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Levels of Analysis ( LoA ). Biological Cognitive Sociocultural. Biological LoA. Focuses on physiology and genetics Gender differences via genetic makeup XY and XX chromosomes Gender differences from the impact of hormones testosterone and estrogen. Cognitive LoA.
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Levels of Analysis (LoA) Biological Cognitive Sociocultural
Biological LoA • Focuses on physiology and genetics • Gender differences via genetic makeup • XY and XX chromosomes • Gender differences from the impact of hormones • testosterone and estrogen
Cognitive LoA • Focuses on mental processes • Memory • Thinking • Perception • Attention • Gender differences via gender schema theory • Social cognition • Gender stereotypes
SocioculturalLoA • Focuses on how environment and culture impact behavior and thinking • Impact of cultural definitions and roles for our mental representations of each gender • Gender differences explained through social learning theory • Watching individuals of the same sex for behavior cues
Biological Level of Analysis physiology and genetics
Biological LoA: Physiology & Behavior • Biology can affect cognition and cognition can affect biology…relationship is bidirectional • Physiological factors that impact behavior: • Brain processes • Neurotransmitters • Hormones • Genes • Physiology does not work alone since environmental stimuli influence our behavior • Stressful experiences • Attractive person passing by • Brain damage caused by trauma
Goal of IB Psychology Taking a holistic approach to human behavior Interactionist Approach: Both sides of nature (biology) vs. nurture (environment) argument.
Principles of Human Behavior (Biological LoA) • Behavior can be innate since it is genetically based Evolution…key role in behavior • Animal research can provide insight to human behavior Much research done with animals • Biology correlates with behavior Links between specific biological factors and specific behaviors
Reductionist Approach Micro-level research; breaking down complex human behavior into simple parts. Criticized for being over simplistic but allows us to gain detailed knowledge of human behavior Important because it allows understanding of several factors that influence one behavior
The Endocrine System Glands that produce hormones in the body Enter from glands to bloodstream (longer) i.e. pituitary, adrenal, testes, ovaries, etc.
Oxytocin, the “Love Hormone” Produced by hypothalamus Firing of neurons by amygdala From stimulation by pituitary gland, hugs, and touches Plays role in inducing labor, trust, generosity, and attachment to others
Melatonin, the “Sleep Hormone” Made by pineal gland An unbalance of melatonin gives symptoms of insomnia and/or jet lag Increase during night/darkness, vice-versa Release correlates with circadian rhythm
Seasonal Affective Disorder (SAD) Side effect of excess melatonin Found by Rosenthal in 1987 Subcategory of depression Sleepiness, lethargy, carbohydrates craving and apathy Cure is sunlight AKA go outside more
Impact of Neurotransmitters on Behavior • Influences mood, memory, sexual arousal, and mental illness • Acetylcholine • Muscle contraction, helps with development of memory in hippocampus • Dopamine • Voluntary movement, learning, feelings of pleasure • Norepinephrine (noradrenalin) • Arousal, alertness, stimulation of sympathetic nervous system • Serotonin • Sleep, arousal levels, emotion
Affect of Serotonin on Behavior Tokyo University (Kasamatsu and Hirai, 1999) Aim: How sensory deprivation affects the brain Buddhist monks deprived of food, water, no communication, and exposure to cold weather 48 hours, hallucinations Blood samples before and right after hallucinations (serotonin levels increased which activated the frontal cortex and hypothalamus) Conclusion: Sensory deprivation released serotonin which altered monks experience.
Drugs Stimulate the production of neurotransmitters Block receptor sites if too much is produced Mouse Party Simulation: http://learn.genetics.utah.edu/content/addiction/mouse/
Technology and the Brain & Behavior • Technology gives researchers the ability to monitor and discover the “map” of the brain’s activity • Previously, case studies were used; usually situations that would be unethical to reproduce in the lab. • Case studies of brain damaged patients carried out over a long period of time (longitudinally) • Phineas Gage, Paul Broca, Carl Wernicke • Allows for observation of short-term and long-term effects
Localization of Brain Function The idea that specific parts of the brain are responsible for specific functions When a behavior is localized in the brain, it is possible to trace the origin of the behavior to a specific part of the brain. Does not explain ALL human behavior but is a major step forward in brain research
Research on the role of the nucleus accumbens (pleasure center) Robert Heath (1950s) James Old (1950s) Electrically stimulated parts o f the brain in depressed patients=experienced pleasure One patient (B-19) electrically stimulated himself 1,500 times in 3 hours Experienced euphoria and elation and was eventually disconnected against his will Rats would receive electrical stimulation to the nucleus accumbens when a lever was pressed Crossed over electrified grids and preferred pleasure lever over food and water
Brain Functions and Ethical Considerations • Electrical stimulation of the nucleus accumbens is based mainly on dopamine (desire) and serotonin (satiety and inhibition) • Via animal studies, all drugs increase the production of dopamine in the nucleus accumbens and reduce serotonin. • Cocaine and nicotine • Frequent use of drugs increase the amount of dopamine in the nucleus accumbens. • Why drug addicts have an obsessive drive to seek more drugs even though they know its not good for them
Spiders on Drugs http://www.trinity.edu/jdunn/spiderdrugs.htm
Technology vs. Invasive Techniques Technology Invasive Techniques • Study the active brain • EEG, PET, fMRI • More ethical • May be misleading • Ablation (removing) & leisoning (scarring) techniques on animals • Harm cannot be reversed • Ethical? • Pain?
Research Researchers use a lot of technology to study the localization functions of the brain. Option to study active brain See where specific brain processes take place
Invasive Techniques The more invasive techniques that scientist use to study the brain are reserved for animals such as rats They benefit us because we are to complete ablations which is where a piece of the brain is removed in order to examine the differences in behavior.
Invasive Technique Hetherington and Ranson - Lesion part of the brain called ventromedial hypothalamus in rats ~ Increased food intake dramatically & doubled weight ~ Hypothalamus acts as a brake on food intake
Ethics Raise serious ethical concerns Modern Researchers use EEG (electroencephalogram) Thought of as Brain Waves Transports information through electrical change EFG registers patterns of voltage change in the brain
Position Emissions Topography (PET) Scan Monitors glucose metabolism in the brain Patient is injected with a harmless dose of radioactive glucose and the radioactive particles emitted by the glucose are detected by the PET scanner Produces color maps of brain activity Diagnoses abnormalities
Functional magnetic Resonance imaging (fMRI) Provides 3D pictures of brain structures using magnetic fields and radio waves. Shows actual brain activity and indicated which areas of the brain are active. ~Have higher resolution than PET scans ~ Most frequently used technologies in biopsychological research today.
Then and Now • Then (1960’s) -Thought that brain was influenced only by genetics • Thought to be unchangeable • Hubel & Weisel (1965) • Showed that brain changes as response to environmental input • Were based on rats • Now • Generally accepted that environment enrichment can modify brain, especially in cerebral cortex (area of higher cognitive function) • Brain is constantly changing as result of experience throughout lifespan
Brain Plasticity • Refers to brain’s ability to rearrange the connections between its neurons • Changes that occur in the structure of brain as result of learning/experience • Adapts to challenges of the environment • Can change functional qualities of various brain structures depending on regularity and type of new tasks that neurons are asked to perform • Neural connection density affected by high level stimulation and learning opportunity at appropriate times
Brain Plasticity (cont.) • Dendritic Branching • The dendrites of the neurons grow in numbers and connect with other neurons
Rosenzweig and Bonnett (1972) • Studied brain plasticity with rats • To measure the effect of either enrichment or deprivation on the development of neurons in the cerebral cortex • Used interesting tags to play with (stimulating) and no tags (deprived environment) • Last 30-60 days then were sacrificed • Stimulated environment rats had increased thickness in the cortex • Frontal lobe, associated with thinking, planning, and decision making, was heavier in rats that were in stimulated environment
Rosenzweig and Bonnet (1975) (cont.) • Similar studies show if the rats had more rats with them, the cortex would then be thicker • Company + toys=best conditions for cerebral thickness • These findings can be generalized to humans to some extent • Humans brains differ in genetic make-up and environment inputs • Makes it difficult to decide what is considered to be an enriched environment • Raises questions of the importance of education in growth of new synapses • If it works as though, environmental stimulation is important for human cortex
Mozart Effect (Rauscher et al. 1993) One of the most well-known claims of brain plasticity Listening to Mozart temporarily increases spatial reasoning ability Structurally complex musical compositions excites brain firing pattern as when physically completing spatial tasks
Mozart Effect (Rauscher et al. 1993) • Research shows that it has nothing to do with Mozart but with arousal • May just be increase in sense of attention • Thompson et al. (2001) if mood elevates -> improved spatial skills but if mood doesn’t elevate -> no improvement (all in result of music) • This idea suffers from problems with ecological validity • Doesn’t show behavior in a real-life situation
Videos about Brain Plasticity http://www.youtube.com/watch?v=VaDlLD97CLM (Ben Carson) http://www.youtube.com/watch?v=2MKNsI5CWoU (Cameron: Today Show)
Richard Davidson In 2004 he held an experiment with eight Buddhist monks. They were highly experienced with meditation, and the ten volunteers that were there were trained in meditation for one week. The participants were told to meditate on love and compassion.
The experiment He used a PET scan to observe that two of the controls and all of the monks experienced an increase in brain waves during meditation. As soon as they were done meditating, the gamma waves returned to normal. The monks were more experienced so their gamma waves had no difference. The spot where the gamma waves were found in the monks brains during meditation on love and compassion was found to be larger than the other volunteers brains.
Conclusion Davidson argued that meditation could have long term effect on the brain and the way it processes emotions. The brain adapts to stimulation (either from environment or our own thinking)
Mirror Neurons One of the ways that people learn is by observing others and then imitating their behavior. Mirror Neurons – Neurons that fire when an animal (or person) performs an action or the animal/human is observing an action being performed
Mirror Neurons (CONT.) • Mirror Neurons play a vital role in the ability to learn from – as well as empathize with – another person. • Example: At a football game or sporting event, when a player gets hit hard, the crowd cringes and reacts as if they were the one who had been hit.
Gallese et. al. (1996) Researchers at the University of Parma in Italy, accidentally discovered mirror neurons. Because neural messages are electrical in nature, the researchers would hear a telltale crackling sound whenever the neurons were activated in the monkeys. Every time a monkey would reach for a peanut, the crackling sound was heard, not from just the monkey performing the action, but from the other monkeys as well.
Biological LoA: Genetics & Behavior • Behavioral genetics: Understanding how both genetics and the environment play a role to individual variations in human behavior. • Rhesus macaque monkeys & humans • 93% genes are shared, the 7% makes a large difference • Complexity of genetics: • Inheritance contributes to behavior and acts as a building block however, it is not probable that one specific gene is responsible for complex behaviors: • Intelligence, criminal behavior, attachment, altruism
+ = DISORDER Stress (environment) Biological / genetic predisposition The diathesis-stress model The model looks at the genetic/biologic vulnerability to a disorder/disease and the stress or traumatic environmental stimuli that may trigger a disorder (such as depression) The diathesis-stress model uses the analogy of a "walking time bomb" to help explain why, for example, not 100% of identical twins both get depression. It also helps to explain why a large percent of people in traumatic situations (post 9/11, rape, etc.) never develop PTSD. The model further talks about a balance -- the greater the diathesis or predisposition, the less the stress required for the disorder to "appear" and visa versa.
Last year’s notes on genetics and evolution… I hope you didn’t lose them! If you did, in your hours of free time, check these out on the wiki
Inheritance • Genes that are passed down from parents to their off-spring • Humans are composed of 24 pairs of chromosomes • 20,000-25,000 genes • James Watson: Human Genome Project • 1990-2003 • Mapped human genes • Regardless of this amazing accomplishment, the role of specific genes are still unknown
Genetic Research • Based off of correlation studies • Independent variable is not manipulated, so no cause and effect can be determined. • Three types: • Twin Studies • Family Studies • Adoption Studies
Monozygotic (MZ) Dizygotic (DZ) Twin Studies Used as basis for hypotheses since they show the different degrees of genetic relationship. In twin studies the correlation found is known as concordance. • Identical: one egg split in two • Share 100% of genes • Same sex • Fraternal: Formed from two separate eggs • Share 50% of genes just like any other siblings • Same or different sex