Impact of Prenatal Factors on Autism and Newborn Health
School
Barnard College**We aren't endorsed by this school
Course
PSYC BC2129
Subject
Psychology
Date
Dec 11, 2024
Pages
12
Uploaded by MinisterApe4093
Week 3 - Wednesday, 9/18/24➢Prenatal Development and the Newborn Period Cont.○Patricia Rodier (Scientific American article) → work on autism and genetic basesfor autism as they interact with teratogens■Mid-1990s, researchers began to notice link between thalidomideexposure and autism (5x higher than expected)●A chemical/drug that doctors have to women to mitigate morningsickness, which usually takes place earlier in the pregnancy●Already known that thalidomide could lead to birth defects havingto do with abnormal limbs●Rate of autism was much higher than expected for childrenexposed to thalidomide prenatally (+ malformation of the ears →structural disruption)■Scientists had already noticed subtle effect of many different types ofenvironmental risk factors■Mothers who received thalidomide very early in gestation tended to havechildren with normal limbs, malformed ears, and a higher rate of autism■Initial insult to brain stem cell formation at this particular time in fetaldevelopment had cascading effects on eye movement and facial expressionabilities●Ears are lower than normal and have a square shape■Rodier found brain stem abnormalities in a brain from a deceased autisticindividual (facial nucleus, superior olive missing; shortened overall size ofbrainstem)●Noticed that there is a part of the brain stem missing/thinner thanaverage (facial nucleus and superior olive → have to do withcontrol and processing of facial expressions + eye movement)
○Autistic individuals usually struggle with facial expressionsand eye movements■This mimicked abnormalities in a mouse which had a particular geneknocked out (Hoxa1, which is active in the brain stem when neurons areforming, but not after that)■Found human version of gene (HOXA1), whose variant does predict ahigher level of autism–but is not solely responsible■The mice with the HOXA1 gene knocked out → social andcommunication problems with other mice in their litter●Similar malformed brainstem○HOXA1 gene is associated with higher level of autism, butautism appears to bepolygenic(it is never just one genethat drives particular behavioral disorders → multiplegenetic disruptions/pre disposals + environmentalcomponents)○Some Environmental Hazards to Fetus or Newborn■Can cross the placental barrier and disrupt development of child■You may need extra prenatal care if you have any of the maternal diseases■Toxoplasmosis (parasite → can get into child and lie dormant, and expressitself later on → can go into eye and disrupt vision)●Raw steak and cat litter can carry this parasite○Teratogens■Maternal alcoholism can lead tofetal alcohol syndrome (FAS), which isassociated with mental retardation, facial deformity, and other problems■1 to 1.5% of school children show signs of FAS●FAS is considered to be on a spectrum → children exhibiting signstied to the amount of alcohol mother drank during utero○Area between nose and upper lip is very large and smooth○Disjointed eyes and button nose
■Cigarette smoking during pregnancy is linked to retarded growth and lowbirth weight●Nicotine is bad for babies●Cigarette smoking (when in utero) has also been linked toSIDS(sudden infant death syndrome), although the ultimate causes ofSIDS are still unknown○How much is driven by prenatal insult vs.current/environmental insult? Because if the mothersmoked during pregnancy, she likely still smoked after thebaby was born.○Infants tend to be smaller●Parents can reduce the risk of SIDS by not smoking, putting babiesto sleep on their backs rather than on their stomachs, using firmmattresses and no pillows as bedding for infants, and avoidingwrapping infants in lots of blankets or clothing that overheat them(for the first six months, especially)○Babies can stop breathing (breathing obstructed)○Maternal Factors■The age, nutrition, disease, and stress-level of the mother have an impacton prenatal development■Infants born to girls 15 years or younger are 3 to 4 times more likely to diebefore their first birthday than are those whose mothers are in their 20s●Ex: less likely to be taking prenatal vitamins, have accessresources, can stunt the growth of the child if mom is too small(body is not mature enough to support the baby)■An inadequate supply of specific nutrients or vitamins such as folic acidcan have dramatic consequences (e.g., growth of the fetal brain)■A variety of diseases including sexually transmitted diseases presenthazards to the fetus➢Birth○The Birth Experience■Approximately 38 weeks after conception, contractions of the uterinemuscles begin, initiating the birth of the baby●Braxton Hicks Contractions(false contractions) → your body ispreparing you to have the baby●Contractions → flood of hormones → then water will break■Research on the birth process has revealed that many aspects of the birthexperience, including squeezing in the birth canal, haveadaptive valueand increase the likelihood of survival for the newborn
●Amniotic fluid comes out of baby’s nose because baby is gettingsqueezed (clearing airways)●Kids born via c section have more birth complications becauseamniotic fluid does not come out naturally out of their noses○Head Plates■Pressure on the head during birth can cause the separate plates of the skullto overlap, resulting in a temporarily misshapen head (a “soft spot”)●To allow for brain growth and more easy/ready birthing●Brain can grow during infancy and then come to fuse■Fortunately, the condition rapidly corrects itself after birth➢The Newborn Infant○Case Study: The Beng (The Beng and newborns)■Believe that newborns are reincarnations of ancestors■The ‘wru’ (spirit) is not fully committed to earthly life until after theumbilical cord has fallen off newborn■At this point newborn is considered to be a person- no funeral if child diesbefore this■Elaborate happiness rituals, hastening of stump removal○Interacting with the Environment■State: The infant’s level of arousal and engagement in theenvironment(ex: sleeping states, crying states, etc.)●Ranges from deep sleep to intense activity●Is an important influence in the newborn’s exploration of the world○The Six States of Arousal■Active sleep■Quiet sleep■Crying■Active awake■Alert awake■Drowsing●Coming in and out of consciousness
■Newborns spend a lot of time sleeping (⅔ of their time sleeping) for thefirst few weeks■Cry for an average of 2 hours a day●With time, parents get better at distinguishing cries (ex: hunger vs.pain cry) + infants get better at communicating with time○Sleep■Newborns sleep twice as much as young adults■The pattern of two different sleep states changes dramatically●REM (rapid eye movement) sleep: an active sleep stateassociated with dreaming in adults and is characterized by quick,jerky eye movements under closed lids●Non-REM sleep: A quiet or deep sleep state characterized by theabsence of motor activity or eye movements and by regular, slowbrain waves, breathing, and heart rate■REM sleep constitutes fully 50% of a newborn’s total sleep time (there areno other populations that sleep this much) and declines rapidly to only20% by 3 or 4 years of age■According toautostimulation theory,brain activity during REM sleep inthe fetus and newborn makes up for natural deprivation of external stimuliand facilitates the early development of the visual system●“Our brains are stimulating themselves if they do not get enoughinput” → newborn brain makes up for lack of stimulation duringtheir waking hours
●Older people do not sleep as much■The mystery of sleep●Why sleep?○To avoid nighttime predators■Adaptive when we were evolving (we needed to laylow so we were eaten)●Not the best explanation because to avoid athreat, it is better to be conscious○To reduce energy demand○To restore our bodies■Provides body with dedicated block of time torestore itself, specifically the immune system andother “cleaner” systems (clearing debris, dead cells,etc. from blood stream)●Immune system programming (ex:post-vaccination) has evolved to take placewhile we are asleep○To reorganize our brain structure○Sleep, learning, and memory■Infants have a great deal more REM sleep●Dreaming → creating novel experiences from things that haveoccurred to us (also imagining)●REM sets the stage for information to be processed●When something unresolved happens in your day, we tend todream about that particular thing
○Ex: With rats, if you give them a maze, the same areas ofthe brain that are active while they run the maze are activewhile they dream (REM sleep)■They also have more slow-wave sleep, and this higher percentage ofslow-wave-sleep persists until adolescence■Consolidation occurs in slow-wave sleep (the reactivation happens duringREM sleep)●Moving info from short term/working memory to long termmemory → a more permanent store■REM is stimulate, Non-REM is process■90 minute intervals■Slow wave sleep takes info from our day/dreams and it consolidates it■Early in the evening, we experience more slow wave sleep and later in theevening, we experience REM sleep●If you wake up naturally, you are more likely to remember youdreams vs. if you wake up via an alarm○Hupbach et al. (2009)■15-month-old infants■Given an artificial language sequence to learn, either within a “nappingwindow” (<4 hours from learning, Exp 1) not within this window (Exp 2)●Gave them a sequence of syllables that had a particular relationshipthey needed to learn■This artificial language capitalized onstatistical learning, discovered inlate 90s
●Says, “we are able to keep track of all of the subunits of theenvironment and how frequently they co occur with each other”■Tested whether they recalled the “word” that was taught, or an abstractionof that word, or unfamiliar dependencies■The children listened to an artificial language requiring them to tracksequential dependencies between the first and the third words inthree-word sentences (e.g. pel - wadim-jic, vot - kicey-rud, pel-deecha-jic). The middle element in the strings came from a large set ofwords●These syllables are co-occurring with a 100% probability■Ex: “Tokibu” is a word that hangs together because of itsstatisticalco-occurrence■Required the infant to learnt hat every time you learn the first syllable ofthe word, it was going to be followed by the third syllable of the word(non-adjacent learning)■Infants listened longer to test items where the first “word” and third“Word” were consistently linked to each other (e.g., co-occurred). Theygot the abstract principle–but only if they could nap within 4 hours ofhearing it●Infants all got tested 4 hours later, but some of them had taken anap while others did not (opportunity to process/consolidateinformation → slow wave sleep)
○Memory (and its subsystems)■Iconic memory(quick, perceptual, like a screenshot before it gets deleted)—>short term memory(if you are paying attention to information fromiconic memory) —>long term memory(traceable, recallable memory)■Declarative(semantic) memory (ex: verbal, facts) as separable fromnon-declarative(procedural) memory (ex: automatic, implicit, motoric →ex: riding a bike, driving which goes from explicit/effortful toimplicit/automatic)○Seehagen et al. (2014)■Can sleep help with consolidation of declarative memory?●Events that happen related to meaning in the environment■How to measure declarative memory in infancy:deferred imitationprocedure■Tested infants after a 4-hour window (Exp 1) and a 24-hour window (Exp2)■In order to make sure the kids were napping or not napping, theymonitored their activity via an ankle monitor (to ensure uninterruptedsleep)●Group that had a nap between exposure and recall●Group with no nap between exposure and recall●Control groups that did not have exposure○Did not see demonstration of adult taking mitten off stuffies■Kids were given stuffies, adults demonstrated specific actions (ex: takingmittens off stuffies)●After the time windows, did the kids remember they could do thesespecific activities with the stuffies?
■Infants who had a nap performed significantly more of the target actionsrelative to baseline infants and those who did not have a nap●Napping → consolidating info into long term memory →importance of sleep○Crying■Early in infancy, crying reflects discomfort or frustration■Crying gradually becomes more of a communicative act■With experience, parents become better at interpreting the characteristicsof the cry itself●Whine vs. sharp yell
■Many effective soothing techniques, including swaddling (wrapping ababy tightly in cloths or a blanket), involve moderately intense andcontinuous or repetitive stimulation●Karp’s 5 S's–swaddling(put thin blanket on back of baby, foldtop and tuck underneath back of baby, bring up bottom part andbend baby’s legs, bring the top over and tuck it behind baby),sideposition(take swaddled baby, do “the football hold,” support headand ears, support butt with other hand/or with hips, move tight toyou),shushing(verbally “sssshhh”),swinging(do while shushingloudly, giving baby a bit of a jiggle and a swing; intensity willsimulate the womb),sucking(take a clean pinkie and have babysuck on it) → put baby in crib, lay them down while you are stilljiggling and shushing, back away slowly – make the baby feel likethey are in the 4th trimester (in the womb again)○Recreate the environment in the womb (ex: noise,movement, jostling, pressure, etc.)■Parents of babies withcolic, (excessive crying for no apparent reason)should seek social support and relief from frustration—and remember thatcolic typically ends within a few months○Infant Mortality■Death during the first year after birth (infant mortality) has become arelatively rare event in the Western industrialized world●However, rates in the United States are the 31st highest in theworld…●African-American infants are more than twice as likely to diebefore their first birthday as Euro-American babies○Racial and ethnic disparity●Poverty and lack of health insurance are associated with high ratesof infant mortality○Resources mothers of color have access to is a factor ininfant mortality○Doctors/medical professionals not taking pain of mothersof color seriously (mistreatment)○Low Birth Weight Infants■Infants weighing less than 5.5 pounds (2,500 grams) are considered to beoflow birth weight (LBW)●LBW infants born at or before 35 weeks after conception aredescribed aspremature
●Other LBW infants are referred to assmall for gestation age(SGA)when their birth weight is substantially less than the normfor their gestational age○Ex: You can be 5 pounds at 36 weeks and you would beconsidered SGA because at 36 weeks, you should be largerthan that○Risk Factors■Tend to occur together in the world■A negative outcome is more likely when there are multiple risk factors●Ex: Teratogens●These things cluster; they are not additive; they are non-linearlyrelated to each other●The clustering drives the negative outcome○Ex: Dropping out of school■The more risk factors you have, the more likely youare to drop out of school whereas the fewer youhave, the less likely you are to do so■Despite multiple risk factors, however, some individuals do well(resilience)