The Effects of the Environment on Child Development

The Effects of the Environment on Child Development Ms. Carmelitano

Effect of the environment on cognitive development • Paul Krugman (economist) 2008 Wrote a piece in the NY Times discussing findings of neuroscientists Children growing up in poor families experience high levels of stress hormones that may impact brain development and cognitive functions He argued that children born in poor families have a 50% chance of remaining poor 1/3 of children from low-income communities are behind their peers By 4 th grade 50% do not meet reading standards (National Center for Children in Poverty 2002)

Poverty and Development • Research has shown poverty is a major risk factor in a child’s cognitive development • Poor nutrition, poverty-related health problems, home environment, parenting practices, and unemployment are all factors which may impact cognitive development AND the possibility of the influence of education

Risk Factors vs Protective Factors • Risk Factor Any variable that increase and individuals probability of developing certain traits In this unit the trait is poor cognitive development Include: Stress over meeting basic needs of food, shelter, safety Malnutrition Substance abuse in the community Maternal depression Exposure to environmental toxins Trauma caused by insecurity in the community or lack of safety Abuse Discrimination Less stimulation in environment

Farah et al (2005) • Found that low SES children (children from families in a lower socioeconomic status household) performed worse on all test of cognitive performance when compared to middle SES children Farah et al (2008) found that there was a positive correlation in 110 African American middle-school children (evaluated at age 4 and 8) between environmental stimulation and language development. There was also a correlation between parental nurturing and long-term memory performance. • WHY? Old Theory: The Main Effect Model: Argued that poor nutrition in the first two years of life halts the normal development of the brain and leads to permanent damage and cognitive impairment High levels of stress during important brain development can lead to higher levels of glucocorticoids in the brain, causing cognitive impairment Lack of stimulation in the environment can inhibit dendrite formation and growth New Theory: Malnutrition may hinder cognitive development (theory of delated cognitive development)

Fernald and Gunnar (2008) • Aim: Shows how poverty affects children's mental health by altering their cortisol levels. • Procedure: Surveyed 639 Mexican mothers and their children. Took blood samples from their children Found that children of depressed mothers living in extreme poverty produced less cortisol. The low levels of cortisol indicated the stress system was worn out, leaving children susceptible to depression. • Remember: Cortisol is released in times of stressed If you are over-stressed, your body may stop producing cortisol Low cortisol levels may be linked to depression (Although so are high levels)

Meany et al (1998) • Carried out a study of the role of stress hormones (Glucocorticoids) on memory • Procedure: Animal study Randomly assigned rats to one of two groups: Treatment group: Newborn rats were handled daily by researchers for three weeks. During this time they were taken from their mothers for 15 minutes and placed in a plastic container lined with a paper towel. They were brushed for 15 minutes to stimulate grooming of the mother Control Group: Infant rats were taken from their mothers and placed in a container but not handled To test the effect of this early stress, at two-years old, the rats were put into a pool of milky water. In it was a platform which the research team could use to track the route the rats used to get out of the water, based on their memories of previous escapes

Results • The researchers found that high levels of glucocorticoids - stress hormones - in the early life of a rat resulted in changes that affected the rats in old age. Increased exposure to adrenal glucocorticoids accelerated hippocampal neuron loss and cognitive impairments in aging. The rats taken away from their mothers at a young age and were not groomed by the researchers took a much more convoluted route to get to the platform when they reached old age. • Hippocampal cell loss and pronounced spatial memory deficits emerged with age in the neglected rats, but were almost absent in the rats groomed by the researchers. It appears that the extra stroking that the rats received led to an activation of genes which are responsible for the reaction to the stress response. The grooming process “turns on” the genes which help the young rat cope with stress - which then leads to a longer and healthier life. • Long term exposure to cortisol causes neurons to admit more calcium through channels in their membrane. • This leads to over-stimulation which then leads to hippocampal cell death. This is a problem when it comes to our ability to create memory as the hippocampus is the location of acetylcholine receptor sites. • Loss of hippocampal cells correlates with lower levels of acetylcholine. Research shows that there is a correlation between high levels of glucocorticoids, low levels of acetylcholine and Alzheimer's.

Newcomer et al (1999) • The aim of the research was to investigate whether high levels of the stress hormone cortisol interfere with verbal declarative memory. • Participants: All participants were employees or students at the Washington University Medical Center. They were given a clinical interview with a physician, and excluded from the sample if they were pregnant, had a history of mental illness, had suffered head trauma, or had suffered from any illness that had been treated with corticosteroids. • Procedure: Participants were placed in one of three groups • Condition 1 high level of cortisol: The participants in the high level cortisol group were given a tablet containing 160 mg of cortisol on each day of the four day experiment. This dose of cortisol produces blood levels similar to those seen in people experiencing a major stress event. • Condition 2 – low level of cortisol: The participants in the low level of cortisol group were given a tablet containing 40 mg of cortisol per day. This dose is similar to the amount of cortisol circulating in the blood stream of people undergoing minor surgical procedures such as having stitches removed. • Condition 3 - placebo group: The participants in this condition were given placebo tablets - that is, a tablet that looked like the other tablets but with no active ingredient. This was done in order to have a control group.

• Procedure All participants were asked to listen to and recall parts of a prose paragraph (tested their verbal declarative memory). It is known that verbal declarative memory is often affected during long-term stress and the researchers knew from previous studies that cortisol could be involved in memory impairment. The experiment was done under a double-blind control. • Results: The groups who had received higher cortisol had impaired performance in the memory task and the worst performance in verbal declarative memory. The effect was not permanent, however. The performance of participants in the high cortisol condition returned to normal after they stopped taking the hormone tablet. This shows a link between levels of cortisol and remembering. Cortisol interferes with the transfer of short-term memory to long-term memory that takes place in the hippocampus. This makes sense as there are several cortisol receptor sites on the hippocampus.

Diet and Learning • Inadequate food intake will limit a child’s ability to learn They become less active and show less interest in their social world They exhibit less emotional expression Combined with other factors of poverty, malnutrition may stunt a child’s cognitive development Appropriate food stimulation may modify cognitive impairment caused by earlier malnutrition Ernesto Pollitt (professor of Pediatrics at the University of California): School breakfast programs and food programs for young mothers and their children have had positive effects on cognitive development

Diet and Cognitive Development • Malnutrition may begin as a problem before a child is born. • Women who are undernourished in pregnancy have children with lower birth rates, stunted growth, and cognitive development problems • 1/3 of children from low-income communities enter kindergarten behind their peers By 4 th grade, 50% of these children do not meet standards for reading (national Center for Children in Poverty (2002) • Cook et al (1996) Children who participate in universal school breakfast programs have lower rates of absence and tardiness, which may improve cognitive development simply because they are in school • Mc. Laughlin et al (2002) Found that schools which provide universal school breakfast have higher breakfast participation, especially when it is served in the classroom and students who significantly increase their breakfast participant are more frequently in attendance and on time

Pollitt (1995) • For years psychologists have argued that poverty has an effect on a child’s cognitive development. The problem with this argument, of course, is that there are many aspects of poverty that may be the “cause” of cognitive impairment. One of the variables that has been studied by psychologists is malnutrition. • Pollitt carried out a study in four extremely poor villages in central Guatemala for a period of eight years. Because it was thought that protein was the most important nutrient missing from the villagers’ diet, it was decided to give villagers a nutritional supplement. Participants were pregnant women and children under the age of of 7. More than 2000 children and mothers participated between 1969 and 1977. • Participants in two of the villages received a high protein supplement called Atole. The inhabitants of the other two village - who served as the control group - received Fresco, which contained no protein. Both supplements provided vitamins and minerals as well as calories, but Fresco only had one-third of the calories of Atole.

• The findings showed a significant drop in infant mortality in both sets of villages, but with a 69% decrease in villages taking Atole and only a 24% decreased in the villages taking Fresco. Children on Fresco suffered a slower rate of growth and a slower rate of recovery from infection. They also learned to crawl and walk slightly later on average. Because these undernourished children remained small for their age, adults may have trended to treat them as if they were younger than their actual age. • The follow-up study was carried out in 1988, eleven years after the completion of the first study. The participants who received Atole in early life performed significantly better on most tests of cognition compared to those who received Fresco. Children from the lowest socio-economic level of the village scored just as high as those in the higher SES of the village. With every additional year of schooling, the differences in achievement between those children who took Atole vs. Fresco, increased. However, the children from the villages still performed less well than children from a middle-income household in a more prosperous area of Guatemala.

Prenatal diet • Hibbeln et al (2007) Aim: To test the effect of prenatal consumption of omega-3 fatty acids (found in seafood) and fetus neural development Procedure: Compared two groups of pregnant women (One consumed high levels of omega-3 fatty acids and the other consumed low levels) Findings: Children of those who had a low seafood intake during pregnancy had lower motor skills and lower social development and communication skills when compared to children born from mothers who had consumed higher amounts.

Diet and Development • Breakfast and development: • Raloff (1989) found that sixth graders who were given free school breakfasts improved their math and science scores over one year when compared to those who had not been given breakfast • The benefits of breakfast (Food Research Action Center, 2010) A meta-analysis of breakfast program studies in the USA Conclusions: Children who skip breakfast are less able to distinguish among similar images, show increased errors, and have slower memory recall Children experiencing hunger have lower math scores and are more likely to have to repeat work- or even an academic year Behavioral, emotional, and academic problems are more prevalent among children with hunger Children experiencing hunger are more likely to be hyperactive, absent and tardy, in addition to having behavioral and attention problems Children who are undernourished score lower on cognitive tests when they miss breakfast Teens experiencing hunger are more likely to have been suspended from school, have difficulty getting along with other children, and have no friends Children with hunger are more likely to have repeated a grade, received special education services, or received mental health counseling, than low-income children who do not experience hunger

Wertheimer 2003 • Found that children from poor families were less likely to be identified as academically gifted, more likely to repeat a year in school, less likely to be apart of extra activities, and more likely to suffer from learning disabilities compared to children who do not live in poverty

Schoon et al (2002) • Investigated long term impact of academic achievement in adult life in a British sample • Followed 30, 000 people from birth to adulthood from two cohorts (groups) of children One group born in 1958 the other in 1970 They found that children raised in poverty had an increased rick of poor academic performance, which influenced success later in life • The exact link between socio-economic background and development is not fully understood • There is a cumulative effect of positive or negative factors related to socioeconomic factors Individuals from more privileged homes have greater educational opportunities, more role models, and greater parental expectations than those from less privileged

Werner & Smith (1992) • Effects of poverty can be reversed • Carried out a longitudinal study of high-risk children and found that 1/3 of them had adjusted well to adult life

Counteracting the problem • Since we know that poverty can inhibit cognitive development what is being done? • There are programs which have been started to combat effects of poverty

Pungello et al. 2006 • Longitudinal study: Abecedarian Project • Between 1927 and 1977 program enrolled 111 infants to participate in early educational intervention Half were the experimental group, half the control group • Children received all day care throughout the year before entering kindergarten They: Played educational games focusing on developing cognitive and language skills, and received adult-child interaction through playing and talking, • Results: beneficial effects in development

Parenting • Parenting: The act of supporting a child physically, emotionally, socially, and intellectually – not biological relationship • USA Michigan Department of Education (2002) argued that the most consistent predictors of a child’s academic achievement and social adjustment were parent expectations • Family participation in education was twice as predictive of students’ academic success as family socio-economic status Parents of high- achieving students set higher standards for their children’s educational activities than those of lower achieving students. These students had: Higher grades, test scores, and graduation rates Increased motivation and better self-esteem Better school attendance Lower rates of suspension Decreased use of drugs and alcohol Fewer instances of violent behavior

What the researchers' say • Tizard et al (1982) Found that students who practice reading at home with their parents have more significant gains in reading achievement compared to those who only read in school • Moscovici (1993) Children who are loved and care of will be disciplined, given healthy good, and encouraged to be reflective and set high goals for themselves As a result they will have higher self-esteem and will do better in school and in personal relationships. • Wood et al (1976) Parents will scaffold (ZPD) good behavior for their children

Poverty and brain development • Biological factors Poor nutrition (Before and after birth) Health problems • Sociocultural factors Parenting practices Home environment • Cognitive factors Living in neighborhoods with high levels of crime/stress Parenting practices