How Environmental Influences Impact Infant Intelligence

Environmental Effects on Infant Intelligence

Infant cognitive development has fascinated scholars for decades. Phyllis L.F. Rippeyoung says that Jean Piaget, a well-known psychologist, suggested that cognitive skills originate at birth, arriving in stages in which the child gains more knowledge and skill. Through this, the child learns about the world (“Is It Too Late …” 242). The environment of an infant hugely affects its cognitive abilities, and the identification of environmental factors can help to reduce the risk and symptoms of disabilities. Children can be very intelligent, and the environmental influences that surround the child can determine his or her future, depending if the influence was positive or negative. Even one seemingly unimportant factor from the environment can dictate how cognition develops. Environmental effects can be many things, such as chemical and drug-related factors, family interaction and stimulation, the parents’ mental statuses and marital status, infant nutrition and health, and race.

Scholars Stephen A. Rauch and Bruce P. Lanphear wrote an article about how environment relates to disabilities in children. They studied how identification of and control of the environment is relevant to the prevention of disabilities (193). Environment plays a significant role in the determination of whether a child develops symptoms of a disability. It is vital to know how the environment changes cognitive functioning in infants, specifically because many disabilities are on the rise. These include asthma, premature birth, autism, ADHD, and obesity (197).

Today, the prevalence of autism is rising. It is one of the most debilitating diseases, starting in childhood (Rauch and Lanphear 200). While researchers do not know much about this condition, they have discovered that one of its causes could be environmental; researchers introduced this theory because of the sudden rise of autism (Rauch and Lanphear 201). Suspected environmental risks are mercury, lead, tobacco, organophosphate pesticides, polychlorinated biphenyls, manufactured chemicals, and mixtures of many chemicals (Rauch and Lanphear 201).

ADHD is also becoming more common in children; it affects roughly one in every ten children (Rauch and Lanphear 201).The suspects of its environmental causes are similar to those of autism. Rauch and Lanphear announce, “While the use of biomarkers has allowed scientists to connect environmental exposures to disabilities in children, the long latency between exposure and disability makes it difficult to establish these links with certainty” (201). They then comment on what is being done about these serious issues: “Still, these studies raise serious questions about the need to revise the existing regulatory framework—which essentially allows children to be exposed to suspected toxicants or chemicals until there is definitive proof of their toxicity” (201). These risks are very problematic, and it is dangerous not to notice their effects at the last minute, when children are already beginning to develop the disorders.

According to Rauch and Lanphear, three possible methods for the prevention of disabilities exist: education, enforcement, and engineering. The education involves teaching people about the disabilities and the factors that increase the risk. Enforcement utilizes laws that protect against ill behavior. Lastly, engineering requires careful handling of the environment to reduce exposure as much as possible (203).

Most environmental factors have to do with the physical environment that the children are in—their homes and neighborhoods. In poverty-stricken towns and villages, the unsanitary atmosphere, toxic waste, and other types of pollution all can cause symptoms of disabilities (Rauch and Lanphear 195 and 198). Some homes expose infants to lead paint, and this is associated with cognitive problems such as low IQ and ADHD (Rauch and Lanphear 197).

Several other factors can influence the cognition of infants. Rauch and Lanphear state, “…environmentally induced conditions incurred during childhood can compound throughout a person’s lifetime and express themselves as chronic diseases in adulthood or old age” (197). This encompasses many kinds of disabilities, but includes cognitive limitations as well. Rauch and Lanphear have learned that many researchers are looking into the effects of toxins on cognition. They say, “Black carbon has been associated with lower verbal and nonverbal intelligence and poorer memory performance...” More and more studies are finding this to be a common discovery. Rauch and Lanphear continue, “These links between airborne toxins and cognitive performance are less established, but they fit a larger pattern of toxic exposures interfering with brain development in young children” (200). Even at the smallest level of exposure, the toxins can be dangerous; it is harmful to the unborn and infants (Rauch and Lanphear 200). If the mothers happen to face these toxins and chemicals, they are at risk for delivering prematurely, which in turn could affect the cognition of the child. Scholars are realizing that not only mothers are at risk. All people are at risk for exposure; no one is safe (Rauch and Lanphear 200).

Drugs and chemicals can have a very negative effect on any human, but especially infants because of their age and underdevelopment. Infants are more susceptible to the negative influences of drugs than adults. In fact, Ian Adatia and others agree with Rauch and Lanphear that the negative influences of drugs may cause temporary or life-long damage to the brain (253). Many kinds of drugs and chemicals, including cocaine, alcohol, nicotine, and marijuana, can not only damage the brain, but also stunt the growth of infants. This is why doctors advise mothers not to engage in drug use or activities during the gestation period. Authors Rina D. Eiden, Yvette Veira, and Douglas A. Granger say, “Studies have shown that chronically elevated levels of cortisol can have deleterious effects on the brain, including deficits in memory, learning, state-regulating capacities, and socioemotional development” (528). Even after the child is born, the exposure to these things can create risks to the child’s physical, mental, and emotional health. Infants may experience higher levels of stress, higher reactivity to cortisol, slower recovery time, and poor parenting (Eiden, Veira, and Granger 529). The parents are large sources of influence in an infant’s life. If mothers use any type of drug, this will change their reactions to needs of the children. In studies, they have shown to be less sensitive and less responsive while interacting with their infants (Eiden, Veira, and Granger 529).

Family interaction is perhaps the most noticeable environmental agent that influences the cognition of infants. Scholars Natasha J. Cabrera and others discuss the particular influences of parental interaction and relationships. They studied a sample of Latino infants with their parents to come to conclusions about infant cognition. Their experiment consisted of trained field staff visiting homes to view the interactions. They performed a computer-assisted interview with the mothers, took videos of the interactions between mother and child, and assessed the cognitive development of the infants (Cabrera et al. 1194). The videos that the field staff took ranged from forty-five seconds up to five and a half minutes, focusing on the mother teaching the infant a small task, such as hitting blocks together or turning pages of a book (Cabrera et al.1194). The field staff gave the father of the child a questionnaire to complete based upon his relationship with the child. They did not focus quite as much on the father’s interactions.

The authors concluded that both the mental statuses and marital status of the parents directly affects the infant. Parental depression is “associated with more marital problems and higher levels of maternal and paternal hostile or negative parenting such as insensitivity to infants’ cues and inadequate stimulation” (Cabrera et al. 1191-1192). One proof of this is in the results of the experiments of Cabrera and others. They examined the interactions between mother and child, with the results shown on infant cognitive testing scores. They discovered that if the mental status of the mother was healthy and positive, the child’s test score was much higher (Cabrera et al. 1201). If the mental status was more depressed, the infant’s test scores were much lower (Cabrera et al. 1203).

If the mental health of each parent is not doing well, the parents’ marriage may not do well. Eventually this will affect each parent’s relationship with the infant. This is why both a good mental and good marital status is important; both have a very significant influence in a baby’s cognitive development. A failing or unhealthy marriage relationship between the mother and father negatively affects the offspring and vice-versa. The authors write, “…positive mother-father relationships in European American and Mexican-American families have a direct positive effect on child adjustment, whereas marital conflict predicts child maladjustment” (1192). In other words, if the parents’ marriage is doing well, the child will reciprocate good feelings. This correlation is present not just with babies, but with older children, adolescents, and young adults, especially if the relationship between the parents and offspring is close.

Researcher Rippeyoung gives a similar factor that relates to infant cognition—the family structure (“Is It Too Late …” 240). A mother faces much more pressure if she has never married or separates from the child’s father. In this situation, the infant’s cognitive abilities may be limited more than they would be in the opposite situation (240). It is better for the baby’s mother to be married. Stress levels decrease, both in the mother and in the child. Negative effects on the infant’s cognitive functioning are fewer.

The parents’ individual relationships with the baby are important; this includes stimulation of the child. Researchers Joscha Kärtner, Heidi Keller, and Relindis D. Yovsi analyzed some mothers’ interactions with their babies. They say that usually, “Mothers intuitively react to infants’ signals within a short period of time, normally less than a second” (540). In all families, this looks different. Nulliparous mothers usually worry about their child more than multiparous mothers. Whether the mothers know it or not, this type of behavior assists their infants’ growth. Stimulation is necessary for babies’ brains to develop. When the mothers react, the infants start to “perceive themselves as causal agents whose behavior directly affects their social environment” (Kärtner et al. 540). Kärtner, Keller, and Yovsi then state, “This knowledge has fundamental implications for infants’ subsequent cognitive and socioemotional developmental processes” (540).

Rippeyoung says that there have been scholars who dispute the negative consequences on cognition because of a larger amount of siblings (“Is It Too Late …” 240). The more children in a family, the more quickly spread and depleted they become. Though this is true, the scholars are not positive that it specifically negates the growth of infant cognition (240).

Rippeyoung argues that infant stimulation is the key to cognitive growth. This is how infants learn language (“Is It Too Late …” 239). Stimulation should come heavily from the parents, but also important is the stimulation from non-family members. Stimulating interactions can include but is not limited to reading, singing, telling stories, playing peek-a-boo, and tickling (239). Rippeyoung then mentions the concept of “direct talking” which refers to using language in such ways as repetition, imitation, questioning, and reading (239).

Parental interaction with the baby stimulates the child’s growth. Where there is no stimulation, there is no cognitive growth. As Rippeyoung says, stimulation is extremely important because without it, a child cannot learn language, and without language, the child cannot communicate to its parents, nor to the rest of the world (“Is It Too Late …” 239). Stimulation challenges them not only to learn to communicate, but also to use their senses in order to learn about the big world surrounding them (239). Rippeyoung suggests that the error of mothers not stimulating their infants stems from the mother’s decision to head back into the work force (239). She does not get nearly enough time with the infant because she is gone most of the time. Although non-family members, such as babysitters and day care providers, can stimulate the child with interaction, the specific stimulation by mothers is unique and incomparable.

Stimulation is very beneficial for infants, but sometimes can have a negative effect on children. The mental status of the parents or caretakers determines the kind of stimulation the child receives (whether it is good or bad). Researchers Liat Tikotzky and Avi Sadeh have examined the role of parental cognitions in infant sleep, and have suggested, “Parental cognitions regarding child behavior have been associated with child behavior. It is assumed that the influence parental cognitions have on child behavior is mediated thought the way parents behave and react to the child” (861). When an infant wakes during the night, the parents may become irritated because they are exhausted from all the stress parenting involves. Therefore, as the parents try to soothe and settle the infant back into sleeping, their mindset toward the infant could be inapposite, giving the child negative or concerned feelings. The parents could also be disengaged from the task on hand (861). Tikotzky and Sadeh declare, “… infant sleep problems [are] significantly correlated with maternal cognition related to difficulty with limit setting, increased doubts regarding parenting competence, and increased anger at the infant’s demands” (861). An unhealthy attitude from the parent negatively affects the child. This kind of stimulation does not benefit infants.

Along with stimulation, the health of an infant also greatly influences his cognitive abilities. It is clear that malnourishment decreases cognitive functioning. Breastfeeding is one part of a baby’s environment that may considerably influence the child’s future. The benefits of breastfeeding are a largely debated topic among researchers; some say that it provides sufficient nutrition while others negate that. New research suggests that breastfeeding positively influences infant cognition, though the extent of this is not completely certain. Seaneen Sloan, Moira Stewart, and Laura Dunne state, “Cognitive development is known to be dependent on a wide variety of genetic, environmental, and socio-economic factors” (107). The authors conclude that the results are “unclear whether differences in cognitive performance reflect a direct nutritional advantage of breast milk” (Sloan, Stewart, and Dunne 107). Although this is true, there definitely can be some positive sides to breastfeeding, but this research communicates that the positive results might not show up unless coupled with other factors, such as a certain length of time for breastfeeding and good parenting behaviors (Sloan, Stewart, and Dunne 108).

Rippeyoung has also studied the effects of breastmilk on infants and young children. She says that breastfeeding provides some explanation for the deficiencies in the cognitive development of infants (“Can Breastfeeding Solve Inequality? The Relative Mediating Impact of Breastfeeding and Home Environment on Poverty Gaps in Canadian Child Cognitive Skills” 66). She states, “Research has consistently demonstrated a positive effect of breastfeeding on child health outcomes, as evidenced by its promotion by Health Canada, the Public Health Agency of Canada, and the World Health Organization” (69). She then argues that breastfeeding helps children to achieve higher IQ scores (69). Scholars have many differing opinions on this topic. Some say that the milk itself does not determine the IQ of the child, but the genetics of the mother do. Both sides of this argument have very good reasoning. Researchers have conducted many studies, but many of them do not account for the mother’s IQ. Sloan’s study also did not account for the mother’s IQ, but it did take into account the mother’s education levels.

A highly reputable study factors in the mother’s IQ. The results of this study show that breastfeeding the infants was not the major cause of high IQ, but rather the cause was the heredity of the mother’s high IQ.

Racial differentiation is one more factor that has something to do with the cognitions of infants. Since at least 1917, the testing scores of black people have been consistently and significantly lower than the scores of white people. Rippeyoung looked at the differentiation and its beginning, in infancy. She used the Early Childhood Longitudinal Birth Cohort (ECLS-B) data to “assess whether there is a racial gap in cognitive skills, measured by such things as child’s exploration, babbling, early problem solving, and use of words, among infants between the ages of six and twenty-two months… and what factors explain it” (“Is It Too Late …” 236). The cause of the gap in its entirely is extremely complex, with many factors adding to it, but Rippeyoung examined some of them.

Previous researching from scholars past has determined that family background and socioeconomic status, to an extent, have created the gap between the testing scores of black children and white children (237). Rippeyoung says that sometimes, economic inequality is the cause of the gap, but also says that this cause does not completely determine the gap (237). Another possible cause for the gap is the lack of stimulation in infants because of the mother’s employment behavior (239). This is especially true for poorer families, but not necessarily families of differing race, who need the extra income, forcing the mother to find work. Rippeyoung has found from other scholars that “the mother’s employment seems to have a negative effect on non-Hispanic white children but not on children of other races” (239). She continues to announce, “Thus, it may be that for poorer, African American families, working provides a boost to family resources but that among those with adequate resources, working may reduce the amount of cognitively stimulating interactions in which parents can engage” (239).

Roland G. Fryer and Steven D. Levitt have also done some researching and found this gap; they have learned that it is primarily among people older than two years old. With a look at the data from the ECLS-B, they found just a minute amount of disparity between the test scores of black infants and white infants, aged eight to twelve months old. In terms of standard deviation units, the difference is at a level of about 0.055. They also say that the scores of Asian and Hispanic infants are slightly lower than that of whites. Though there are these small differences in the cognition of infants from different races, there are not any significant differences until the infants grow to be two years old. The difference in standard deviation units at this level becomes about 0.3 to 0.4, a much greater disparity. This difference continues to widen as the children age further, just as Rippeyoung concluded (981-982).

The environment has a large role in the cognitive development process of infants. Chemical and drug-related factors, family interaction and stimulation, the parents’ mental statuses and marital status, infant nutrition and health, and race all may influence cognitive development. By understanding the environmental factors that influence infants’ cognition, scholars can gain knowledge of how possibly to prevent disabilities from becoming a determinant of an unfortunate future for the child. Today, autism and ADHD are on the rise. It is a shame to think that researchers and scholars could have prevented them if only they identified the possible environmental causes.