Psych 202 1st Edition Lecture 7-Research Methods NotesoCan correlations support causal statements?-Third problem variableoThe monoamine deficiency theory of depression states:-Dopamine: DA-Norepinephrine: NE-Serotonin: 5-HT-Depression is caused by low levels of NT's-especially: NE and 5-HT-High level of NE and 5-HT metabolites = lower depressionoDirectionality problem:-Direction 1 (favored by drug companies): the drug causes a chemical change-Direction 2: depression creates the biochemical changeoThird Variable problem: -Activity level-Lack of sleep-EnvironmentLevels of stress-Family problems-Confounding variables-"Do hospital's make people die" example-Activity level is associated with depression and biogenic amine metabolite levels-Observed correlations are said to be spurious when compelling confounding 3rd variables can be identifiedoHow can descriptive correlational data help scientific knowledge development?-Reality: most knowledge begins with noticing correlational associations (David Hume)-Multivariate correlational research: Has same problems of interpretation-Theory development, hypothesis testing, and experimentationoExperimental methods: our best known method for inferring valid causal relationships-Core features:Independent variables (IV's)Dependent variables (DV's)Random sampling from representative populations-Almost never happensRandom assignment to conditions or treatmentsEfforts to "control" extraneous/irrelevant factors-Ex. 1: what affects sexual desirability?-IV: shirt color-Method/procedure:These notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.-What 2 operationalized DV's were identified?-What construct was being tested?-Do color of clothes matter to passion?-What can be concluded, really?-College men who look at pictures of attractive women are more attracted to one in red shirt-Ex. 2: antidepressants vs placebos vs cognitive therapy as treatments for major depression-The sample: depressed people-IV: 3 levels of treatment-Antidepressant-Placebo-Cognitive therapy-Method/procedure:-DV: depression level after 3 months-Results: 60% of antidepressant users and cognitive therapy were no longer depressed, 30% of people who had placebo were not depressed-What can be concluded, really?-The 2 active treatments are better than placebo at reducing depression for people who volunteered to be in this experiment, we don’t know if it applies to everyone-Is there a control group missing?-People who aren't getting any medicine at all-Ex. 3: the seating experiment-Where did the research hypothesis come from?-Physics professor had a theory-Who were the research participants?-What construct was being investigated?-Is there a relationship between where people sitin room and how well they do in course?-IV: seating spot-Method of seating assignment:-Randomly assigned to seat in 1 of 4 groups-Most important DV's:-Grades-Attendance-Fraction of A's decreased steadily as the group's original seat location was furthered from the front while fraction of F's increased-Davidson et al's experiment on Mindfulness and Brain Function (MBSR)-Sample and context: volunteers from a high tech company-upper middle class people who said they wanted to do it, 8 weeks-"Big idea", the abstract construct being tested?-Does mindfulness affect health outcomes?-IV: meditation level-DV's:-Decrease in self-reported negative affect and anxiety-Increase in L-sided pre-frontal cortical symmetry-Left side is happy side-Increase in influenza vaccine antibody titers-Control group: same workgroup but were told they would be on wait list-Confound: unexamined variable that might alter results-In this experiment: MBSR had to work and control group also had to work (jealous of other group)-Correlation relates to important insights but not