Test 2 Chapter 5 10 Changes in Body proportions Cephalocaudal than the lower part of the body from the latin for head to tail During prenatal period the head develops more rapidly at birth head takes up one fourth of total body length and legs are only one third at age 2 head takes up one fifth and the legs are one half of the body length proximodistal trends proximodistal Prenatal growth period proceeds literally from near to far from center of the body outward period head chest and trunk grow first then arms and legs then finally hands and feet infancy and childhood arms and legs continue to grow somewhat ahead of hands and feet height and weight average baby is 20 inches and 7 5 lbs when they are born Most babies will lose 5 of their weight in the first few days Double their weight by 5 months triple at 12 months quadruple by 2 years Grow about 1 inch a month the first year and grows slow in the 2nd year Cultural differences in physical development Brain development in infancy toddlerhood at birth brain is nearest to adult size than any other physical structure about 25 of adult weight there is major brain growth in the 1st year early experience important to brain growth babies in deprived environments have different brain growth than babies in enriched environment can look at it in a microscopic level with individual cells or at the whole cerebral cortex development of neurons neurons synapse neurotransmitter neurons are produced in embryos primitive neural tube during infancy and toddlerbood neural fibers and synapses will increase neurons die 20 to 80 percent die depending on the brain region synaptic pruning neurons that are seldom soon lose their synapses returning neurons not needed to an uncommitted state so they can support future development 40 of synapses are pruned require stimulation reason for brain size Sensitive periods adopted Glial cells which are responsible for myelination continue to increase and multiply from preganancy to 2 years of life 30 of adult weight to 70 Those in orphanages had lower brain function and higher stress than those who were soon after birth Appropriate stimulation and sensitive adult care will help with cortisol production Brain plasticity a highly plastic cerebral cortex in which many areas are not yet committed to specific functions has a high capactity for learning If part of the cerebral cortex is damaged other parts can take over the tasks Brain is more plastic in the first few years contains an overabundance in synaptic connections which support brain plasticity and lead to it being easier for children to learn Experience will cause hemisphers organization Left sequential analytic processing piece by piece language and communication speech sounds Right holisitic integrative manner spatial information and regulating negative information non speech sounds Experience expectant refers to the young brains rapidly developing organization which depends on ordinary experiences Oppurtunities to see and touch objects to hear language and other sounds and to move about and explore the environment Occurs early and naturally as caregivers offer babies go off a daily schedule and sets their foundation for the experience dependent Experience dependent result of occurs throughout our lives it consists of additional growth and the refinement of established brain structures as a specific learning experiences that vary widely across the individual cultures examples reading and writing and playing games Breastfeeding benefits Infants needs are atleast twice those of an adult 1 provides the correct balance of fat and protein human milk is higher in fat and lower in protein ideal for rapidly myelinating nervous system 2 ensures nutritional completeness iron is breast milk is easier absorbed doesn t need to add food until 6 months 3 helps ensure healthy physical growth 1 year old breastfed have a higher percent of muscle to fat 4 protects against many diseases transfers antibodies and other infection fighting agents anti inflammatory effects first four months will lower blood cholesterol and cardio vascular disease 5 protects agains fualty jaw development and tooth decay suckling will form top and bottom jaw 6 ensures digestibility different kind of bacteria growing in their intestines 7 smooths the transiton to solid foods experience with a variety of flavors that pass through the mothers diet Growth faltering Operant conditioning Emotional well being a term applied to infants whose weight height and head circumference are substantially below age related growth norms and who are withdrawn and apathetic Dirsturbed parent infant relationship contributes to this failrure to grow normally Infancts act or operate on the enviromnet and stimuli that follow their behavior change the probabilyt of the behavior will occur again Reinforcer will increase the occurrence of a response Punishment removing a desirable stimulus or presenting an un pleasant on to decrease the occurrence of a response memory and social relationships habituation stimulation recovery tretun refers toa gradual reduction in the strength of a response due to trepetitive looking heart rate and respiration would decrease a new stimulas a change in the environment would cause a responsiveness to to a high level and increase this will asses a babies recent memory Dynamic systems theory of motor development Mastery of motor skills involves acquiring increasingly complex systems of action When motor skills work as a system separate abilities blend together each cooperating with others to produce more effect ways of exploring and ctonrolling the environment Example learning to walk takes practice of 6 or more hours a day Motor development cannot be genetically determined more by exploration and desire to master new tasks Bowel and bladder control Best delayed until months following the second birthday Bothered by wetness shows readiness Starting before 27 months will prolong process while waiting til 3 years 4 months of training Toilet routine praise and gentle encouragement Piaget s theory sensorimotor stage Spans the first 2 years of life Believed that infants and toddlers think with their eyes ears hands and other sensorimotror equipment 1 reflexive scheme birth to 1 month and is new born reflexes 2 primary circular reactions 3 4 1 4 months involves stumbling onto a new experience caused by the babys own motor activity As infant tries to repeat the event again and again a sensorimotor