Introduction to Human Development

• Humans are natural observers of age-related changes and stable characteristics.
• Developmental pathways result from personal characteristics, choices by others, and self-decisions.

Introduction to Human Development

• Human development is the scientific study of age-related changes in behavior, thinking, emotion, and personality.
• Philosophers historically tried to explain age-related differences.
• The scientific methods used by early pioneers in the study of human behavior, were then applied to questions about age-related change.
• Behavioral scientists in the 2nd half of the 20th century recognized age-related changes occur across the entire human lifespan.
• Efforts led to categorizing key issues and the data reveals a wealth of data suggesting that human development is a highly complex process.

Philosophical and Scientific Roots

• Early philosophers based ideas about development on spiritual authorities, philosophical orientations, and deductive logic.
• People turned to science in the 19th century to understand human development better.

Original Sin, Blank Slate, and Innate Goodness

• Philosophers focused on why similar babies develop differently, concerned with moral dimensions.
• Augustine of Hippo's original sin doctrine taught humans are born selfish and require spiritual rebirth and religious training.
• Developmental outcomes result from the struggle to overcome acting immorally for personal benefit.
• John Locke's 17th-century empiricism claimed children's minds are blank slates, with differences attributable to experience.
• The blank-slate view suggests adults can mold children, explaining adult differences.
• Jean-Jacques Rousseau's innate goodness view stated humans are naturally good and seek growth experiences.
• Good outcomes occur when a child's environment allows them to nurture their own development.
• Poor outcomes arise from frustration in expressing innate goodness.
• The innate-goodness and original-sin approaches view development as a struggle between internal and external forces
• The blank-slate view sees the child as a passive recipient of environmental influences.

Early Scientific Theories

• The 19th century saw an explosion of interest in how scientific methods might be applied to questions previously considered philosophy.
• Charles Darwin suggested life-forms evolved gradually through environmental and genetic interplay.
• Studying children's development might help understand the evolution of humans.
• Darwin and others kept detailed records of their children's early development.
• G. Stanley Hall used questionnaires and interviews, representing the first scientific study of child development.
• Hall agreed with Darwin that childhood milestones mirrored human species' development.
• Developmentalists should identify average ages at which developmental milestones are reached.
• Norms help learn about species evolution and track individual development.
• Arnold Gesell's research suggested a genetically programmed sequential pattern of change and used maturation describe this.
• Maturationally determined development occurs regardless of practice, training, or effort.
• Gesell pioneered movie cameras to study children's behavior which became the basis for norm-referenced tests to assess individual development.

The Lifespan Perspective

• Psychologists previously viewed adulthood as stable, followed by unstable years before death.
• The lifespan perspective is the idea that important changes occur throughout life.
• Divorce and career shifts are now common occurrences during adulthood.
• There is a significant increase in life expectancy in the industrialized world.
• Understanding adulthood change is important, requiring multidisciplinary input.
• Core elements of the lifespan perspective:
  • Individuals of all ages possess the capacity for positive change in response to environmental demands.
  • Research from different disciplinary perspectives is needed to fully understand lifespan development.
  • Individual development occurs within several interrelated contexts.
• Paul Baltes emphasized the positive aspects of advanced age such as strategies to maximize gains and compensate for losses.

Domains and Periods of Development

• Age-related changes are grouped into physical, cognitive, and social.
• Physical domain is changes in size, shape, and body characteristics.
• Cognitive domain is thinking, memory, problem-solving, and intellectual skills.
• Social domain is variables associated with relationships to others.

Periods of Development

• Prenatal period has clear biological boundaries: conception to birth
• Infancy begins at birth and ends when children begin to use language to communicate.
• Cultures vary on when early childhood ends and middle childhood begins.
• Puberty signals the end of middle childhood and the start of adolescence.
• Early adulthood begins after the end of adolescence.
• There are varying legal boundaries for the end of adolescence and the beginning of early adulthood.
• Such variations highlight social and psychological transitions.
• Emerging adulthood encompasses the late teens and early 20s.
• Defining transitions from early to middle adulthood is arbitrary.
• There is no clear physical/social boundary distinguishing middle age from older adults.
• These periods serve as a system for organizing the study of development.
• The first two years after birth constitute infancy
• Years between 2 and 6 are defined as early childhood
• Between the ages of 6 and 12 is middle childhood
• Adolescence is the years from 12 to 18
• Early adulthood is between those between the ages of 18 and 40
• The period from 40 to 60 is middle adulthood
• The years from 60 to the end of life are late adulthood.

Key Issues in the Study of Human Development

• These issues include relative contributions of biological and environmental factors.
• The presence/absence of stages is also debatable along with the degree context contributes to outcomes.

Nature versus Nurture

• It is the debate is about relative contributions of biological processes and experiential factors to development.
• Early developmentalists focused on forces inside/outside the person but psychologists moved towards more subtle approaches.
• The concept of inborn biases is based on the notion that children are born with certain tendencies for responding.
• Some inborn biases are shared by virtually all children.
• Other inborn biases may vary from one individual to another.
• A baby is not a blank slate at birth and babies prepare to seek out and react to particular experiences.
• Thinking on the nurture side is more complex than in the past.
• Modern developmentalists accepted the concept of internal models of experience.
• This depends on the individual's interpretation.

Continuity versus Discontinuity

• This issue is whether age-related change is primarily amount/degree or type/kind.
• Continuous aspect of friendship is people of all ages have peer relationships
• Discontinuous aspect is the characteristics of friendship vary by age.
• Quantitative change is a change in amount which has continuity from one age to the next.
• Qualitative change is a change in characteristic discontinuous in nature meaning postpubescent humans are qualitatively different.
• Significant to developmental theories, the concept of stages is not needed with only additions.
• The concept of stages may be useful with reorganization or wholly new strategies, qualities, or skills.
• An important difference among the theories of development is whether they assume that development occurs in stages.

Three Kinds of Change

• They are taking your first steps and your first date, but they are fundamentally different.
• Generally developmental scientists think of each age-related change as representing one of three categories.
• Normative age-graded changes are universal and linked to ages
• Social clock defines a sequence of "normal" life experiences in each culture, as well as age norms.
• Age norms can lead to negative prejudicial attitudes against older adults known as ageism.
• Normative history-graded changes occur in most members of a cohort, a group of individuals who were born and share historical experiences
• Nonnormative changes are results from random unshared unique events.
• Genetic differences including physical characteristics as well as genetic disorders represent individual differences
• Characteristics influenced by both heredity and environment, such as intelligence and personality.
• Timing of a developmental event influences individual differences.
• Child-development theorists adopted the concept behind a critical period but in the sensitive period the child may be particularly responsive
• on-time and off-time events

Contexts of Development

• One must consider the relationship of multiple contexts to fully understand human development
• Each child is born with vulnerabilities and protective factors.
• Contexts interact with individual characteristics with culture has no common definition.
• Researchers study why people retire and how it affects health.
• To be aware of retirement-related phenomena does not constitute universal changes.
• The study of gender influences human development
• Atypical Development
• The individual changes that deviate from "normal" are called atypical which could be harmful to that individual, or others.

Research Methods and Designs

• The easiest way to understand research methods is look at a specific question and the alternative ways we might answer it.

The Goals of Developmental Science

• Researchers use the scientific to achieve four goals: describe, explain, predict, and influence human development from conception to death

Descriptive Methods

• Two variables that researchers are interested in: age and memory

Descriptive Methods

• Using observational experiments where psychologist study people in their natural environment is called: naturalistic observation
• The weakness of a naturalistic observation, is it may fall victim to observer bias
• You can avoid this with so called "blind" observers
• You can also use multiple observations to check one observer's accuracy
• The greatest weakness is their degree of generalizations

Descriptive methods: Case Studies

• Doing extremely deep examinations of one individual test's is a Case Study
• An example of a case study would be a deep dive comparing early and late adulthood memory performance
• Are are extremely useful for unusual developmental events, such as brain injuries or strokes

Descriptive Methods: Laboratory Observation

• Differ from naturalistic observations in that they are more controlled, but less natural environments
• Suppose you could test cheating in a controlled environment.

Descriptive Methods: Surveys

• You would be participating in a survey. , a study in which researchers use interviews and/or questionnaires
• A population is the entire group and a sample is the subset
• A representative sample gives a more accurate representation

Correlations

• Correlational Experiments use a number ranging from -1.00 to +1.00, this indicates correlations between the variables.
• A positive Correlations means the high scores accompany high amounts of one another
• A negative correlation means the opposite
• Useful as they are, though, correlations have a major limitation: They do not indicate causal relationships.

The Experimental Method

• An experiment is a study that tests a causal hypothesis.
• A key feature of an experiment is that participants are assigned randomly to one of two or more groups.
• Participants in the experimental group receive treatment, and the control group receives either no special treatment or a neutral treatment.
• The presumed causal element in the experiment is called the independent variable, and it is expected to affect the dependent variable.
• Researchers may use quasi-experiments by comparing members of naturally occurring groups that differ in some dimension of interest.

Designs for Studying Age-Related Changes

• there or three strategies: a cross-sectional design a longitudinal design, and a sequential design.

Cross-Sectional Designs

• Younger adults outperformed those who were older in identifying expression of anger of others in facial expression.
• Influences of this kind lead to cohort effects, findings that result from historical factors to which one age group in a cross-sectional study has been exposed
• Still, cross-sectional research is very useful because it can be done relatively quickly and can reveal possible age differences or age changes.

Longitudinal Designs

• Such studies allow psychologists to look at sequences of change and at individual consistency or inconsistency over time.
• They solve the problems of cross-sectional design because they follow same individuals.
• One issue that the tests get easier over time due to repetition of the experiment
• Some will also drop out
• They do not deal with cohort issues

Sequential designs

• One way of approaching the issue is the approach of sequential design
• Allows better comparison of the data set.
• Age group comparisons

Cross-Cultural Research

• Increasingly are used to study human development, comparing cultures or contexts.
• This may involve comparing different countries.
• For example, comparing the US to Asian countries.
• Two reasons they are useful is because they identify universal changes.

Research Ethics

• Are the study of what the guidelines researchers follow to protect the rights of animals in research

Ethical standards for research

• Protection from harm: it is unethical to do research that is unethical, that could cause long term harm
• Informed consent: Informed consent also be given
• Confidentiality: Participants have the right to confidentiality.
• All individuals have the power to review and summarize results