Psychology 304: Brain and Behaviour Lecture 1 1 Introductory Concepts and Research Methods 1. What is biological psychology? 2. What is the relation between biological psychology and other disciplines of neuroscience? 3. What types of research methods do biological psychologists use? 2 By the end of today’s class, you should be able to: 1. define the term “biological psychology.” 2. describe neuroscientific disciplines related to biological psychology. 3. describe the scientific method. 4. distinguish between the distinct types of studies used in biopsychological research. 3 What is biological psychology? • A branch of neuroscience. • The scientific study of the biological bases of psychological processes and behaviour. • Also referred to as biopsychology, behavioural neuroscience, cognitive neuroscience, psychobiology, and behavioural biology. 4 What is the relation between biological psychology and other disciplines of neuroscience? • Biological psychology draws upon research findings from many other disciplines of neuroscience. Among these are: Neuroanatomy Neuroendocrinology Neurophysiology Neuropathology Neurochemistry Neuropharmacology 5 What types of research methods do biological psychologists use? • Biological psychology relies upon the scientific method— that is, systematic and objective observation. • Several steps are involved in conducting research using the scientific method: 6 Theory Hypothesis Operationalization Interactive Relationship Research Data 7 • Biopsychological research involves four types of studies. 1. Experimental studies Designed to examine cause and effect relationships between variables. 8 In conducting an experiment, a researcher: (a) randomly assigns subjects to groups that will receive different levels of the hypothesized “causal” or independent variable (IV). (b) administers a distinct treatment (i.e., level of the IV) to each group. (c) measures the hypothesized “effect” or dependent variable (DV) for each group. 9 A Simple Experiment Group A Subjects Treatment A Posttest Random Assignment Group B Treatment B Posttest 10 Example: Lester and Gorzalka (1988). Randomly assigned female rats to one of two treatment groups: Treatment Group A: Copulated with one male, then with a second male, and then with the original male again (i.e., 1, 2, 1). Treatment Group B: Copulated with one male, then with a second male, and then with a third male (i.e., 1, 2, 3). 11 Results: Treatment Group A Mean Lordosis Duration (Minutes) 35 Treatment Group B 35 30 30 25 25 20 20 15 15 10 10 5 5 0 0 1st Qtr Male 1 Male 2 1st Qtr Male 1 Male 1 Male 2 Male 3 12 Conclusion: Females who lose sexual interest in males that they have previously copulated with will display renewed sexual interest when presented with a novel male. This effect is referred to as the “Coolidge effect.” 13 2. Quasi-experimental studies Designed to contrast two or more existing groups on a variable of interest. Used when an experiment cannot be conducted due to ethical or practical limitations. Subjects are not randomly assigned to groups. As a result, causal conclusions cannot be drawn. 14 Example: Acker, Ron, Lishman, & Shaw (1984). Contrasted detoxified male alcoholics to non-drinking males. Found that the alcoholic sample: (a) performed relatively poorly on measures of perceptual, motor, and cognitive ability, and (b) had brain damage, as revealed by brain scans. Possible confounds: Education level, number of head injuries, drug use, diet. 15 3. Correlational studies Designed to examine the extent to which 2 naturallyoccurring variables covary. Correlations are typically measured by the Pearson product-moment correlation coefficient (r): Magnitude of r: strength of linear relationship between variables. Sign of r (+ vs. -): direction of linear relationship between variables. 16 Example: Morris, Udry, Khan-Dawood, and Dawood (1997). Examined the correlation between testosterone levels among midcycle women and frequency of sexual intercourse. Found a correlation of .62 (p<.01), indicating that higher midcycle testosterone levels are associated with greater frequency of sexual intercourse. 17 Introductory Concepts and Research Methods 1. What is biological psychology? 2. What is the relation between biological psychology and other disciplines of neuroscience? 3. What types of research methods do biological psychologists use? 18