Development & Mental Health
Lecture 1
Why do we study human development?
How to raise healthy people in a society influence on social policies
Use of children in a court of law How can children
Understanding human nature:
Developmental research contributes to
Biology has an important impact on development: Nature/nurture, prenatal
development, etc.
Children shape their own development:
- Newborns:
Prefer things that move and make sounds, and pay particular attention to the
mothers’ face.
- Toddlers: 1-2 years
Internally motivated to learn and practice talking: use op self-speech
- Younger children:
Engage internally motivated play, fantasy play, dramatic play to support their
development.
- Older children:
Use more organized, rule-bound play to enhance self-control and social
development.
The active child: Play
Children contribute to their own development from early in life, and their contributions
increase as they grow older. Three of the most important contributions during a child’s
first years are
1. Attentional patterns
2. Use of language
3. Play
Older children and adolescents choose environments, friends, and activities
themselves: Their choices impact their future.
Continuous development: Changes with age occur gradually, in small increments.
Development occurs skill by skill and task by task
Discontinuous development: Changes with age include large shifts, where qualitative
di erences occur. Piaget, Freud, Erikson and Kohlberg
,Chapter 3 / Lecture 2
Nature/nurture debate
Nature: Genes that predict.
Nurture: environment and culture that predict.
Complex interactions among genetic and environmental factors will be organized in
three key elements:
- Genotype: inherited genetic material
- Phenotype: observable expression of the genotype (both physical and
behavioral characteristics)
- Environment: every aspect of an individual and their surroundings
1. Parents Genotype Child’s Genotype
The nucleus of each human cell contains
chromosomes consisting of two strands of
DNA. These carry instructions known as genes,
sections that are the basic unit of living.
Humans have 23 pairs of two chromosomes,
and each pair carries genes of the same type.
Of these two copies of each gene, each parent
passes on one chromosome to their o spring.
Variation in this is crossing over (when
gametes divide and the two members of a
chromosome swap sections of DNA), which
results in a di erent constitution of
chromosomes between parent and child, and
mutation (a change in a section of DNA, as a
spontaneous error or result of environment),
which result in inherited disorders.
Sex determination is handled by sex Figure 1: Development as a combined function of genetic and
environmental factors
chromosomes. Women have XX chromosomes,
and men have XY chromosomes. This means that the gender of a baby is decided by the
man’s sperm, because women can only produce eggs with an X chromosome.
X chromosomes carry more genes than Y chromosomes
[practice / study this!!]
, 2. Child’s Genotype Child’s Phenotype
Genes also influence unobservable aspects of the phenotype, such as our brain and
nervous systems. These intermediate phenotypes are also called endophenotypes
(endo = inside). These mediate the passways between genes and behavior.
Only some of the genes you inherit can be expressed. Some are active, and some are
not. Genes influence an individual's development only if they are switched on and o in
the right place. This is controlled by regulator genes. When one gene is switched on, it
causes another gene to turn on or o . It is a part of a genetic event.
external factors such as vision also a ect the switching of genes.
Many genes are never expressed, only carried. Genes like hair color can have multiple
forms, or alleles. These influence di erent developmental outcomes.
Dominant-recessive pattern:
One allele is dominant, and one is recessive. In this, there are two possibilities.
1: a person inherits two of the same alleles (homozygous). 2: a person inherits
two di erent alleles (heterozygous). In this case, the dominant allele takes over.
Often, inheritance patterns are more complicated than this. Intelligence is linked to
about 500 di erent genes. These follow a polygenic inheritance pattern. So you
should be skeptical when seeing the discovery of a gene for a complex human trait.
3. Child’s Environment Child’s Phenotype: gene x environment interaction
How does the environment a ect the child’s phenotype? One example of this is
phenylketonuria (PKU). Individuals who inherit this gene can’t metabolize
phenylalanine, which is found in many foods. This can lead to impaired brain
development. A genotype can thus lead to di erent phenotypes depending on the
environment.
MAOA gene (x-linked): Inhibits brain chemicals linked to aggression. With low levels of
MAOA activity, individuals are more likely to develop antisocial behavior.
, Carrier genetic testing: genetic testing used to determine whether prospective
parents are carriers of specific disorders. Mostly done on people from non-
western descent.
Prenatal testing: genetic testing used to access the fetus’s risk for congenital
abnormalities. This is done through analyzing the parent’s blood, DNA or
placenta.
Newborn screening: tests used to screen newborn infants for a range of
disorders. This is done through blood tests.
Parents own genetic makeup influences the environment parents provide for their
children. Behavior is genetically influenced, as are the kinds of preferences, activities
and resources to which they expose their children (parents who don’t like reading will
o er less books to their children).
This idea was tested, and it was revealed that by a ecting the parents’ phenotypes, the
parents’ genes a ected their children’s educational success. Educational outcomes
were predicted by parental alleles that the child did not inherit. These play a role in the
child’s environment (genetic nurture).
4. Child’s Phenotype Child’s environment
A child evokes a certain kind of response from others. An outgoing child will fill its
environment with people smiling and talking to him. A shy child will only attract
attention from those he knows. Two children from the same genes can thus have a
di erent environment.
Children also actively select surroundings and experiences that match their interest.
They choose playmates they enjoy, and do the things that they like.
5. Child’s Environment Child’s Genotype
The field of epigenetics, stable changes in gene expression that are mediated by the
environment, shows that the environment does change our genes. Genetic code
remains “fixed”, but epigenetic mechanisms can alter the functioning of genes and
create stable changes in their expression.
Methylation is mostly studied, which is the silencer of gene expression. These block
transcription in the promoter region of the gene, turning o activity. Methylation
provides evidence for long term epigenetic e ects on gene expression, impacting later
health.
Lecture 1
Why do we study human development?
How to raise healthy people in a society influence on social policies
Use of children in a court of law How can children
Understanding human nature:
Developmental research contributes to
Biology has an important impact on development: Nature/nurture, prenatal
development, etc.
Children shape their own development:
- Newborns:
Prefer things that move and make sounds, and pay particular attention to the
mothers’ face.
- Toddlers: 1-2 years
Internally motivated to learn and practice talking: use op self-speech
- Younger children:
Engage internally motivated play, fantasy play, dramatic play to support their
development.
- Older children:
Use more organized, rule-bound play to enhance self-control and social
development.
The active child: Play
Children contribute to their own development from early in life, and their contributions
increase as they grow older. Three of the most important contributions during a child’s
first years are
1. Attentional patterns
2. Use of language
3. Play
Older children and adolescents choose environments, friends, and activities
themselves: Their choices impact their future.
Continuous development: Changes with age occur gradually, in small increments.
Development occurs skill by skill and task by task
Discontinuous development: Changes with age include large shifts, where qualitative
di erences occur. Piaget, Freud, Erikson and Kohlberg
,Chapter 3 / Lecture 2
Nature/nurture debate
Nature: Genes that predict.
Nurture: environment and culture that predict.
Complex interactions among genetic and environmental factors will be organized in
three key elements:
- Genotype: inherited genetic material
- Phenotype: observable expression of the genotype (both physical and
behavioral characteristics)
- Environment: every aspect of an individual and their surroundings
1. Parents Genotype Child’s Genotype
The nucleus of each human cell contains
chromosomes consisting of two strands of
DNA. These carry instructions known as genes,
sections that are the basic unit of living.
Humans have 23 pairs of two chromosomes,
and each pair carries genes of the same type.
Of these two copies of each gene, each parent
passes on one chromosome to their o spring.
Variation in this is crossing over (when
gametes divide and the two members of a
chromosome swap sections of DNA), which
results in a di erent constitution of
chromosomes between parent and child, and
mutation (a change in a section of DNA, as a
spontaneous error or result of environment),
which result in inherited disorders.
Sex determination is handled by sex Figure 1: Development as a combined function of genetic and
environmental factors
chromosomes. Women have XX chromosomes,
and men have XY chromosomes. This means that the gender of a baby is decided by the
man’s sperm, because women can only produce eggs with an X chromosome.
X chromosomes carry more genes than Y chromosomes
[practice / study this!!]
, 2. Child’s Genotype Child’s Phenotype
Genes also influence unobservable aspects of the phenotype, such as our brain and
nervous systems. These intermediate phenotypes are also called endophenotypes
(endo = inside). These mediate the passways between genes and behavior.
Only some of the genes you inherit can be expressed. Some are active, and some are
not. Genes influence an individual's development only if they are switched on and o in
the right place. This is controlled by regulator genes. When one gene is switched on, it
causes another gene to turn on or o . It is a part of a genetic event.
external factors such as vision also a ect the switching of genes.
Many genes are never expressed, only carried. Genes like hair color can have multiple
forms, or alleles. These influence di erent developmental outcomes.
Dominant-recessive pattern:
One allele is dominant, and one is recessive. In this, there are two possibilities.
1: a person inherits two of the same alleles (homozygous). 2: a person inherits
two di erent alleles (heterozygous). In this case, the dominant allele takes over.
Often, inheritance patterns are more complicated than this. Intelligence is linked to
about 500 di erent genes. These follow a polygenic inheritance pattern. So you
should be skeptical when seeing the discovery of a gene for a complex human trait.
3. Child’s Environment Child’s Phenotype: gene x environment interaction
How does the environment a ect the child’s phenotype? One example of this is
phenylketonuria (PKU). Individuals who inherit this gene can’t metabolize
phenylalanine, which is found in many foods. This can lead to impaired brain
development. A genotype can thus lead to di erent phenotypes depending on the
environment.
MAOA gene (x-linked): Inhibits brain chemicals linked to aggression. With low levels of
MAOA activity, individuals are more likely to develop antisocial behavior.
, Carrier genetic testing: genetic testing used to determine whether prospective
parents are carriers of specific disorders. Mostly done on people from non-
western descent.
Prenatal testing: genetic testing used to access the fetus’s risk for congenital
abnormalities. This is done through analyzing the parent’s blood, DNA or
placenta.
Newborn screening: tests used to screen newborn infants for a range of
disorders. This is done through blood tests.
Parents own genetic makeup influences the environment parents provide for their
children. Behavior is genetically influenced, as are the kinds of preferences, activities
and resources to which they expose their children (parents who don’t like reading will
o er less books to their children).
This idea was tested, and it was revealed that by a ecting the parents’ phenotypes, the
parents’ genes a ected their children’s educational success. Educational outcomes
were predicted by parental alleles that the child did not inherit. These play a role in the
child’s environment (genetic nurture).
4. Child’s Phenotype Child’s environment
A child evokes a certain kind of response from others. An outgoing child will fill its
environment with people smiling and talking to him. A shy child will only attract
attention from those he knows. Two children from the same genes can thus have a
di erent environment.
Children also actively select surroundings and experiences that match their interest.
They choose playmates they enjoy, and do the things that they like.
5. Child’s Environment Child’s Genotype
The field of epigenetics, stable changes in gene expression that are mediated by the
environment, shows that the environment does change our genes. Genetic code
remains “fixed”, but epigenetic mechanisms can alter the functioning of genes and
create stable changes in their expression.
Methylation is mostly studied, which is the silencer of gene expression. These block
transcription in the promoter region of the gene, turning o activity. Methylation
provides evidence for long term epigenetic e ects on gene expression, impacting later
health.
