Presentation on theme: "Developmental Psychology. Nature versus Nurture Maturation: the unfolding of behaviors that are genetically programmed for all humans. Timing may."— Presentation transcript:
Nature versus Nurture Maturation: the unfolding of behaviors that are genetically programmed for all humans. Timing may vary slightly from child to child. Learning: a systematic change in behavior as a result of experience.
Research Methods Observation: used extensively but doesn’t lend itself to control. Laboratory experiments: often lacks ecological validity. Case studies: ethical considerations may arise. Longitudinal research: researchers like to look at how behaviors may change over time. Limitations include time and the fact that participants may drop out.
Cross-sectional design: comparing two or more groups on a particular variable. For example comparing subjects of different ages. Much less time consuming. Limitation may be that you can’t be sure that differences aren’t due to participant variable.
Earlier in this course, we saw that babies seem to be born with certain behaviors. Reflexes such as grasping, rooting, and suckling. Basic auditory and visual abilities; such as a preference for human faces and voices. An ability to communicate through movements and sounds, almost like a conversation. Possibly due to mirror neurons. An attraction to novelty and the seeming ability to recognize physically impossible actions.
Brain Development The brain of a newborn has more than a trillion neurons. Synaptic growth happens at a very rapid pace throughout the first year, though it continues throughout life. This ability for the brain to develop and change due to the environment is called neuroplasticity. PET scans allow researchers to investigate brain development by looking at glucose metabolism in different areas, showing where the brain is most active.
Chugani (1999) found that in newborns, there was little activity in the cerebral cortex where higher level mental functions occur. He found that most activity was in the brain stem and thalamus where reflex activity is controlled. He also found that the limbic system, associated with memory, emotions, and bonding also showed signs of higher activity. Bachevalier et al (1999) found that brain lesions in these areas led to less bonding in monkeys. They showed less eye contact and blank facial expressions. He hypothesized that autism may be related to damage in these areas.
Chugani’s research showed that from 6 to 9 months, the frontal lobes and the prefrontal cortex began to show much more activity. He also found that some lower areas of the brain, such as the hippocampus, that are associated with memory become more active. PET scans show that glucose metabolism increases steadily where it reaches adult levels at around two years. From two years to adolescence it actually exceeds adult levels leading to an excess of synaptic connections. The unnecessary connections are then lost in a process known as pruning.
Case (1991) hypothesized that the brain changes taking place between 5 and 7 years of age enables the frontal lobe to take on more of the executive functions. Evidence supporting this comes from observations of brain damaged patients. During adolescence the brain continues to develop but at a slower pace. Myelinization and reorganization takes place, especially in the prefrontal cortex, and allows the brain to function more rapidly and more efficiently.
Gledd (2004) said that the area that controls impulses, located in the prefrontal cortex, was one of the last to develop, at around age 20. He undertook a longitudinal study using MRI scans every two years. He found that 95% of brain structures were developed by around 5 or 6 years old but that just before puberty there was another growth spurt of synaptic activity in the frontal lobes. His research showed that the prefrontal cortex was relatively late in development. Though research has made a lot of progress, most researchers feel that we do not really know enough to make educational or policy decisions based on the current neuroscience.
Piaget and Cognitive Development Jean Piaget took what is known as a constructionist approach to understanding cognitive development. He felt that cognitive development happens through a combination of maturation and the way that a child interacts with the social and physical world. He said that the strategies in thinking used by children reflect different stages of development.
Piaget developed a method using questioning and observation which he called a clinical interview. He used this method to provide insight into a child’s judgments and explanations of things. He theorized that knowledge consists of schemas, or cognitive structures used to help a child figure out how to deal with the world. He felt that all children are born with basic schema such as sucking, reaching, and grasping and that these were modified based on experience. He called the process by which a child constructs new schema or knowledge adaptation.
He said that adaptation has two basic forms. Assimilation: Fitting new information about the world into our schema (the way we understand the world to be). Accommodation: Change our schema to fit the world. Piaget’s Stages (How children think ) Sensorimotor Stage (Birth to age 2 ) : Thinking in terms of actions (motor) and feelings (sensations). Schemes are very self-centered. Representational thought: the ability to picture things in your mind. Object permanence: the realization that something still exists even though we don’t see it.
Preoperational Stage: (Ages 2-7) Symbolic representation begins. Language begins to develop. They can draw but cannot use reasoning solve problems. They have egocentric thinking (they cannot take another’s point of view). Concrete Operational Stage: (Ages 7-12) Understand conservation (the ability to understand that things can be the same yet look differently) and dimensions. Use logical schemes, but limited to concrete problems. Can add with apples, but not numbers at first. Gradual movement to more abstract problem solving. Formal Operational Stage: 12-adult. Abstract and hypothetical thinking begins. Some (many?) never really make it very far into this stage.
Challenges to Piaget’s theory Siegler, 1996, found that cognitive abilities develop in overlapping waves rather than discrete steps showing that the changes from one stage to another are neither as clear-cut nor as sweeping as Piaget implied. Children can understand far more than Piaget gave them credit for. Baillargeon, 1991, showed babies much younger than Piaget said start forming object permanence. DeLoache, 1995 showed a much earlier version of symbolic thought.
Preschoolers are not as egocentric as Piaget thought. Flavell, 1993, showed that children can take another persons perspective. Shatz and Gelman, 1973, showed that children will modify their language when talking to a younger child. They develop a theory of mind, a system of beliefs about how their own and other people’s minds work. They start to ask why some people act like they do. Others argue that Piaget underestimated the role of social learning in development.
Vygotsky A Russian psychologist who emphasized a sociocultural approach to cognitive development. He said that children learn in the context of their culture by interacting with others. He referred to the zone of proximal development which distinguishes between what a child can do on its own and what it can do with help. He said that children can use scaffolding, receiving assistance to perform a task slightly beyond their current level, to increase their competency.
Social and environmental factors on cognitive development. Poverty has been shown to be one of the major risk factors in a child’s cognitive development. Poor nutrition, higher levels of stress, parenting practices all have an effect.. According to the National Center for Children in Poverty, one-third of children from low-income communities start kindergarten behind their peers.
Social Development Attachment behavior : a behavior pattern where infants of most mammals seek proximity to the mother and react with anxiety to separation from her. Seen by most researchers to have an evolutionary basis which is innate and helps infants to survive. Harlow’s monkey experiments gave early support to this idea of an innate need for attachment.
Psychoanalytic theory holds that early childhood experiences, especially concerning relationships with the mother, have major impacts on a person’s entire life. John Bowlby spent most of his career working with children who were separated from their parents during World War II. He observed that many of these children developed emotional problems and related it to separation from the mother. He claimed that the damage was permanent and irreversible.
Bowlby said that attachment behavior is characterized by: Proximity maintenance : a desire to be near the person to whom the baby is attached, usually the mother. Safe haven : a desire to return to the figure for comfort and safety in the face of distress. Separation distress : reacting with distress when separated form the attachment figure. The attachment figure acting as a secure base for the child.
Bowlby also says that children develop a cognitive schema of expectations concerning the attachment figures called an internal working model which includes three important elements. Ideas about attachment figures and what can be expected from them Ideas about the self Ideas about how the self and others relate. If the child receives love and affection, he or she comes to see him or her self as being worthy of love and affection. He says this will affect the child’s other relationships throughout their life.
Shaffer(1996) found that attachment develops until around 7 mths where signs indicate a specific attachment has occurred. Brazleton et al. (1975) did an observational study and found that both the mothers and the babies imitated each other’s movements and emotional expressions. He called this interactional synchrony and attributed some of it to mirror neurons. He argued that maternal sensitivity is important to the attachment process and found that children become very upset when caregivers do not respond to the child’s signals.
Ainsworth and the strange situation paradigm. Mary Ainsworth (1970) developed an experimental procedure called the strange situation which resulted in a classification of attachment patterns. She started her work with a longitudinal study known as the Ganda project (1967) in Uganda. She followed this up with a replication in Baltimore, Md. In 1971. Her research resulted in a classification system which is still used today.
Strange Situation Classification (SSC) Type A – Avoidant (20% of children): the child shows indifference when the mother leaves the room and avoids contact when she returns. They are not afraid of strangers. Their mothers tend to be insensitive and do not seem interested in the child’s play. Type B – Securely attached (70% of children): the child is upset when the mother leaves and happy to see her return. They are easily comforted by the mother. Their mothers are very interested in the child and actively support play and communication. Type C – Ambivalent (10% of children): the child is very upset when the mother leaves but is not easily comforted upon return. Their mothers are inconsistent with their reactions to the child.
Another attachment type suggested by Main and Solomon (1986) is now included. Type D – insecure-disorganized/disorientated: the child shows no particular reaction when the mother leaves or comes back. This type has been associated with childhood abuse. There are several factors involved in the development of attachment. Parental sensitivity: Ainsworth’s research indicates that sensitive mothers tend to have securely attached babies. Infant temperament: Kagen(1982) argues that the child’s innate temperament influences how those in the environment interacts with them. He says that the strange situation paradigm actually measures temperament more than attachment.
Family circumstances: abusive situations, sudden poverty, or bereavement can all have an affect on how much support the child get’s which can cause fluctuations in the type of attachment a child displays. Cultural influence on attachment. Various cultures have differing child rearing practices and different norms that can influence attachment. Ijzendoorn and Kroonenberg (1998) reviewed 32 studies from 8 countries using over 2000 infants and found major differences in the distribution of attachment types. Japanese showed no type A and a large number of type C.
The role of attachment in latter relationships. Bowlby predicted, in typical psychoanalytic fashion, that childhood attachment would have an impact on adult love relationships. Hazan and Shaver (1987): felt that the early attachment patterns would form expectations and beliefs about relationships. They devised a “love quiz” which would translate Ainsworth’s attachment types to adult relationships.
Effects of deprivation or trauma in childhood on later development. Almost everyone agrees that early deprivation or trauma can have major effects on development and therefore, later life. What somewhat surprised many was how resilient some children turn out to be. Resilience refers to the ability to recover or bounce back from even extremely stressful events.
A self-selected sample (it was published in a newspaper) of 620 people responded. The results showed that 60% of respondent showed a secure attachment style, 20% showed the anxious- avoidance pattern, and 20% showed the anxious- ambivalent pattern. The also asked participants to describe their parent’s parenting styles by choosing adjectives People who were securely attached said their parents had been readily available, attentive and responsive. People who were anxious-avoidant said their parents were unresponsive, rejecting and inattentive. People who were anxious-ambivalent said their parents were anxious and only sometimes responsive.
Schoon et al. (2002): resilience should be seen as a positive adaptation, not as a personality attribute. Rutter (1981): the consequences of early adversities are to a large extent dependent on the nature of subsequent life experiences. Three major factors seem to be particularly important in building resilience: The temperament of the child A close relationship with at least one parent (or parental substitute. Social support of the community.
Strategies for building resilience One of the most critical factors is to build a healthy relationship between the child an a parental figure. Many resilience programs include parent education. Home visit programs Teen mother parenting classes Head-start programs After school programs. Another major factor is timing. Early interventions work much better than those started later in life.
Identity Development The formation and development of gender roles. The 1 st thing anyone asks about a new child that is born is whether it is a girl or a boy. Once the appropriate label is attached it will affect how everyone will treat them for the rest of their lives. Nearly every society defines different roles for males and females, from childhood on. Gender identity: the ability to identify the gender or sex of oneself and others correctly. Happens around 2 years old for most children.
Gender Constancy: the realization that your gender will stay the same, no matter what kind of clothes you wear. This happens at around 7 years of age. Gender Roles: the typical or appropriate behaviors, according to gender, that is expected of men and women. This is an area where the nature-nurture issue has long been hotly debated. Do basic biological and hormonal factors lead to differences seen in males and females, or is the way we are treated from birth?
Biological Explanations Theory of psychosexual differentiation During prenatal development whether or not the male hormones (androgens) are present determines whether the fetus will develop male or female sex organs. Some argue that testosterone has a masculinization effect on the brain of a developing child. This theory says that children are born with innate predispositions to act and feel like males or females. This has been shown by injecting testosterone into female rat fetuses.
Biosocial Theory of Gender Development. This theory was introduced by Money and Ehrhardt in 1972 and basically states that socialization is the most important factor in gender identity. It acknowledges hormonal influences but says that the way the child is socialized is most important. Based on case studies of intersex individuals (those born with ambiguous genitals). He found that these children could be operated on and assigned a particular sex and they would grow up to be happy healthy adult men or women.
Many doctors throughout the world still do this kind of surgery, even though the research is based on limited case studies. One of the most famous case studies actually indicates that this can be problematic. David Reimer was born a boy (notice he was not unisex). At seven months old his penis was burnt off in an accident during circumcision. He was operated on an made a female, Brenda. Money did the surgery and declared it successful. Years later, David revealed that he never really felt like a girl and decided to live as a boy. He had reconstructive surgery to have a penis. He ended up marrying a woman.
Social learning theory and gender roles. Direct tuition: the learning of gender roles based on being rewarded for some behaviors and punished for others. Another factor is modeling of behavior demonstrated by same-sex models. Fagot(1985) did an observational study and showed that children act as “gender police”. Strength of the theory is that it looks at both the social and cultural context in which gender roles develop. There are also weaknesses of the theory. It cannot explain the varying degrees to which people conform. It suggests that gender is passively acquired.
Gender Schema theory A gender schema is a mental representation of the roles and behaviors associated with each particular gender. It is built upon experience and leads to a gender identity. Once the identity is established, the schema is used for subsequent information processing. Martin and Halvorson (1978) said that children have schemas for what is suitable for both girls and boys. Once gender identity is established they have an in- group and an out-group and generally categorize based on those groups.
Gender schema theory has strengths: It explains why children’s gender roles do not change after middle childhood. It depicts children as actively trying to make sense of the world. It also has limitations. There is too much focus on the individual child, leaving out social and cultural factors. It is not possible to explain how the schemas develop.
Sociocultural influences on development of gender roles. Almost every culture throughout history have had different roles for males and females. These probably came about as a consequence of childbearing and body strength. Social Role Theory: gender stereotypes arise from the differing roles men and women usually occupy. Williams and Best (1990) said that gender stereotypes are used to provide norms to use in gender socialization. Margaret Mead (1935) said that gender roles were almost completely cultural. She studied New Guinea tribes and found vast difference in gender roles in 3 different tribes.
Adolescence and identity development At about the time of puberty, adolescents go through a large amount of physical changes. Growth spurts often lead to asynchrony and make some feel awkward. The distribution of fat and muscle changes leading many to feel uncomfortable in their own bodies. The cultural ideal hypothesis, Simmons and Blyth (1987) states that many compare their bodies to the cultural ideal and come up short, causing problems with self-image.
Although everyone goes through the same changes, they can occur in different orders and at different times. Boys who go through puberty early seem to benefit socially and in self image due to increase in muscle mass which puts them at an advantage in things like sports. Girls seem to benefit more from going through puberty later. Often girls who mature early physically have not matured as much emotionally and fall prey to older males.
Erik Erikson wrote Childhood and Society (1950) where he outlined Psychosocial Stages that people go through in life. The fifth stage concerns adolescence. He said this a period of identity crisis which he termed the identity versus role confusion stage. He placed a lot on emphasis on the idea that this is a time where people are trying to not only figure out who they are, but what they want to be. He called this a moratorium, a time to explore different possibilities. He says that if one goes through this stage successfully, they come out feeling confident of what they want out of life. If not he says it can lead to role confusion.
He also says that a successful completion of this stage is vital in the next stage, which he calls intimacy versus isolation. When a person commits to another person.