label body parts is one of the first body awareness characteristics a child develops. As young as 12 months of age, infants can identify their nose, ears, eyes, hands and feet, first on their own bodies and then on others. Laterality
Explain auditory development
We start responding to sound even before we are born, but are protected at birth from very loud and high-pitched noises from a gelatinous substance that is gradually reabsorbed during the first week of life. An infant is better at hearing low-pitched tones than high pitched, but very rapidly gains near full audition by six months of age. It is assumed that hearing continues to develop into later childhood and adolescence. Hearing reaches its peak during adolescence, ironically just at the time when there is more of an inclination to listen to really LOUD music. Beyond the teen years and into our twenties and beyond, we gradually lose our auditory acuity, particularly in our ability to hear high pitched sounds.
What is size constancy?
When we see a jumbo jet airplane on the ground, we all marvel at its tremendous size. As it lifts off the ground and gains altitude, the image it makes on our retina becomes smaller and smaller, but we are still able to perceive the initial size of the airplane. Size constancy then, is the ability to recognize that objects maintain a constant size even when their image will take up more or less space on our retinas depending on their distance from the observer. This perceptual process is also referred to as constancy scaling, where your brain recognizes that increasing distances makes objects appear smaller but your brain knows the actual size.
How does maturity affect anaerobic and aerobic endurance in youth? If you wanted to predict a youth's endurance level, would you base your prediction on age, size, maturity, or some combination of these? Why?
With body growth come increases in lung volume, heart and stroke volume, total hemoglobin, and lean body mass. These factors foster improved cardiac output and improved exercise capacity and absolute maximal oxygen uptake. Average exercise capacity and body size of groups of children and adolescents increase with age, but exercise capacity is also related to maturation rate. In children, body size is a far better predictor of endurance than a child's sex. After puberty, boys on average attain a considerable edge over girls in absolute maximal oxygen uptake and have the potential to retain this throughout life.
Think about the term coincidence anticipation. Explain why someone who prefers the perception action approach might consider this to be a misnomer for interception skills.
With coincidence anticipation, it is easy to vary task characteristics and observe the effect on performance. Variations in task characteristics influence not only the product of performance, but also the process or movement pattern used in the task. For example, children who can catch small balls in their hands may choose to scoop large balls with their arms. Thus, a ttask can be defined as requiring a simpler or more complex movement response , and the characteristics of the ball can be varied to further constrain the movement. Yet many studies on coincidence anticipation are conducted in a lab setting with an apparatus that allows factors such as ball speed, trajectory, and direction to be varied and are not very similar to the real-world task of catching a ball.
How do anaerobic endurance and aerobic endurance change with growth in childhood? How do they change with aging?
Young children have smaller absolute quantities of energy reserves than adults do because they have less muscle mass. Therefore, children attain less output of absolute anaerobic power than adults do. As children grow their muscle mass increases, as do their energy reserves. They also can better tolerate the by-products of the metabolic process. Thus, mean and peak anaerobic power improve steadily as a person ages.
What is motor interference?
belief that infants cannot move voluntarily until reflexes had been inhibited by the CNS.
What is the role of muscle spindles?
found in most skeletal muscles, these pick up the degree of tension within the muscle.
What is the role of joint receptors and what do they include?
found in the joint capsule and surrounding ligaments, these include: 1.) Spray-type Ruffini endings- signal speed and direction of movement 2.) Pacinian corpuscles- respond to acceleration and very small movements 3.) Golgi-type Receptors- endings in the ligaments that signal exact joint position as well as direction
What would be the repercussions for perceptual and motor development of depriving an infant of locomotor experience?
lack of development of visual perception, affordances, surfaces, height.
What changing individual structural constraints might affect an older adult's skill in driving or piloting?
older adults have more difficulty than younger adults in dividing their attention and performing two tasks at once in driving situations. Older adults also take longer to plan movements and are slower in executing movements.
What is the role of cutaneous receptors?
these are receptors in the skin that tell us about touch, temperature, pain and pressure.
What is the role of golgi tendon organs?
these receptors are found in the muscle tendons close to the muscle junction, these signal the amount of tension in the tendon generated from muscle contraction.
What are the various aspects of kinesthetic perception, and at what age does each likely reach near-adult levels?
unlike the visual system, which relies on the eyes as sensory receptors, kinesthetic information comes from various types of receptors throughout the body called proprioceptors. Those proprioceptors located in the muscles, at the muscle-tendon junctions, in joint capsules and ligaments, and under the skin are called somatosensors; those located in the inner ear are called the vestibular apparatus. 1.) Tactile localization 2.) Perception of the body 3.) Limb movements 4.) Spacial orientation 5.) Direction