Psychology Midterm 1 Notes PDF

**Psychology Midterm 1 notes** **Psychology:** the scientific study of the mind, brain, and behaviour -Levels of Analysis -**Social Culture Influences (behaviour):** social or behavioural level, involves relating to others and personal relationships -**Psychological (mind):** mental level, invol...

**Psychology Midterm 1 notes** **Psychology:** the scientific study of the mind, brain, and behaviour -Levels of Analysis -**Social Culture Influences (behaviour):** social or behavioural level, involves relating to others and personal relationships -**Psychological (mind):** mental level, involves thoughts, feelings, and emotions -**Biological (brain):** molecular or neurochemical level, involves molecules and brain structures **Main Challenges in Psychology** **-1 Actions are multiply determined** **-**occur at different levels of explanation -beware of single-variable explanations -**2 Psychological influences are rarely independent** **-**factors may be highly associated with one another -difficult to pinpoint which cause or causes are operating -**3 Individual differences among people** **-**people are different in terms of: thinking, emotion, personality, and behaviour -gender, ethnicity, age, cultural differences -challenging to come up with explanations that apply to everyone **Scientific Theory:** Explanation for a large number of findings in the natural world -ex: negative attentional bias in depression **Hypothesis:** testable prediction derived from a scientific theory -ex: depressed individuals will focus more on negative words in a memory test compared to non-depressed individuals **Conformation Bias:** tendency to seek out evidence that supports our hypotheses and deny, dismiss, or distort evidence that contradicts them -ex: biased search for information- "are dogs better than cats?" "are cats better than dogs?" -ex: Hastorf and Cantril Football Game Study -Dartmouth fans saw Princeton players as committing more penalties and vice versa **Psychological Pseudoscience:** a set of claims that seems scientific, but isn't -pseudoscientific claims are testable -Dangers -**Opportunity cost (indirect harm):** people may forgo opportunities to seek effective treatments -**Direct Harm:** can cause psychological or physical harm (even death) -**An inability to think scientifically as citizens** **Warning signs of Pseudoscience** **-1 Overreliance on anecdotes** **-**anecdote is a story about a single person -anecdotes do not provide information on cause and effect and do not tell us how representative the cases are -**2 Meaningless "psychobabble"** **-**using scientific-sounding words that don't really mean anything (e.g., neuropower, orgone energy accumulator) -**3 Talk of "proof" instead of \"evidence"** **-**science provides **Scientific skepticism:** evaluating all claims with an open mind, but insisting on persuasive evidence before accepting them **Scientific Thinking Principles** **-1 Ruling Out Rival Hypotheses (alternative explanations)** **-2 Correlation Isn't Causation** **-correlation-causation-fallacy:** error of assuming that because one thing is associated with another, it must cause the other -**variable:** anything that can vary (ex: height, age, weight, IQ, income, extroversion, anxiety rating, memory scores, brain activity) -**3 Falsifiability** **-falsifiable:** capable of being disproven -**4 Replicability:** when a study's findings are able to be duplicated, ideally by independent investigators -it is important to know the study's methods and participants -if it can't be duplicated, it increases the odds it was due to chance -ex: the 'supersynapse app' said that 5 studies were done about it, *but* the studies were not done by independent researchers (possibly biased), and no details were noted -**5 Extraordinary Claims** **-**extraordinary claims require extraordinary evidence -the more a claim contradicts what we already know, the more persuasive the evidence must be to accept it -ex: "this medication is guaranteed to help everyone" = extraordinary claim -**6 Occam's Razor (Principle of Parsimony):** if two explanations account equally well for a phenomenon, we should generally select the more parsimonious (simpler) one -ex: crop circles- aliens or pranksters? **History of Psychology** **Early Psychology-Study of the mind** **-Psychology in Greek philosophy** **-psychology = psyche + logos** **-psyche:** soul, spirit, or mind -**logos:** the study of a subject -Socrates, Plato, and Aristotle debated the mind and body, and nativism vs. empiricism (nature vs. nurture) **-Rene Descartes** **-**noted that some human behaviour is mechanistic like the behaviour of animals (body \[physical reflexes\]) and other behaviour appeared to be based on reason (mind \[soul\]) -proposed **dualism:** the idea that our body and mind are separate -saw the mind as being in the pineal gland, as it is in the center of the brain **-Naci, Owen, and Colleagues**: conducted a modern day mind vs. body experiment -had healthy participants and a brain injured (vegetative) patient view a suspenseful Hitchcock movie whilst in an fMRI, and found that moment-to-moment brain activity for both the healthy and vegetative patient was highly similar -showed that the mind is hidden from view and difficult to study -**Donders Decision Making Experiment:** How long does it take a person to make a decision? -**Reaction Time:** how long it takes to respond to a stimulus -**simple RT:** subject presses a lever or button when a light is turned on -**choice RT:** more complicated, a subject has to press one of two buttons -**choice RT -- Simple RT = Decision time** **-**choice RT is typically 100 milliseconds longer than simple RT -Important as it was one of the first psychological experiments, and showed that mental responses cannot be measured directly, but can be inferred from behaviour -**Wilhelm Wundt:** developed first psychology lab in Leipzig **-**scientifically examine consciousness- the awareness of immediate experience (how different must two colours be to tell them apart? How long does it take to react to a sound? What thoughts occur when we solve a math problem?) -Methods: 1) RT experiments 2) **Introspection:** trained observers carefully reflect and report on their mental experiences (visual stimuli or auditory tones) **Structuralism:** aimed to identify the basic elements of the psychological experience (asks 'what' questions) **-Edward Titchener** (was a student of Wundt) **-**used introspection -wanted a comprehensive map of the elements of consciousness -problems with structuralism -reports are subjective, not objective (too cold in the room vs. the temperature in here is 10 degrees c) -**imageless thought:** thinking that occurs without images or sensory content (Oswald Kulpe) -lasting scientific influence of structuralism -correctly emphasized the importance of systematic observation -Wundt's methods used qualitative and quantitative data **Ebbinghaus** **-**memory and forgetting (studied a list of nonsense syllables and then said them aloud. Repeated them until he had each list perfectly memorized.) -how rapidly do we lose learned information? (measured how long it took to re-memorize the list after different intervals of time) -savings formula: savings measure (original time to learn list) minus time to relearn the list after a delay -**Ebbinghaus' forgetting curve:** shows savings as a function of retention interval (the more time that passes means that it will take longer to relearn the material) -difference in relearning after two days vs. 31 days is approximately the same, meaning that we need to review material withing two days of initially learning it **Functionalism:** asks 'why' questions **-William James** -observations based on the functions of his own mind, not experiments **Behaviourism:** focuses on uncovering the general principles of learning underlying animal and human behaviour -eliminated the study of the mind -founded by **John B. Watson** **-**criticized the study of consciousness -psychological science must be objective, not subjective -focused on classical conditioning -association between things (ex: when a fire alarm sounds, you immediately get up and leave a building) -understand human behaviour (responses) in relation to external/environmental factors (stimuli) -**B.F. Skinner:** examined operant conditioning -rewards and punishments -lasting influence of behaviourism -influential in models of human and animal learning -still in use today **Reemergence of the Mind in Psychology** **-Tolman** **-**trained rats to find food in a four armed maze. When a rat was placed in a different arm of the maze, it went to the specific arm where it previously found food -believed that the rat created a **cognitive map**, a representation of the maze in its mind **-Cognitivism:** arose in response to the behaviourists -**information-processing approach:** insights from the digital computer -mind operating in terms of stages/sequences -**cognitive psychology:** the study of mental processes (perception, attention, memory, emotions, language, deciding, thinking, and reasoning) -thinking affects our behaviour in powerful ways (ex: interpretation of rewards and punishments, some might find a B grade good, others bad) -**Piaget:** posited that children think differently than adults -**cognitive neuroscience:** examines the relationship between brain activity and thinking **Psychoanalysis:** focuses on internal psychological processes of which we are unaware -**unconscious mind:** contains thoughts, memories, and desires below the surface of conscious awareness -**Sigmund Freud** **-**felt that sexuality and aggression were repressed and in the unconscious -**Freudian Slips** (ex: I decided to take a summer school curse \[instead of course\]) -psychological life is filled with symbols -concept of the unconscious based on observation -other components of psychoanalysis -dream analysis -strong role of childhood experiences (childhood has a large role to play) -criticisms of psychoanalysis -difficult to falsify -sexist -positives about psychoanalysis -importance of childhood development -the idea that some processing is unconscious (ex: biases, priming) -**priming:** the effect if words are related in meaning (ex: the word pair of 'bread' and 'butter' vs. the word pair of \'bread' and 'computer' **Humanism:** emphasizes unique qualities of humans, free will, and the potential for personal growth -began in 1950's in opposition to behaviourism and psychoanalysis -free will and the potential for growth -**Abraham Maslow:** psychological disorders result from hindering of human needs -hierarchy of needs **Modern Psychology** **-Clinical psychologist:** focus is mental disorders -**Psychiatrists:** focus is medicine and mental disorders -**Counselling Psychologist:** focus is temporary problems -**School psychologist:** focus is helping children and youth -**Developmental psychologist:** study how and why people change over time -**Experimental Psychologist:** use research methods to study perception, attention and memory, language, thinking, social behaviour -**Biological Psychologist:** examine the physiological bases of behaviour in animals and humans -**Forensic Psychologist:** assess and diagnose inmates. Conducts research -**industrial-organizational psychologist:** work with companies to: select/evaluate employees, research working environment conditions -**evolutionary psychology:** applies Darwin's theory of natural selection to human and animal behaviour (ex: anxiety warns us of upcoming danger....or deadlines?) -very controversial **Research Methods** **Research Methodology:** a way to systematically solve or answer a research problem -selection of the research method is crucial for what conclusions you can make **3 Guiding Principles for Applying the Scientific Method to Psychology** **-1 Generalizability:** is a measure of how useful the results of a study are for a broader group of people or situations -also called **external validity** -to do this, we need a representative sample of the population -the sample depends on the research question -Since Ebbinghaus only experimented on himself with his memory experiment, that would equate to low external validity -Should always ask ourselves if our findings are **W.E.I.R.D - Western, Educated, Industrialized, Rich, Democratic** **-**2010 review of social and behavioural science studies found that W.E.I.R.D people represented around 80% of study participants -way to increase generalizability -ex: use list of Canadian census population data, randomly scramble names, contact every 1000^th^ person -- or use a list of 1000 customers, randomly scramble names, contact every 5^th^ person to get a sample of 200 people \- if a larger sample is not random, it is better to have a smaller random sample -- ex: it would be better to ask 100 people across Canada about Drake than it would be to ask 100 000 people from Toronto (since it is his hometown, and people are more likely to be biased there) -**2 Reliability:** consistency of measurement -a reliable questionnaire should yield similar scores over time = **test-retest reliability** **-Interrater reliability:** extent to which different people agree on the characteristics they are measuring -ex: two psychologists giving separate diagnoses = low interrater reliability -ex: job interview panel all liking a candidate = high interrater reliability -**3 Validity (Construct Validity):** extent to which a measure assesses what it claims to measure -ex: a word test is not a good test of numerical ability = low validity -ex: a math test to measure numerical ability = high validity -a **valid** test must also be **reliable**, but a reliable test can be completely invalid -ex: a polygraph could be reliable but be invalid, as it's actually measuring a person's stress level -ex: finger measurements to test for intelligence would have test-retest reliability and interrater reliability as the finger measurements should remain the same, and other researchers should agree the measurements are accurate, but it would not be valid, as the length of ones finger does not equate to intelligence levels **5 Types of Research Designs** -Psychologists can't always exert experimental control over variables, only describe patterns of behaviour and discover links/associations between variables -**1 Naturalistic observation:** watching behaviour in real- world settings without trying to manipulate the situation -can be conducted in real time or via video recordings, and also via social media and wearable technologies -ex: Jane Goodall observing Chimps -ex: Robert Provine's Investigation of Laughter -ex: Wansink and van Ittersum's Buffet Study -Pros of Naturalistic Observation Studies -high in external validity (since they take place in the real world, they should be) -good starting point -can study animal behaviour -Cons of Naturalistic Observation Studies -low internal validity -cannot draw cause-and effect inferences **-2 Case Study:** examine one person or a small number of people -used to study rare brain damage and/or unusual conditions -can inspire new hypotheses about the brain and behaviour -ex: Henry Molaison (experimental operation to remove portions of the hippocampus. Observed by Dr. Brenda Milner from McGill. Inability to form new memories) -ex: Prosopagnosia: extreme impairment of the ability to recognize faces (fusiform face area \[FFA\] responds specifically to faces) -Pros of Case studies -high level of detail of rare psychological phenomenon -Cons of Case Studies -low on both external and internal validity **-3 Self Report Measures and Surveys** **-self report measures (questionnaires):** assess participant characteristics -demographics, personality traits, mental illnesses -**surveys:** measure opinions and attitudes -market research, political polls -challenges to surveys -people's responses can vary depending on how the question is presented (open-ended vs. multiple choice format, agree/disagree format (one statement) vs. multiple choice format) (agree/disagree "the best way to ensure peace is through military strength \[55% agree, 42% disagree\]) (multiple choice "the best way to ensure peace is through military strength" \[33%\] or "diplomacy is the best way to ensure peace" \[55%\]) -pros of self report measures (questionnaires) -easy to administer -get direct information about emotions, personality, opinions -cons of self report measures -potential for dishonesty **-4 Correlational Designs:** strength of association between two variables -correlations can be negative, zero, or positive -correlation coefficients range from -1.0 (perfect negative correlation) to +1.0 (perfect positive correlation) -higher absolute value means stronger relationship -correlation does not equal causation **-5 Experimental Designs:** permit cause and effect inferences -only way you can make a causal claim -high on internal validity -two essential components: -**random assignment:** randomly sort participants into one of two groups -1 **experimental group:** receives manipulation -2 **control group:** does not receive manipulation -**between-subjects design:** need random assignment to avoid biases -**within-subject design:** participants are their own control group (don't need random assignment) -might have fatigue effect since participants are both groups -**independent variable:** variable that is manipulated -ex: music vs. no music, antidepressant vs. sugar pill -**dependent variable:** variable the experimenter measures to see if the manipulation has an effect -ex: typing performance, level of depression -ex: if one is conducting an experiment to see if distracting music influences typing performance, the independent variable would be the music, the dependent variable would be typing performance -experiments have high internal validity if the independent variable is the only difference between the experimental and control groups -ex: a confounding variable would be if the experimental group (ex: the one with music playing) had a very hot room temperature, and the control group (the one with no music) had a normal room temperature. The room temperature would be the confounding variable -**Placebo effect:** improvement because you expect improvement -ex: experimental group receives medication and states their anxiety decreases, control group receives nothing and states their anxiety stays the same- can't be sure the experimental group is saying their anxiety decreased because they are expecting it or not -need an experimental group (receives medication), placebo group (receives sugar pills) and a control group (receives nothing). Participants must be blind to what group they are in for results to be accurate = **blind design** -**experimenter expectancy effect:** researchers' hypotheses lead them to unintentionally bias their outcome -ex: one group measuring how fast rats make it through a maze told they have bright rats, the other group told they have dull rats. Group told they have fast rats will report their rats as faster and the group told they have dull rats will report their rats as slower, even though in reality both groups have the same rats -**Double blind designs:** experimenter and participants unaware of the treatment -prevents experimenter expectancy effect and the placebo effect **-Demand Characteristics:** cues that participants pick up allowing them to guess the researcher's hypothesis -ex: study titled 'the effects of horror movies on mood' (not good) vs. study titled 'study on university student's film preferences' (better) -need to work to conceal the true purpose of the study (without being unethical) -**reactivity:** refers to the tendency of participants to change their behaviour when they know that they are being observed -behaviour might become more positive or negative depending on the situation -**social desirability bias/positive impression management:** our tendency to respond in ways that we feel are more appropriate or socially acceptable to others -**response sets:** tendency of participants to distort their self-report responses in a positive way -could be to try to impress the researcher **Statistics in Psychology research** **-descriptive statistics:** organize data into meaningful patterns and summaries -**central tendency:** where the group data tends to cluster -3 main measures- **mean, median, and mode** (mean is affected by outliers, but the median and mode are not) **-mean:** average of all scores -**median:** middle score in the data -**mode:** most frequent score in the data -**Variance:** how loosely or closely scores are clustered -**range:** difference between the highest and lowest scores -**standard deviation:** how far each data point is from the mean **Ethical Issues in Research Design** **-Tuskegee Syphilis Study (1932-1972)** **-**participants, 399 African American men, were diagnosed with syphilis, but not informed -not given treatments, even though treatments were available \- **Stanley Milgram's Obedience study** **-**measured the willingness of study participants to obey an authority figure -administered 'shocks' to a 'learner' -were not informed that the shocks weren't real and that the 'learner' was part of the study, and many people suffered psychological distress following the experiment because of it **Ethical Guidelines for Research** **-Research Ethics Boards (REBs):** oversee research on humans and animals -**informed consent:** participants must know what is involved in the study prior to participation (purpose, duration, any potential risks or adverse effects, right to withdraw) -**debriefing:** at the end of the study, participants should be fully debriefed about the true nature of the research -should be informed of any deception that was used **Biological Psychology** **Biological psychology:** studies the relationship between the nervous system and behaviour **Central nervous system:** brain and spinal cord **Peripheral nervous system:** all nerves outside the brain and spinal cord (is divided into two branches) **-somatic nervous system:** controlling and coordinating voluntary movement **-autonomic nervous system:** controls the involuntary actions of our internal organs and glands -- also has 2 divisions -**parasympathetic division:** more relaxed state- rest and digest (pupil constriction, slow heartbeat, stimulates digestive system activity, etc)- a return to homeostasis -**sympathetic division:** fight or flight- production of adrenaline (pupil dilation, increases heartbeat, decreases digestive system activity, etc) **Brain Mapping Methods** **Phrenology:** one of the earliest brain mapping methods -skull shape-\> brain size-\> psychological traits -- thought skull shape was akin to our brain size and our psychological traits -is falsifiable -major positive contribution: **spatial organization** **-spatial organization:** different functions are located on different areas of the brain **Neuropsychology:** links areas of brain damage to cognitive function -animal models to map out certain functions in the human brain -standardized tests- neuropsychology tests are standardized -**MoCA (Montreal Cognitive Assessment)** is a standardized cognitive assessment test **Localization of Function:** specific functions are served by specific areas of the brain -ex: **Broca's Aphasia:** language production is impaired by frontal lobe damage -can't produce speech, but are able to understand speech -ex: **Wernicke's Aphasia:** damage to the temporal lobe -spared production, impaired comprehension -long complete sentences that lack meaning, adding unnecessary words and creating made-up words **Double Dissociation:** if damage to one area causes function A to be absent while function B is present, and damage to another area causes function B to be absent while function A is present -ex: if Production is function A and Comprehension is function B, then with Broca's aphasia function A is absent and function B is present, while with Wernicke's aphasia function A is present while function B is absent **Electrical Stimulation** **-Wilder Penfield-** stimulated the brain of one of his patients with electrical probes to assess the function of different regions (E.g. motor cortex, temporal lobes) (what parts of the brain are tied to specific functions) -showed that brain cells use electrical activity to send information **Electroencephalograph (EEG):** measures electrical activity via electrodes on the skull -detects electrical change in the range of milliseconds- really good at timing information -is a functional method (measures brain activity) -better at when than where information -**ERP (event-related potential):** timing of brain activity in relation to certain cognitive events -show how activity can change in relation to cognitive events (e.g. noticing a novel stimulus) -derived from averaging EEG signals (derived from the mean of EEG brain waves) -P3 ERP component plays a role in attention and stimulus novelty -demonstrates fast timing information (millisecond scale) **Neuroimaging Techniques: Structural:** looks at the appearance of the brain, but does not show activity -**Computed Tomography (CT scan):** uses x-rays to construct 3D images -**Magnetic Resonance Imaging (MRI scan):** uses magnetic fields to indirectly visualize brain structure -measures the release of energy from water molecules in biological tissues in relation to the magnetic field and application of a radiofrequency current **Neuroimaging Techniques: Functional:** -**Positron Emission Tomography (PET scan):** measures consumption of radioactive glucose-like molecules to give a picture of neural activity (good for spatial information, not great for timing) (measures activity on a scale off seconds instead of milliseconds) -**Function MRI (fMRI scan):** uses magnetic fields to visualize brain activity using changes in blood oxygen level (blood-oxygen-level-dependent \[BOLD\] signal) (good for spatial information, not great for timing)(measures activity on a scale of seconds instead of milliseconds) **Magnetoencephalography (MEG):** detects brain activity by measuring tiny magnetic fields generated by the brain -spatial distributions of magnetic fields can be superimposed onto an MRI scan -has both structural (spatial) and functional (temporal) information (temporal information on an ms scale) **Manipulating the Brain** **-Deep Brain Stimulation (DBS):** modifies brain function through implanted electrodes -potential treatment for treatment resistant disorders ( parkinsons, ocd, depression) \- is invasive -**Transcranial Magnetic Stimulation (TMS):** applies strong and quickly changing magnetic fields to the surface of the skull that can either enhance or interrupt brain function **Neurons** **-**early scientists originally though that the brain was composed of a **nerve net** (everything joined) **Neuron doctrine:** individual nerve cells transmit signals and are not continuously linked with other cells (Santiago Ramon y Cajal) **Neurons:** nerve cell specialized for communication -electrified membrane gives it special properties **Parts of the Neuron** **-Dendrites:** branch-like extensions that receive information (increased surface area) -**Cell body (soma):** contains mechanisms to keep the cell alive -where information from the dendrites assembles -cell would not be able to function if it gets damaged -**Axons and Axon Terminals:** transmits signals (information) to other neurons -electrical signal (nerve impulse) inside axon -**Synaptic vesicles:** are spherical sacs containing neurotransmitters **Synaptic Transmission:** neurons communicate via a combination of electrical and chemical signals -the signal within the neuron is electrical, outside of the neuron the signal is chemical **Synapse:** all components in figure (see slides) **Synaptic cleft:** gap between two connecting neurons through which messages are transmitted chemically -chemical signal in synapse/synaptic cleft (release of neurotransmitters) **Glial Cells** **-Astrocytes:** regulate blood flow. Are found in the blood brain barrier. Increase accuracy of neural transmission -**Oligodendrocytes:** promote new connections and healing. Produce the myelin sheath around axons- increases speed **Action Potential:** electrical impulse that travels down the axon, triggering the release of neurotransmitters (+40 mV) -is an all-or-none response -is followed by an absolute refractory period (limits maximal firing rate) -three stages occur during action potential -**1 Depolarization:** sodium channels open and sodium rushes into the cell -**2 Repolarization:** potassium channels open and potassium stats to leave cell \- **3 Hyperpolarization** **-resting potential** is -70mV -the **threshold of excitation is** -55mV (if the neuron does not reach this threshold it will not fire) -when the neuron is below -70mV it is in the **absolute refractory period** (follows the neuron firing and reaching action potential) **Neurotransmission** **-**receptor sites are specialized to receive only certain types of neurotransmitters **-reuptake:** when neurotransmitters go back into the axon terminal **Key Neurotransmitters** **-Glutamate:** Function = excitatory (ex: enhanced learning and memory) **-GABA:** Function = inhibitory (ex: anti-anxiety drugs) -**Dopamine:** Function = motor function and reward (ex: parkinsons disease) -**Serotonin:** Function = mood, aggression, temperature, sleep, and digestion (ex: treatment for depression) -**Endorphins:** Function = relieves pain, reduce stress (ex: released during exercise) **Psychoactive Drugs** **-Agonists:** increase activity of the NT system -ex: opioids (like codeine and morphine) mimic endorphins -**Reuptake inhibitors:** block the reabsorption of neurotransmittors -ex: anti-depressants -**Antagonists:** decrease activity of the NT system -ex: dopamine blockers for schizophrenia **Major Parts of the Brain** **-Cerebral Cortex** **-Frontal:** executive functions, motor planning, language, and decision making -body is mapped onto the motor cortex, more devoted to face and speech, involves Broca's area and speech production -prefrontal cortex is responsible for thinking, language, mood, personality, self-awareness, self-control -**Parietal:** processes touch information, integrates senses, spatial perception (located at top back of brain) -contains the somatosensory cortex -relays visual and touch information to the motor cortex, and affects spatial perception -**Unilateral Neglect:** fail to attend to opposite side of damage (if right is damaged, can't perceive what's in your left visual field and vice versa) -**Temporal:** processes auditory information, language, and long-term memory -the auditory cortex and Wernicke's area are responsible for speech comprehension -bottom part contains the fusiform face area (FFA) -located at side of brain (over ear) -**Occipital:** processes visual information (very back of brain, behind parietal and temporal lobes) -specialized for vision -**corpus callosum:** connects the two cerebral hemispheres -outer layer of cerebral cortex contains **grey matter,** inner part is **white matter** **-white matter- Diffusion tensor imaging (DTI):** structural imaging technique of white matter tracts (axons) **-split brain surgery:** procedure that involves severing the corpus callosum to reduce the spread of epileptic seizures -not really done anymore due to the aftereffects- brain hemispheres can no longer communicate, problematic because what the right eye sees is processed by the left hemisphere, and what the left eye sees is processed by the right hemisphere -**Phineas Gage** **-**iron rod destroyed most of his left prefrontal cortex, caused remarkable behaviour changes (became rude and impulsive) **Limbic System** **-Amygdala** and **hippocampus:** emotion and memory -**Amygdala:** processes emotions, especially fear and aggression -**hippocampus:** essential for memory formation and spatial navigation -**Thalamus** and **hypothalamus:** sensation relay and basic biological needs **Brain Stem:** relay station between the cortex and the rest of the nervous system -3 Parts -**Cerebellum:** balance and motor skills -**Pons:** dreaming, sleep, arousal -**Medulla:** vital functions