Chapter 5 Infants double their birth weight by the fourth month and triple it by age 1 In birth catch up small babies experience extra gain of fat which is stored to keep the brain nourished if teething and sniffles interfere with sucking A phenomenon called head sparing is if nutrition is temporarily inadequate the body stops growing but not the brain An infant s percentile is a number that indicates rank compared to other similar people of the same age and it allows a given child to be compared to other children Newborns spend most of their time sleeping about 15 to 17 hours a day but hours of sleep decrease rapidly with maturity It matters not what infants sleep on but the position is important always on the back Responsive parents full term newborns that are well fed sleep more than low birth weight newborns If parents respond to predawn cries with food and play babies learn to wake up early night after night Regular and ample sleep correlates with normal brain maturation learning emotional regulation academic success and psychological adjustment REM sleep rapid eye movement flickering eyes and rapid brain waves that indicate dreaming Co sleeping is when the parents sleep beside their infants Central Nervous System CNS is the brain and the spinal cord and it begins with the nerve cells called neurons Most neurons are in the cortex the brain s six outer layers where most thinking feeling and sensing occur The brainstem controls automatic responses heartbeat breathing temperature and arousal The prefrontal cortex is the area for anticipation planning and impulse control Neurons are connected to other neurons by nerve fibers called axons and dendrites the axon of one neuron meets the dendrites of another at intersections called synapses communication links Transient exuberance is the early dendrite growth by fivefold during the first 2 years after birth and followed by pruning where unused connections will die The loss of dendrites increases brainpower because it allows more pruning and fosters complex thinking The process of extending and eliminating dendrites is attuned to experience as the appropriate links in the brain are established protected and strengthened Experience expectant brain function is when certain functions require basic experiences in order to develop brains expect these experiences and development would suffer without them Experience dependent brain function is when functions depend on particular experiences which are not essential allowing humans to be quite different from each other Infants need stimulation Varied sensations and movement help with better brain connections Lack of stimulation is harmful because the brain may overproduce stress hormones which can damage the brain s later functioning Shaken baby syndrome is a life threatening condition that occurs when infants are shaken back and forth It stops crying because blood vessels in the brain rupture and neural connections break The language areas of the brain develop most rapidly between the ages of 6 and 24 months the time where infants need to hear speech in order to talk fluently Self righting is the inborn drive to remedy deficits their brains expect human interaction and whatever objects their parents find that interest them Myelin is the insulation that forms on the long outgoing fibers of neurons and prevents neighboring cells from short circuiting each other s activity speeds up transmission of signals but the process of myelination is not completed until the age of 3 Sensation is when a sensory system detects a stimulus beginning with an outer organ 5 senses Perception occurs when the brain notices and processes a sensation requires experience Infants brains are attuned to repeated social experiences such as a repeated name of an infant Sensation Perception Cognition when people think about what they perceived Infants acute sense of hearing and maturing brain helps distinguish patterns of sounds and syllables Vision is the least mature sense at birth and improves to see shapes and notice details by 3 months their visual scanning becomes organized and more efficient Binocular vision is the ability to coordinate the two eyes to see one image Sense of smell and taste function at birth and appreciate whatever their mothers eat and taste preferences endure when a person migrates to another culture and learn to recognize each person s scent preferring to sleep next to their caregivers Sense of touch is acute in infants and things that are painful to adults are less painful to newborns These sensations help social interaction response to caregivers and comfort soothed amid the disturbances of infant life and the most important experiences are perceived with the senses Genetics cultural patterns and nutrition all affect the individual differences among infants Affordances are the opportunities that infants see when they focus on something and depend on sensory awareness immediate motivation current development and past experience Infants and toddlers depend on their caregivers to interact with them with a split second precision called synchrony and they later on create an attachment Stranger wariness is when an infant no longer smiles at any friendly face and cries if an unfamiliar person moves too close too quickly Separation anxiety is expressed in tears dismay anger when a familiar caregiver leaves Immunization primes the body s immune system to resist a specific contagious disease but no immunization were found for AIDS malaria cholera typhoid and shigellosis Colostrum is a thick high calorie fluid secreted by the mother s breasts at birth and those babies that are breast fed are less often sick Protein calorie malnutrition occurs when a person does not consume sufficient food to sustain normal growth and causes stunting being very short for their age because chronic malnutrition kept them from growing Wasting is when children are severely underweight for their age and height Marasmus is when growth stops body tissues waste away and an infant victim dies and kwashiorkor is when growth slows down the liver is damaged the immune system is weakened energy is reduced hair becomes thin brittle and colorless