Psychology Over the Lifespan

From conception to the elder years

In the Beginning

• Gametes are sex cells (sperm and egg) and each contain 23 chromosomes.

• Sperm penetrates the egg and its genetic material is melded with the ovum (egg).

• In the egg, one chromosome is a X (female) and in the sperm, either X or Y.

– Sperm determine sex!

Sex: Chromosomes

• XX: Female

• XY: Male

What happens next?

• The fertilized egg becomes a zygote– A zygote has 46 chromosomes (in pairs);

one member in each pair coming from the egg or sperm.

• Chromosomes are made of DNA; each of its “rungs” are formed by the bond between pairs of chemicals. Genes make up these “rungs.”

Gene Dominance

When a person possesses differing genes for the same

trait, one is often dominant over the other

Next image: Copyright Allyn & Bacon, 2003

ZygoteBlastocyst

• Next, the zygote begins to divide, and the production of certain hormones causes genes to turn on and off in a specific sequence, guiding development.

• Within 3 days, a cluster of 60-70 cells has formed a blastocyst. This rolls into a tube and proceeds through an orderly procession of stages.

• Cell images copyright Allyn & Bacon, 2003

First Division

Second Division

Fetal Development

EmbryoFetus

• An embryo is formed (from the blastocyst) within 2 weeks. All major axes of the body are present.

• A fetus is formed within 8 weeks. All major body structures are evident.

• Pregnancy is divided into 3 month intervals called trimesters.

Fetal Development

Blastocyst

Pregnancy

• By the end of the second trimester, the great bulk of the neurons are in place.

• 50% of all fertilized eggs contain some kind of abnormality. Most of these are spontaneously aborted.

• 1/250 babies are born with an evident abnormality.

The Fetus

• The fetus is active from the start! Males are more active than females.

• 20-25 weeks: sensitive to light and sound

• 28 weeks: Responds to outside stimulation

• 25-34 weeks: Can detect human speech

Teratogens: When the environment hurts

• Chicken pox or rubella: disrupts brain development

• Alcohol: Affects throughout pregnancy. Fetal alcohol syndrome.

• Heroin/cocaine: Physical defects, sleep problems, irritability & attentional problems

• Smoking: Miscarriage, lower birth weights, smaller heads, SIDS, stillbirth

Terotogens (continued)

• Caffeine (3 + cups coffee): Miscarriage, lower birth rate, irritability

• Lack of folic acid: Spina Bifida

• Pollutants: Birth defects, cancer, behavioral problems

• Excessive maternal stress: Attentional problems, anxiety

The Newborn: A Work in Progress

• The newborn has:– Sensory capacities (smell, hear range of

sounds)– Reflexes (e.g. rooting)– Temperament

• 14-21 months: inhibited baby/narrow face• Touching premature infants helps with growth

and development (50% faster growth in one study)

On Development

• All races/cultures pass through this orderly progression. Growth occurs in small spurts, and control over body comes in phases. By age 2 child has good control over limbs. Fine motor control comes later.

Following 2 slides: Copyright Allyn & Bacon, 2003

Developmental Milestones

(Data from Thomas, et al., 1970)

Temperament

Characteristic ways of responding to the environment that vary from infant to infant

(Data from Thomas, et al., 1970)

The Child

• Piaget (1896-1980): He was a Swiss psychologist that studied children’s thinking and reasoning. He developed two central concepts:– Assimilation: The child uses existing schemas

(mental structures that organize input) to take in new things and respond accordingly

– Accommodation: Changing schemas to cope with a broader range of situations.

Piaget: 4 Stages of Development

• Sensorimotor (0-2 years)

• Preoperations (2-7 years)

• Concrete Operations (7-12 years)

• Formal Operations (12 and up)

Following 4 slides: copyright Allyn & Bacon, 2003

Sensorimotor

•Understand the world through senses and motor actions

•Develop object permanence at stage end

•At 9 months, can imitate

Preoperative

•Think about things not present

•Fantasy play

•Thinking egocentric, dominated by perception

Concrete Operations

• Can manipulate ideas

• Understand reversibility

• Can do conservation and classification

Formal Operations

•Can do abstract & hypothetical reasoning

•Can reason contrary to experience

•MAY be found only in people's areas of expertise!

Adolescence

• Begins with puberty: Hormones cause sex organs to mature and secondary sexual characteristics to appear.

Copyright Allyn & Bacon, 2003

Adolescence

• Uneven growth patterns leads to awkward look; Rapid growth of hands, feet, and legs is followed by growth in the torso.

Adolescence

• Girls typically stop growing at age 13, boys age 16.

• Abstract thinking: Now can understand higher mathematics, politics, relationships. Brain continues growing.

Following slide: Copyright Allyn & Bacon, 2003

Growth

Adolesence

• Three characteristics

–Personal Fable

–The Imaginary Audience

–Peer Influence

Following 5 slides: copyright Allyn & Bacon, 2003

Personal Fable

Adolescents assume their thoughts and feelings are unique (no one has ever loved so deeply, etc.)

Personal Fable: Its Risky

Adolescents tend to engage in risky behavior they would never do as adults.

The Imaginary Audience

The strong focus on self leads adolescents to feel that everyone else is focused on them as well.

Early Maturing Boys

Late Maturing Boys

Early Maturing Girls

Late Maturing Girls

Adolescence• Conflict with parents: Most frequent early on, but

intensity peaks in late adolescence. Most often between mothers and daughters in early adolescence.

• Mood swings

• Prone to taking risks: Peaks in late adolescence.

Adolescence

• Many adolescents do not have these problems. Problems may be triggered by the environment.

Parents and Teens

• Kids value parents' advice more than peers on life goals, religion, politics, morality, use of hard drugs

• Peers more valued on questions of sex, music, styles, use of alcohol

• Kids share parents' views concerning personal values

• Parental influence highest where there is a good parent-child relationship

(Allyn & Bacon, 2003)

Aging

• Problematic changes from the environment– Lack of nutrition– Lack of exercise– Lack of meaningful activities

• Sexual changes.– Women: Menopause (44-55yrs)– Men: declining strength/energy can affect

sexual performance.

Aging

• By age 50, some decline in cognitive abilities (perhaps disturbed neurotransmitter function or degrading white matter).

• More than 50% 65+ has cataracts.– Narrowing of pupil makes light/dark contrast

hard.

Aging

• Past age 50, lose ability to hear high frequency sounds.

• Smell declines after middle 50s.

What about memory?

Aging

• Semantic memory (facts, words, meanings) and new episodic memories (specific events) remains intact.

• Decline in working memory(short-term) due to frontal lobe impairment.

Aging

• Fluid and crystallized intelligence until mid-50s and in the early 70s both decline.– Fluid intelligence: Flexibility in reasoning– Crystallized: Facts, vocabulary

Aging

• The good stuff:

– Wisdom– More emotional stability– Socioemotional selectivity theory– Cerebral reserve hypothesis

• Compensation for declining abilities

Lets look at a lifelong developmental model

Erickson’s Psychosocial Development

• Basic Trust vs. Mistrust (0-1yrs): Infants either develop a basic trust that the world is good or fail to do so.

• Autonomy vs. doubt (1-3 yrs): The child either is allowed to make independent decisions or made to feel ashamed/self-doubt for wanting to do so.

Erikson

• Initiative vs. Guilt (3-6 years): Develop a sense of purpose or direction, or is overly controlled by parents and made to feel constrained or guilty.

• Industry vs. Inferiority (6-11yrs): Develop competence and ability to work with others, or feel inferior and incompetent

Erikson

• Identity vs. role confusion (adolescence): Either successfully grapples w/questions of identity and future roles or becomes confused.

• Intimacy vs. Isolation (young adult): Develops deep, intimate relations or is socially isolated

Erikson

• Generativity vs. Self-absorption (middle adulthood): Look toward the future and determine what to leave as legacy; failing to do so leads to meaninglessness

• Integrity vs. Despair (old age): Reflect back and think life was worthwhile or feels despair and fears death.

End of Developmental