Human Development:Nature

Jennifer Boyd, M.S.

Developmental Psychology

The systematic study of how humans grow, develop, and change

throughout the lifespan.

Nature v. Nurture

Develop – the process of natural growth, differentiation, or evolution by

successive changes.

Part I: Nature

• Genetics & Genes• Heredity• Chromosomes• Developmental

Disorders• Congenital Disorders• Pre-natal

Development• Biology

(Predispositions)

Part II: Nurture

• Cognition• Environment• Caregiver’s• Attachment• Post-Natal factors• Education• Culture• Religion• Nutrition

Nature v. Nurture

Biological Influences Genetics—the branch of biology that deals with heredity; study of

genes and how they influence biological development.

• Genes—A unit of DNA on a chromosome that encodes instructions for making a particular protein molecule; the basic unit of heredity.

Heredity—the sum of the characteristics; the genetic transmission of characteristics from parent to offspring.

• Chromosome—DNA-containing structure that make up the genes; located in the nucleus of a cell. 22 pairs autosomes, & 1 pair sex chrom.

Sex Chromosome—associated with male or female sex characteristics; governs the inheritance of various sex-linked and sex-limited characteristics

XX = femaleXY = male

A karyotype is a representation of chromosomal characteristics

XX = female

XY = male

Developmental Disorders: An abnormality or disruption of the normal

process of development

Disorder’s we will cover:

•Androgen Insensitivity Syndrome

•Kleinfelter’s Syndrome

•Turner’s Syndrome

•Down Syndrome

•Fetal Alcohol Syndrome

2 Systems of Gonad Development

1. MÜllerian System—embryonic precursors of the female internal sex organs (ovaries); needs no stimulus to start developing.

2. Wolffian System —embryonic precursors of the male internal sex organs (testes); needs stimulus from SRY. **If any step in this system goes awry, nature will abandon this system, and resort to the MÜllerian System.

– SRY —gene on Y chromosome that instructs fetal gonads to become testes (leads to developing androgen)

– Anti-MÜllerian Hormone —peptide secreted by fetal testes that inhibits the development of the MÜllerian system, which would otherwise become female internal sex organs. If this is not fully working, the Wolffian System can degenerate.

– Androgen—Male sex hormone; testosterone is the principal mammalian androgen; needed to develop external sex organs of the male. If there is not enough being produced, external organs may partially develop or not develop at all.

Androgen Insensitivity Syndrome

AISGenetic disorder that makes XY fetuses insensitive to

androgens

Types: CAIS (Complete Androgen Insensitivity Syndrome) 46, XY MAIS (Mild Androgen Insensitivity Syndrome) 46, XY PAIS (Partial Androgen Insensitivity Syndrome) 46, XY

Externally – female, with a short-blind pouch vagina and breasts.

Internally—male; undecended testes (because of SRY). No female organs (i.e. ovaries, uterus, fallopian tubes).

Genotype: XY (Male)Phenotype: Female

Characteristics:

Long, well-developed legs

Greater than average height for a female

Flawless complexion (no hormone-driven acne at puberty)

Physique often more angular and "athletic" than average female

Genotype: XXY or XXXYIncidence:1/1000 malesCharacteristics:

Infertility, no production of sperm, enlarged breasts, small firm testicles, small penis, sparse facial and body hair. Abnormal body proportions (long legs and a short trunk).

Kleinfelter’s Syndrome

Genotype: XO (monosomy X)

Incidence:1/2500 malesCharacteristics:

Physical abnormalities like short stature, broad chest, low hairline, low-set ears, and webbed neck. Infertility and amenorrhea persists. Usually 90% of fetuses with Turner’s result in miscarriage.

Turner’s Syndrome

Genotype: XX, or XY (trisomy 21)

Incidence:1/800 babiesCharacteristics:

Chromosomal abnormality (congenital, not inherited).

Correlated with older parental age (maternal).

Brain is 10% lighter; mental retardation is usually present.

Brain degenerates around age 30 (symptoms mimic Alzheimer’s).

Down Syndrome

Types: FAS, ARND, and ARBD

Facts:1/8 pregnant women report alcohol

use (CDC, 2011).

No distinct amount of alcohol causes FASD.

Alcohol disrupts the normal brain development by interfering with neural adhesion protein, which guides neurons in the brain to develop

Fetal Alcohol Spectrum Disorders (FASD)

Characteristics:

• Abnormal facial features, such as a smooth ridge between the nose and upper lip (this ridge is called the philtrum)

• Small head size• Shorter-than-average height • Low body weight• Poor coordination• Hyperactive behavior • Difficulty paying attention• Poor memory• Difficulty in school (especially

with math)• Learning disabilities• Speech and language delays• Intellectual disability or low IQ• Poor reasoning and judgment

skills• Sleep and sucking problems as a

baby• Vision or hearing problems• Problems with the heart, kidneys,

or bones

Prenatal Developmentpage 258

• Period of Cleavage (Zygote Stage)1-2 weeks

• Period of the Embryo (Embryonic Stage)3-8weeks**Most crucial stage

• Period of the Fetus (Fetal Stage)9-28 weeks

Neonatal Development• Reflexes—built in (programmed) survival responses.

• Perception and Motor Development.

Temperament—hereditary behavioral style or characteristic way of responding to environment.

3 Types:EasyDifficultSlow-to-Warm up

• Language – Noam Chomsky suggests that we are biologically programmed to learn and use language.

Part II: NurtureJean Piaget’s Cognitive Development

1.Sensorimotor (0-2 years)• Senses & learning; object permanence

2.Preoperational (2-7)• Pretend, Egocentric, etc.

3.Concrete Operational (7-11)• Logic abstract, conservation, etc.

4.Formal Operational (11/12+)• Logic concrete, systematic, world.

Erik Erickson Psychosocial

Developmental Stages1. Trust v. Mistrust (Birth-1 yr)2. Autonomy v. Shame and doubt (1-3)3. Initiative v. Guilt (3-6)4. Industry v. Inferiority (6-puberty)5. Identity v. Role confusion (adolescence)6. Intimacy v. Isolation (young adult)7. Generativity v. Stagnation (middle age)8. Ego integrity v. Despair (late adulthood)

P. 251

Maria Montessori• 1st female doctor in Italy.• Opened first school 1907, Casa dei

Bambini.• Studied “uneducadable” or “unhappy

little ones” (i.e. children with MR)• Developed methods and pedagogy that helped bring these children to above average.

“Our aim is not only to make the child understand, and still less to force him to memorize, but so to touch his imagination as to enthuse him to his innermost core”.

Montessori SchoolsV.

Traditional SchoolsPast & Present

Attachment

• Harry Harlow– Separation Anxiety & Stranger Anxiety

Mary Ainsworth– Quality of Attachment, 4 Patterns:

• Secure, avoidant, resistant, and disorganized/disoriented

Lifespan Development& Caregiving

Socialization—process of learning socially acceptable behaviors, attitudes, and values.

Parental Styles– Authoritarian– Authoritative– Permissive

Death and Dying Elisabeth KÜbler-

Ross5 Stages of Death:

DenialAngerBargainingDepressionAcceptance

• Cultures and religion• Terminally ill

– Passive v. Active euthanasia

• Counseling & Hospice Care• Dignity v. Despair

Text Readings

• Lev Vygotsky, page 246

• Erikson Psychosocial Stages, page 251

• Negative Influences on Prenatal Development, page 253

• Temperament and Attachment, pages 256-258

• Peer Relationships, page 261

Group Discussion

Can we increase Intelligence using in-utero techniques?

What are the Pros and Cons of Gene Therapy?

What dictates Gender Roles?– Nature (androgens, genetics)– Nurture (toys, modeling, etc)