Chapter 1 Understanding Life-Span Human Development

Three broad domains What is Development? Development Cognitive Physical Cognitive Psychosocial Development

Other Developmental Definitions Maturation: (nature) The biological unfolding of the individual genetic plan Learning: (nurture) Relatively permanent changes due to environmental experiences Development is due to interplay between nature and nurture

Age Grade: Socially defined age groups Statuses, roles, privileges, responsibilities Age Norms: Behavioral expectations by age Social Clock: When things should be done “Off time” vs. “On time” experiences

Figure 1.1 Aggression among children in four cultures.

Goals of Studying Life-Span Development Description Normal development, individual differences Explanation Typical and individually different development Optimization Positive development, enhancing human capacities Prevention and overcoming difficulties

MODERN LIFE-SPAN PERSPECTIVE Development is A lifelong process Involves both gain and loss Characterized by lifelong plasticity Shaped by its historical-cultural context Multiply influenced

The Scientific Research Approach The scientific research approach is objective, systematic, and testable STEP 4 Revise Research Conclusions & Theory STEP 3 Draw Conclusions & create theory STEP 2 Collect Information Please Note: The content of this slide is not in the text. If you do not wish to use it in a presentation, you may either delete or hide it. STEP 1 Conceptualize the Problem

Figure 1.2 The Scientific Method in Action

Description Naturalistic Observation: Observing subjects in natural environments Researcher Jane Goodall studies the behavior of wild chimpanzees in their native habitat.

Descriptive Methods Laboratory Observation: Observing subjects in artificially controlled environments In this experiment, preschoolers’ reactions to the puppet are monitored.

Description Case Study Phineas Gage Is language uniquely human?

Survey A technique for ascertaining the self-reported attitudes, opinions or behaviors of people OBJECTIVE 3-2| Identify the advantages and disadvantages of surveys in studying behavior and mental processes, and explain the importance of wording effects and random sampling. http://www.lynnefeatherstone.org Psychology 7e in Modules

Unrepresentative sample Population Sampling procedure Representative sample

Survey Population – all the cases in a group Random Sampling if each member has an equal chance of inclusion into a sample, we call that a random sample (unbiased). The fastest way to know about the marble color ratio is to blindly transfer a few into a smaller jar and count them.

Random Sampling from Population LO 1.9 Case studies and surveys Random Sampling from Population INFERENCE POPULATION SAMPLE

Descriptive Methods Laboratory observation – Naturalistic and laboratory settings Descriptive Methods Laboratory observation – watching animals or humans behave in a laboratory setting.

(positive or negative) Correlation When one trait or behavior accompanies another, we say the two correlate. Indicates strength of relationship (0.00 to 1.00) Correlation coefficient r = + 0.37 OBJECTIVE 3-4| Describe positive and negative correlations and explain how correlational measures can aid the process of prediction. Correlation Coefficient is a statistical measure of relationship between two variables. Indicates direction of relationship (positive or negative) Psychology 7e in Modules

Finding Relationships Correlation coefficient ranges from 0 to 1.00 Closer to 1.00, the stronger the relationship between the variables. Positive correlation – variables are related in the same direction. Negative correlation – variables are related in opposite CORRELATION DOES NOT PROVE CAUSATION!!!

Figure 1.7  Correlation Correlation, a research method used for prediction, shows how two variables are related.

LO 1.10 Correlational technique Menu

Correlation and Causation OBJECTIVE 3-5| Explain why correlational research fails to provide evidence of cause-effect relationships. Psychology 7e in Modules

Correlation does NOT prove causation LO 1.10 Correlational technique Correlation does NOT prove causation Menu

Correlation Coefficient Interpretation Range Strength of Relationship 0.00 - 0.20 Very Low 0.20 - 0.40 Low 0.40 - 0.60 Moderate 0.60 - 0.80 High Moderate 0.80 - 0.90 High 0.90 - 1.00 Very High

Figure 1.3 Plots of hypothetical correlations between the amount of TV children watch and the number of aggressive acts they display. Each dot represents a specific child who watches a high, medium, or low amount of TV and commits a high, medium, or low number of aggressive acts. Part A shows a positive correlation between television watching and aggression: The more TV a child watches the more aggressive he or she is. Part B shows a negative correlation: The more TV a child watches, the less aggressive he or she is. Finally, Part C shows a zero correlation: Amount of TV watched is unrelated to amount of aggression displayed. Figure 1.3

Height and Temperament of 20 Men Correlation Height and Temperament of 20 Men 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 80 63 61 79 74 69 62 75 77 60 64 76 71 66 73 70 68 90 42 81 39 48 72 57 30 84 Subject Height in Inches Temperament

Scatterplot of Height and Temperament Correlation 95 90 85 80 75 70 65 60 55 50 45 40 35 30 25 Temperament scores Height in inches 55 60 65 70 75 80 85 Scatterplot of Height and Temperament

The Experiment Operational definition - definition of a variable of interest that allows it to be directly measured. Independent variable (IV) - variable in an experiment that is manipulated by the experimenter. Dependent variable (DV) - variable in an experiment that represents the measurable response or behavior of the subjects in the experiment. Definition: Hitting while playing IV: Violent TV DV: Aggressive play

Concept Check Operational definitions Which of the following might be used as an operational definition of “attraction”? A feeling of affection when two people are together. (1) The number of minutes during which two people are touching each other over a four-hour period. (2)

Concept Check Which of the following might be used as an operational definition of “assertiveness?” The number of times a person makes requests or states his or her feelings over the course of a one-hour interaction. (1) An appearance of confidence and ease in social situations. (2)

Evaluating Therapies Random Assignment Assigning participants to experimental (Breast-fed) and control (formula-fed) conditions by random assignment minimizes pre-existing differences between the two groups. Sometime research participants out of enthusiasm or personal beliefs can affect the out come of an experiment. To control for such affects, a double-blind procedure is used, in which the participants and the experimenter’s assistants are not aware of which participants got real treatment and who got placebo. Psychology 7e in Modules

Random Assignment LO 1.11 Experimental approach and terms Experimental Group Test for Differences SAMPLE Control Group Menu Psychology 7e in Modules

Confounding Variables LO 1.11 Experimental approach and terms Effect of violent tv on aggression Experimental Group SAMPLE Are differences due to manipulation or confounding variable (mood)? Control Group Menu Psychology 7e in Modules

No Confounding Variables LO 1.11 Experimental approach and terms Effect of violent tv on aggression Experimental Group SAMPLE Differences due to manipulation, not an extraneous variable because mood randomly determined. Control Group Menu Psychology 7e in Modules

Scientifically compare performance of the two groups Experimental Method Experimental group (noise condition) Measure amount of learning Scientifically compare performance of the two groups Sample of participants Control group (no-noise condition) Measure amount of learning The logic of designing an experiment. The experimenter manipulates the amount of noise to which participants are exposed, measures their learning, and attempts to treat them equally in every other way. This creates an experiment group and a control group.

Figure 1.9  Elements of an Experiment The two main ingredients of an experiment are (1) that the variables in the study are controlled or manipulated and (2) that participants are randomly assigned to the conditions of the study. When these two conditions have been met, causal conclusions may be drawn.

Claim: If kids eat large amounts of sugar, they become hyperactive. Problem: How would you test the claim that sugar makes children hyperactive? 39 Copyright © Allyn and Bacon 2009

What is the relationship between sugar and behavior? 40

A summary of steps during experimentation.

Below is a comparison of different research methods.

Concept Check A researcher wants to know if a particular herbal supplement is helpful for improving memory. She selects 100 college sophomores who achieved an average score on a memory test, gives half of them the herb for one month, half of them an inert pill, and the re-tests them all.

The Scientific Method An example of a claim that is NOT falsifiable: The telephone psychic says “Next year, you will go through a big change.” This is not falsifiable because it is too vague.

The Scientific Method An example of a claim that is NOT parsimonious: The sun goes around the earth. Little gnomes push it around the sky every day. We can’t see them because they are invisible to the human eye. This is not parsimonious because too many assumptions must be made in order for the claim to be accepted as fact.

Concept Check Is this claim falsifiable? “You will encounter new challenges in your travels this week.”

Concept Check “An oversupply of dopamine in the human central nervous system will eventually result in a decline in the number of receptors available for that neurotransmitter.”

Concept Check “On March 19th, 2006, you will meet a 30-year-old millionaire who will offer you an exciting entry-level job in a growing high-tech company in Austin, TX.”

Concept Check “Children whose parents divorce will eventually have serious emotional and relationship problems.”

Developmental Research Designs Cross-Sectional Designs +1 cohorts (same generation) or age-groups studied 1 time of testing Studying age differences at any one time Longitudinal Designs 1 cohort (same generation) +1 time of testing Study changes across time in one cohort

Figure 1.4 Cross-sectional and longitudinal studies of development from age 30 to age 70.

Age, Cohort, and Time of Measurement Effects Age effects: Changes which occur due to age Cohort Effects: Born in one historical context Changes due to differences in society Disadvantage of cross-sectional design Time of measurement effects: Historical Take place at time of data collection Disadvantage of longitudinal design

Sequential Designs A combination of cross-sectional and longitudinal designs Advantages of both designs Gives information about Which age-related trends are age effects? Which age-related trends are truly cohort effects? Which age-related trends are a result of historical events?

Figure 1.6 A sequential research design combines the cross-sectional and longitudinal approaches. Here, we start with a cross-sectional study in 1980 and reassess the same people every 10 years. Figure 1.6

Protecting the Rights of Participants Risk to benefit balance of the research Researcher responsibilities Informed consent Debriefing Protection from harm Confidentiality