psyc 160 notes ch 1

Development is plastic, meaning it is flexible and can change based on circumstances. This includes adaptability of individuals, such as those who lose limbs. The human brain exhibits plasticity by adapting and changing with experiences, indicating that learning can reshape our brain functions (Green & Bavelier, 2008). Development is not linear; it can move forward, backward, or sideways at times.

Individual differences are crucial when discussing development; while common patterns help predict developmental pathways, individual variation must also be considered.

Diversity is inherent among humans, entailing both common developmental patterns and individual differences. Sources of diversity include gender, race, ethnicity, socioeconomic status, and sexuality.

Race is a complex concept, difficult to define as it often relies on physical traits, primarily skin color. It is a social rather than a biological category; there is more genetic variation within racial groups than between them (Sussman, 2014). Genomic research indicates that approximately 99.9% of our genetic material is shared across humanity, leading to millions of differences stemming from that minor 0.1% (Bonham et al., 2005). Thus, while genetic differences exist, they typically do not impact appearance or behavior significantly.

The interpretation of race can influence identity development, although it does not determine behavior. Ethnicity is based on a shared identity from common ancestry, traditions, customs, and sometimes nationality, and it differs from culture, which encompasses multiple ethnic groups. Some argue for using ethnicity over race to avoid implying superiority among groups (Markus, 2008).

Lastly, both race and ethnicity are social constructs, shaped by shared ideas and open for interpretation. The impact of these constructs is significant, as they can influence individual behavior and developmental pathways depending on personal and societal perceptions.

Everyday Theories of Development

Everyone has theories about development, such as why some 12-year-olds are aggressive and others are not. These theories often stem from personal observations and societal norms.
Everyday theories are typically not systematic; they may identify environmental factors without explaining why some children from the same background still behave differently.

Scientific Approach to Development

Scientific theories strive to explain development in a clear and structured manner, ensuring that they are testable and free of contradictions.
Good theories lead to testable predictions about behavior. For instance, social learning theory suggests that children are likely to imitate the actions of adults more than their words.
Example: Bryan and Walbek (1970) found that children who observed an adult donating were more likely to donate themselves, affirming the theory's predictions.

The Scientific Method

Identifying a Question: Begin with curiosity about a specific aspect of development (e.g., aggression in children).
Forming a Hypothesis: Develop a testable prediction based on existing knowledge. Hypotheses should stem from theoretical frameworks or prior research.
Testing the Hypothesis: Conduct experiments while clearly defining independent (manipulated) and dependent (measured) variables. It's crucial to establish operational definitions.
Replication: Validate results through repeated studies to see if findings are consistent across different populations and contexts.
Dissemination: Publish findings in scientific journals to share knowledge with the research community and inform future studies.

Research Methods

Scientific Experiments

Experiments establish causation and are the gold standard for studying development. They involve manipulation of independent variables to observe effects on dependent variables.
Control groups are essential; they do not experience the manipulation, providing a baseline for comparison.
For example, in a study on cheating, one group may be asked to promise not to cheat (experimental group), while another group is not (control group).

Correlations

Correlational studies assess the relationship between two variables without implying causation. These studies produce correlation coefficients ranging from -1 to +1.
A positive correlation indicates that as one variable increases, the other does as well, while a negative correlation indicates an inverse relationship.
Example: A correlation exists between the number of storks and the number of babies, but this does not imply that storks cause births—this serves as an example of a spurious correlation.

Surveys

Surveys involve collecting data from a large sample of people through questions. They help identify patterns but cannot establish cause-and-effect relationships.
The representativeness of the sample is crucial, as biased responses can skew results. Self-selection bias can affect who chooses to participate in surveys.
Surveys can be conducted in diverse formats: online, written, or face-to-face, each of which can impact participation rates.

Observations

Observations can be naturalistic (unobtrusive) or structured (controlled) and are essential for understanding behaviors in context.
This method was historically used by figures like Charles Darwin and Jean Piaget to study emotional expressions and cognitive development.
Scientific observation involves systematic documentation of behaviors, enhancing objectivity and reproducibility but does not establish causation on its own.

Measuring Change Over Time

Cross-Sectional Studies: Compare different groups of varying ages at a single point in time (e.g., a group of 25-year-olds vs. a group of 65-year-olds). These studies are efficient but cannot account for historical differences affecting results.
Longitudinal Studies: Track the same individuals over time, assessing changes as they age. This method is valuable but can face challenges with participant dropout and the influence of historical events.
Cross-Sequential Studies: Combine elements of both cross-sectional and longitudinal studies by assessing multiple age groups over time. This design helps differentiate the effects of aging from cohort effects, providing richer insights into developmental changes.

Evaluating Evidence

When encountering claims about development, critically analyze the source (e.g., academic articles vs. social media) and its credibility (e.g., publication by a legitimate research institution).
Investigate the research methods employed, whether rigorous techniques were used, and if the study acknowledges its limitations or potential biases.
Be wary of overly simplified statements or broad generalizations about development; keep in mind that correlation does not equal causation and results may vary widely depending on context or methodology.

All researchers must consider questions of ethics. Ethics relates to how our research can be conducted without causing harm to its participants. In lifespan human development and other areas of psychology, particular attention must be paid to protecting research participants, as the subject matter of psychology has the potential to disturb participants. To guide researchers, professional associations have drafted codes of ethics to which their members must abide. In addition, universities and research institutions require that all research projects first receive ethical approval from institutional review boards.

An overview of the ethical codes of two organizations, the American Psychological Association and the Society for Research in Child Development, highlights the main ethical principles to be considered in developmental research:

Do No Harm: The first principle is to do no harm. Psychologists should take every effort to ensure that participants are not distressed by their participation. In cases where participation may lead to discomfort (e.g., finding an intelligence test difficult might make people feel bad about their abilities), debriefing should occur to help participants cope. Psychologists can trigger temporary discomfort (e.g., frustration from a hard puzzle), but the discomfort must be low level and temporary.
Informed Consent: Participants must be asked for their consent to participate in research. Consent must be informed, meaning participants should be told what is involved and that they can withdraw at any time. Some deception is allowed if it does not affect results significantly. In studies involving children, both the consent of a parent/guardian and the child's understanding and willingness to participate are critical. Researchers need to monitor children's body language and allow them to withdraw if they seem uneasy.
Confidentiality: The identity of participants must be kept confidential, and records should be stored confidentially. Reporting results should avoid identifying informants, such as by not naming the towns or schools participants come from.

Additionally, researchers must consider the intended use of their research. They have a responsibility to ensure that their results are utilized ethically. Furthermore, they should strive to recruit diverse participants, as most samples in psychological studies often represent a narrow demographic (e.g., White, middle-class, young adults). Ethical questions in research are ongoing, and researchers must continuously reflect on their practices to ensure ethical behavior.