Intro to Psychology Exam 1
Chapter 2: Research Methodology
Chapter 3: Biology and Behavior
How Is the Scientific Method Used in Psychological Research?
Data – the measurable outcomes of research studies
The four primary goals of science are:
1. Description – describe what a phenomenon is
2. Prediction – predict when it will occur
3. Control – control what causes it to occur
4. Explanation – explain why it occurs
Critical thinking – systematically questioning and evaluating information using wellsupported evidence
∙ This is considered an ability, not a skill
∙ First, question information
∙ Second, ask for the definition of each part of the claim (evaluation of information)
Peer review – scientists with similar expertise evaluate and critique research reports before publication, ensures that public reports are well designed, conducted in an ethical manner, and address an important question
Don't forget about the age old question of anne pilkington notre dame
Scientific method – an interaction among research, theories, and hypotheses
1. Form a hypothesis
2. Conduct a literature review
3. Design a study
4. Conduct the study
5. Analyze the data
6. Report the results
Theory – an explanation or model of how a phenomenon works, used to explain prior observations and to make predictions based on future events
Hypothesis – a specific, testable prediction, narrower than the theory it is based on
A key feature of a good theory is that it is falsifiable, and produces a wide variety of testable hypotheses. They tend to be more simplistic. They are continually refined and rewritten by new hypotheses and tested by new research methods. Don't forget about the age old question of hes 101
Replication – involves repeating a study and getting the same, or similar results
Serendipity – unexpectedly finding things that are important, which is how many significant findings are discovered
What Types of Studies Are Used in Psychological Research?
There are three main types of research methods:
1. Descriptive – involves observing behavior to describe that behavior objectively and systematically
1.1. Case studies – intensive examination of an unusual person or organization 1.2. Observational studies – includes participant observation where the researcher is involved in the situation, and naturalistic observation, where the observer is passive, separated from a situation and making no attempt to change or alter ongoing behavior 1.3. Coding – involves the systematic assessment and coding of overt behavior 1.4. Reactivity – phenomenon that occurs when knowledge that one is being observed alters the behavior being observed If you want to learn more check out psyc 311 textbook notes
If you want to learn more check out math 1350 ohio university
1.5. Observer bias – systematic errors in observation that occur because of an observer’s expectations
1.6. Experimenter expectancy effect – actual change in behavior being observed due to the expectations of the observer
1.7. Selfreports and interviews – can be used to gather data from a large number of people, like in surveys or questionnaires
2. Correlational – examine how variables are naturally related in the real world, used to describe and predict relationships
2.1. Direction of correlation – correlations can either be positive, where both variables increase or decrease together, or negative, where when one variable decreases and the other increases We also discuss several other topics like sahithya reddivari
2.2. Directionality problem – when researchers find a relationship between two variables, but cannot determine which variable caused changes in the other variable
2.3. Third variable problem – occurs when researchers cannot directly manipulate variables, so they cannot be confident that there is not another variable contributing 3. Experimental – a researcher manipulates one variable to measure the effect on the second variable
3.1. Manipulating variables – in an experiment, the independent variable, the variable that is manipulated, is manipulated while the dependent variable is the variable that is getting measured. If you want to learn more check out phys 220 purdue
Operational definition – a definition that quantifies (describes) and qualifies (measures) a variable so that it can be understood objectively
Experimental group – the participants in an experiment who receive the treatment
Control group – the participants in an experiment who receive no intervention or who receive an intervention that is unrelated to the independent variable being investigated
Cofound – anything that affects a dependent variable and that may unintentionally vary between the experimental conditions of a study
For any research method, psychologists typically want to know their findings are generalizable, meaning they fit for people outside the individuals in the study. To do so, they greatly diversify their population, or the group the experimenter is interested in. However, they only study a subset from it, known as the sample.
Random sample – taken at random from the population
Convenience sample – taken from an available subgroup of the population. Most of the time, circumstances for researchers to use a convenience sample
Random assignment – Participants are assigned at random to the control or experimental group, used when an experimenter wants to test a casual hypothesis
Selection bias – in an experiment, unintended differences between the participants in different groups; could be caused by nonrandom assignment to groups
A researcher has to take into account how well results generalize across cultures. Culture plays a significant role in how people think, feel, and act.
What Are the Ethics Governing Psychological Research?
There are limits to how researchers can manipulate what we do in studies. For ethical and practical reasons, researchers cannot always use the experimental method.
International Review Boards (IRB’s) – guardians of the guidelines, which are shared by all places where research is conducted to ensure the health and wellbeing of all study participants
Another aspect of ethical concern is privacy. Personal, identifying, information about participants cannot be shared with others. Also, researchers must always maintain aware of what they are asking participants.
Risk/Benefit ratio – an analysis of whether the research is important enough to warrant placing participants at risk
Research involving human participation always requires informed consent, meaning the participants make a knowledgeable decision to participate, usually in written form. Researchers must also consider who will have access to the data collected, so that confidentiality can be kept.
When research is done with animals, the health, wellbeing, and the fairness of treatment must always be considered.
How Are Data Analyzed and Evaluated?
If you collect data to answer a research question, the data must be valid, meaning the data must accurately measure the concepts that you think they measure, accurately represent a phenomena
that occur outside the library, and accurately reveal effects due specifically and only to manipulation of the independent variable.
Construct validity – the extent to which variables measure what they are supposed to measure
External validity – the degree to which the findings of a study can be generalized to other people, settings, or situations
Internal validity – the degree to which the effects observed in an experiment are due to the independent variable and not to the confounds
Reliability – the degree to which a measure is stable and consistent over time Accuracy – the degree to which an experimental measure is free from error
Data can be affected by random/unsystematic error, which is where each measurement will tend to overestimate or underestimate the duration due to human error. Data can also be affected by systematic error/bias, because the amount of error introduced into each measurement is constant.
The first step in evaluating data is looking at the raw values, or data that are as close as possible to the form in which they were collected.
Descriptive statistics – statistics that summarize the data collected in the study
Central tendency – a measure that represents the typical response or the behavior of a group as a whole
Mean – a measure of central tendency that is the arithmetic average of a set of numbers
Median – a measure of central tendency that is the value of numbers that falls exactly halfway between the lowest and highest values
Mode – a measure of central tendency that is the most frequent score or value in a set of numbers
Variability – in a set of numbers, how widely dispersed the values are from each other and the mean
Standard deviation – a statistical measure of how far away each value is, on average, from the mean
To examine a relationship between two variables, create a scatterplot. With this, you can analyze the relationship and create a correlation coefficient, which is a descriptive statistic that indicates the strength of the relationship between two variables.
Researchers use descriptive statistics to summarize texts, while they use inferential statistics to determine whether effects actually exist in the populations from which samples are drawn.
Metaanalysis – a “study of studies” that combines the findings of multiple studies to arrive at a conclusions
How Does the Nervous System Operate?
The nervous system is responsible for everything that people think, feel, or do.
Neurons – the basic units of the nervous system; cells that retrieve, integrate, and transmit information in the nervous system. They operate through electrical impulses, communicate with other neurons through chemical signals, and form neural networks
The nervous system has two basic divisions:
1. Central Nervous System (CNS) – consists of the brain and the spinal cord 2. Peripheral Nervous System (PNS) – all nerve cells in the body that are not part of the central nervous system, also includes the somatic and autonomic nervous systems
There are basic types of neurons and sensory neurons:
1. Sensory neurons – detect information from the physical world and pass that information to the brain
2. Motor neurons – direct muscles to contract or relax, thereby producing movement 3. Interneurons – communicate within local or short distance circuits
Basic pieces of the neuron structure:
Dendrites – branchlike extensions of the neuron that detect information from other neurons
Cell body – the site in the neuron where information from thousands of other neurons is collected and integrated
Axon – a long narrow outgrowth of a neuron by which information is transmitted to other neurons
Terminal buttons – at the end of axons, small nodules that release chemical signals from the neuron into the synapse
Synapse – the gap between the axon of a “sending” neuron and the dendrites of a “receiving” neuron; the site at which chemical communication occurs between neurons
Membrane – semipermeable, covers the neuron, a fatty barrier that does not dissolve in the watery environment inside and outside the neuron
Ion channels – specialized pores inside the membrane that allow ions to pass in and out of the cell; there are sodium and potassium ion channels
When a neuron is resting, it has resting membrane potential, where the electrical charge inside the neuron is more negatively charged than the outside. To maintain resting potential, the sodiumpotassium pump increases potassium and decreases sodium inside the neuron. Sodium ions pass through the sodium channel, and potassium passes through the potassium channel.
Once a neuron receives a signal, it responds by changing electrically and passing its signals to other neurons. An action potential is the electrical signal that passes along the axon.
A neuron receives chemical signals from nearby neurons through its dendrites. There are two types of signals:
1. Excitatory – depolarize the cell membrane (decreases the negative charge inside the cell) 2. Inhibitory – hyperpolarize the cell (increases the negative charge inside the cell)
When there is a change in voltage (the neuron receives a signal), sodium ion channels open first, rushing sodium inside the cell making the inside more positively charged. Then, the potassium ion channels open second, rushing potassium outside of the cell, making the inside even more positively charged.
The action potential always moves down the axon away from the cell body to the terminal buttons.
Myelin sheath – a fatty material, made up of glial cells, the insulates some axons to allow for faster movement of electrical impulses along the axon.
Nodes of Ranvier – small gaps of exposed axon, between the segments of myelin sheath, where action potentials take place
Allornone principle – the principle that when a neuron fires, it fires with the same potency each time; a neuron either fires or not – it cannot partially fire, although the frequency of firing can vary
When depolarized enough, it reaches a threshold. Once the threshold is reached, the membrane goes back to resting potential through the sodium potassium pump. Potassium ion channels close first, and the sodium ion channels close second.
The neuron that sends a signal is known as the presynaptic neuron, and the one that receives the signal is known as the postsynaptic neuron.
Neurotransmitters – chemical substances that transmit signals from one neuron to another
Receptors – in neurons, specialized protein molecules on the postsynaptic membrane; neurotransmitters bind to these molecules after passing across the synapse
The three major events that determine the neurotransmitter’s influence in the synapse are:
1. Reuptake – process whereby a neurotransmitter is taken back into the presynaptic terminal buttons thereby stopping its activity
2. Enzyme deactivation – occurs when an enzyme destroys the neurotransmitter in the synapse 3. Autoreception – when excess neurotransmitters are detected, they signal the presynaptic neuron to stop releasing the neurotransmitter
Drugs and toxins that enhance the actions of neurotransmitters are known as agonists, while those that inhibit these actions are known as antagonists.
There are eight main types of neurotransmitters:
1. Acetylcholine – responsible for more control over muscles, learning, memory, sleeping, and dreaming
2. Epinephrine – responsible for energy
3. Norepinephrine – responsible for arousal, vigilance, and attention
4. Serotonin – responsible for emotional states and impulsiveness, and dreaming 5. Dopamine – responsible for reward and motivation, and motor control over voluntary movement
6. GABA (gammaaminobutyric acid) – responsible for inhibition of action potentials and anxiety reduction
7. Glutamate – responsible for learning and memory, and pain reduction 8. Endorphins – responsible for pain reduction, and reward
What Are the Basic Brain Structures and Their Functions?
Broca’s area – a small portion of the left frontal region of the brain, crucial for the production of language
Measurements of the bodily systems are examples of psychophysiological assessment, which is when researchers examine how bodily functions change in association with behaviors or mental states. Electrophysiology is a data collection method that measures electrical activities in the brain, measured with an electroencephalograph.
Types of brain imaging:
1. Positron emission topography (PET) – assesses metabolic activity by using a radioactive substance injected into the bloodstream
2. Magnetic resonance imaging (MRI) – uses a powerful magnetic field to produce highquality images of the brain
3. Functional magnetic resonance imaging (fMRI) – used to examine changes in the activity of the working human brain by measuring the blood’s oxygen levels
4. Transcranial magnetic stimulation (TMS) – the use of strong magnets to briefly interrupt normal brain activity as a way to study brain regions
Spinal cord – made up of gray matter and white matter, connects to the skull
Brain stem – an extension of the spinal cord; it houses structures that control functions associated with survival, such as heart rate, breathing, swallowing, vomiting, urination, and orgasm; consists of midbrain, pons, and medulla oblongata
Cerebellum – a large, convoluted protuberance at the back of the brain stem; it is essential for coordinated movement and balance
Forebrain consists of left and right hemispheres.
Thalamus – the gateway to the brain; it receives almost all incoming sensory information before that information reaches the cortex
Hypothalamus – a brain structure that is involved in the regulation of body functions, including body temperature, body rhythms, blood pressure, and blood glucose levels; it also influences our basic motivated behaviors
Hippocampus – a brain structure that is associated with the formation of memories
Amygdala – a brain structure that serves a vital role in learning to associate things with emotional responses and in processing emotional information
Basal Ganglia – a system of subcortical structures that are important for the planning and production of movement
Cerebral Cortex – the outer layer of brain tissue, which forms the convoluted surface of the brain; the site of all thoughts, perceptions, and complex behaviors
Corpus Callosum – a massive bridge of millions of axons that connects the hemispheres and allows information to flow between them
Occipital lobes – regions of the cerebral cortex – at the back of the brain – important for vision
Parietal lobes – regions of the cerebral cortex – in front of the occipital lobes and behind the frontal lobes – important for the sense of touch and for attention to the environment
Temporal lobes – regions of the cerebral cortex – below the parietal lobes and in front of the occipital lobes – important for processing auditory information, for memory, and for object and face perception
Frontal lobes – regions of the cerebral cortex – at the front of the brain – important for movement and higherlevel psychological processes associated with the prefrontal cortex
Prefrontal Cortex – the foremost portion of the frontal lobes, especially prominent in humans; important for attention, working memory, decision making, appropriate social behavior, and personality
In the late 1930’s, Antonio Egas Moniz developed the lobotomy, a form of surgery that damaged the prefrontal cortex to find a way to treat patients in mental institutions. Split brain is a condition that occurs when the corpus callosum is surgically cut and the two hemispheres of the brain do not receive information directly from each other.
How Does the Brain Communicate with the Body?
Somatic nervous system – a component of the peripheral nervous system; it transmits sensory signals and motor signals between the central nervous system and the skin, muscles, and joints
Autonomic nervous system – a component of the peripheral nervous system; it transmits sensory signals and motor signals between the central nervous system and the body’s glands and internal organs
∙ Sympathetic division – a division of the autonomic nervous system; it prepares the body for action
∙ Parasympathetic division – a division of the autonomic nervous system; it returns the body to its resting state
The endocrine system is a communication network that influences thoughts, behaviors, and actions. It works together with the nervous system. The system sends hormones, which are chemical substances, released from endocrine glands, that travel through the bloodstream to targeted tissues; the tissues are subsequently influenced by the hormones.
Gonads – the main endocrine glands involved in sexual behavior: in males, the testes; in females, the ovaries
The Hypothalamus and the major endocrine glands:
1. Hypothalamus – controls motivation and regulates body functions
2. Pituitary – governs release of hormones
3. Thyroid – controls how body burns energy
4. Parathyroid – maintains calcium levels
5. Thymus – governs immune system
6. Adrenal – governs immune system
7. Pancreas – controls digestion
8. Ovaries and Testes – influence reproduction
Ultimately, the endocrine system is under the central nervous system’s control. The brain interprets external and internal stimuli, then sends signals to the endocrine system. The endocrine system responds by initiating various effects on the body and on behavior.
How Does the Brain Change?
In general, males have larger brains than females. Females show greater use of languagerelated brain regions, whereas males show greater use of spatialrelated brain regions.
Brain plasticity decreases with age. Changes in the brain are most likely in the strength of existing connections. However, the brain is always inquiring memories and knowledge. Even into very old age, the brain can grow new connections among neurons and even grow neurons. This is what makes the brain able to heal from injuries. The brain can reorganize after a brain injury. However, children’s brains demonstrate much greater reorganization after a brain injury than adult’s brains.
An understanding of the brain’s organization and plasticity has enabled researchers to better understand conditions such as phantom limb syndrome. Neurogenesis, the creations of new neurons, may underlie neural plasticity.
What Is the Genetic Basis of Psychological Science?
Environmental factors can affect gene expression, which is whether a particular gene is turned on or off. One’s genes and every experience one ever has influences the development of one’s brain.
Genome – the master blueprint that provides details instructions for everything
Chromosomes – structures within the cell body that are made up of DNA, segments of which compromise individual genes
Genes – the units of heredity that help determine the characteristics of an organism Proteins – basic chemical that make up the structure of cells and direct their activities Heredity involves passing along genes through reproduction.
Dominant gene – a gene that is expressed in the offspring whenever it is present
Recessive gene – a gene that is expressed only when it is matched with a similar gene from the other parent
Genotype – the genetic constitution of an organism, determined at the moment of conception
Phenotype – observable physical characteristics, which result from both genetic and environmental influences
Traits are polygenic, meaning it is influenced by genes. A person has specific genes made up in the sex chromosomes. Females have two X chromosomes, while males have an X and a Y. Once a sperm fertilizes an egg, the zygote will contain 23 pairs of chromosomes, half from the mother and half from the father, accounting for genetic variation. The zygote grows through cell division. Sometimes, there are problems in division and the making up of the DNA which leads to mutations, like sicklecell disease.
Monozygotic twins, or identical twins, result from one zygote that divides in two. Dizygotic twins, sometimes referred to as fraternal or nonidentical twins, result when two separate zygotes develop in the womb simultaneously.
Genes also effect behavior.
Heredity – transmission of characteristics from parents to offspring by means of genes
Heritability – a statistical estimate of the extent to which variation in a trait within population is due to genetics
Epigenetics – study of how environment affects genetic expression
Genetic expression can also be modified.
Optogenetics – biological technique which involves the use of light to control cells in living tissue, typically neurons, that have been genetically modified to express lightsensitive ion channels