Exam 1 Flashcards
psychology
scientific study of behaviour, thought, experience, and how they are affected by physical, mental, social, and environmental factors
Measuring smoke – fire is not directly measurable; highly variable
biopsychosocial model
individual as the product of many influences
Biological – genes, brain anatomy and function
- some psych and behviour disorders, drug effects, brain behaviour relationships
Psychological – behaviour, perception, thought, experience
- language, memory, decision
Sociocultural – interpersonal relationships, families, groups, societies, ethnicities; can’t live isolated
-Attraction, attitudes and stereotypes, conformity
scientific method
a way of learning about the world through collecting observations, developing theories to explain them, and using the theories to make predictions
Process
- Observation -> develop theory -> develop hypothesis to test theory
- Confirm -> strengthens original theory; develop secondary hypothesis; developing credibility
- Deny -> must revise theory or discard/modify original hypothesis
theory
explanation of a phenomenon; generates and is tested through hypotheses (not opinion/belief)
hypothesis
testable prediction; can be observed and measured; cannot be technically proven
- Will confirm or deny theory
- Falsifiable – hypothesis can be disproven (ex. all swans are white)
building scientific literacy
smart and critical consumers of psychological information; all sectors intertwine together
o Knowledge gathering – what do we already know
o Scientific explanation
o Critical thinking – evaluating the evidence; are sources credible
o Application – why is this research relevant; how does it apply to society and people
why is psych a science
o Empiricism – knowledge gained by careful observation; through theories, hypothesis, research experiments
o Determinism – events governed by lawful, cause and effect relationships; nothing happens for no reason
Ex. gravity
o Psych combines determinism and empiricism – not conflicting; understand behaviour by making observations and testing hypotheses; cause and effect occurs at different levels
Calls free will into question – is everything the result of the biopsychosocial model
circa 1500 BCE
Ancient Egyptian doctors describing behavioural changes following damage to head
circa 430 BCE - 215 AD
Greek (philosopher Hippocrates) and roman (Galen of Pergamon) physicians developed the 4 humours/temperaments theories of personality (ratio of liquids determined personality)
4 humours: o Sanguine (blood) – impulsive, pleasure seeking, charismatic o Choleric (yellow bile) – ambitious, energetic, aggressive o Melancholic (black bile) – independent, perfectionist, introverted o Phlegmatic (phlegm) – quiet, relaxed, content
circa 1600
materialism vs dualism
adoption of scientific method
Growth in physics, astronomy, physiology, biology, and chemistry (not much psych)
Materialism – belief that humans and other living things are composed of exclusively physical matter
- Popular at this time
Dualism – matter and mind are dual properties; there are properties of humans that are not material (mind and soul); immeasurable
- Popular today
- We have not been able to localize consciousness further than “I think therefore I am”
influence from physics
Gustav Fechner (1801-1887) – how energy produces motion:
- Psychophysics – study of the relationship between physical world and mental representation (how things are vs how they are perceived)
- Weight experiment – Weber’s Law; added weight was perceived as less when added to 5lb relative to 1lb weight
- Integrated light and sound
- Created equation to calculate perceived changes of stimulus – at what point does perception change
influences from evolutionary theory
Charles Darwin (1809-1882) – evolution of species; studied adaption to environment
- Natural selection – genetically inherited traits that contribute to survival and reproductive success are more likely to be passed onto next generation
(Applies to behaviours)
- Traits differ across environments
influences from medicine
- year (what field of psych)
- brain function from injury
- leading influences
1800s
Clinical psych – concentrates on the diagnosis and treatment of psych disorders
Localization of brain function – certain parts of brain control specific mental abilities and personality characteristics:
Phrenology – mental traits and disproportions could be determined by examining surface of skull (27 “organs”)
- Franz Gall (1758-1828) and Johann Spurzheim (1776-1832)
Brain injuries
- Paul Broca – left frontal lobe damage (Broca’s area); speaking and word production; Could formulate words and ideas; could not communicate them
- Karl Wernicke – left hemisphere damage (Wernicke’s area); language comprehension
- Phineas Gage – frontal lobe damage; impulsiveness and childlike behaviour
Names:
Franz Mesmer (1734-1815) – believed exposure to magnets could redirect the flow of metallic fluid in the body to cure disease and insanity
- Some patients reported being cured – likely placebo effect
- Now known as hypnosis
Sigmund Freud (1856-1939) – intrigued by hypnosis; theorized unconscious mind fuelled our behaviours & tried to use hypnosis to access this
- Used a medical model and evolutionary influences to determine what motivates and the importance of early life experiences
- Psychoanalysis – access unconscious mind; attempts to explain how unconscious processes influence behaviour and personality
- Believed the unconscious mind contained:
Forgotten memories
Sexual and aggressive urges (Edapis theory – young men were attracted to their mothers)
- Radical and exciting – much was unfounded and untrue
- psychoanalysis is still used today
influences from social science
Sir Francis Galton (1822-1911) – measured perception, used statistical analysis to study behaviour:
Individual differences in people – nature vs nurture; how they influence mental processes
- Nature – heredity (genetic material)
- Nurture – environment
Eminence – combination of ability, morality, and achievement that run in families; belief that there is a hereditary basis for success; nature
- Eugenics – superior race/bloodline; used to justify genocide (ex. holocaust)
- Darwin believed this as well
- Phrenology backed this – superior brains
names of beginning of contemporary psych
Wilhelm Wundt (1832-1920) – first laboratory dedicated to human behaviour (1979)
- Introspection – to look within
- Participant studies
Sensation and perception
Reaction times
- Measured how experimental manipulations affected mental events
- Mental activity is not instantaneous
Ex. reaction times – processes occurring
Experiments showed cause and effect relationships
Edward Titchener (1867-1927) – student of Wundt - Structuralism – analysis of conscious experience by breaking it down into basic elements; understanding how the elements work together; Mental experiences were made up of a limited number of sensations Combined sensations/structural components create conscious experience and mental life
William James (1842-1910) – wrote first psych textbook (Principles of Psych, 1890)
- Studied behaviour in context (instead of structural)
How thoughts and action help us adapt to environment (Darwin)
- Functionalism – study of purpose and function of behaviour and conscious experience
Behaviour is understood by the purpose it served in evolution
behaviourism in contemporary psych (and names)
singular focus on studying only observable behaviour; little to no reference to mental events/instincts ; removed cognition and psychoanalysis
Edwin Twitmyer (1873-1934) – laid groundwork for behaviourism
- Classic conditioning – training behaviour and response (still used today); begs the question why we need thought and experience
- Patellar reflex was associated with sound; reflex could then be produced with sound
- Pavlov’s dogs
Edward Thorndike (1874-1949) – behavioural changes were based on consequence
- Pos – person will do it more
- Neg – do it less
- Parental – learned early on in childhood
John Watson (1878-1958) – only observable changes in environment and behaviour are appropriate for scientific study
- “give me a child” – thought you could train a child to be anything; learning was consequence of behaviour
- Conditioning
B.F Skinner (1904-1990)
- Radical behaviourism – foundation of behaviour is the response to reward and punishment
social and cultural influences (historically)
Norman Triplett (1861-1931) – published first Social Psychological research (1898)
- influence of social situation on behaviour
- holocaust occurring at this time – how could people on mass commit acts of violence
- bike riders – will bike faster in group setting
1940s
- Social psychology – study of influence from other people on behaviour
- Personality psychology – study of how different personality characteristics; influenced by social situation (people by themselves vs in a group setting)
Kurt Lewin (1890-1947) – founder of modern social psychology
- Behaviour is a function of the individual and the environment (nature and nurture)
- social and personality are intertwined domains
cognitive revolution
mainly in Europe; difficulty penetrating through behaviourism; called into question things behaviourism couldn’t explain
Hermann Ebbinghaus (1850-1909) – studied memory
Fredrick Bartlett (1886-1969) – cultural knowledge and previous experience influence our memory
Noam Chomsky – aspects of language (grammar and vocabulary)
Gestalt psychology
- Focuses on the whole of perception and experience, rather than its parts
- Thinking and experiencing occur at higher, more organized levels
Cognitive psych: Ulrich Neisser (1928-2012) – named it
- Modern psych – focused on processing memory, thinking and language
- More than just observable phenomenon – create theories and translate them into behaviour
- Computer/brain analogy – many connections; only see what’s on the “screen”
- Imperfect – computers were created by humans; we understand computers, we don’t understand brains
- Learning more about computers from and using computers to measure brain activity (circular)
humanistic psych
Unique aspects of individuals o Freedom to act o Rational thought o Fundamental differences between humans and animals o Meaning of personal experience
Carl Rogers (1902-1987)
Abraham Maslow (1908-1970) – Maslow’s hierarchy of needs:
o Self actualization – most they can be
o Esteem – respect and recongnition
o Love and belonging
o Safety – social psych went into
o Physiological needs – basic psych went into
brain and behaviour psychologists
Donald Hebb (1904-1985)
o Hebb’s Law – cells that fire together wire together; studied neuronal connections and cellular synapses
- More “talking” = stronger connections (instincts, reflexes, habits)
Wilder Penfield (1891-1976) – mapping sensory and motor brain regions
o Initially used to remove centers of brain in epilepsy patient – shocked areas of brain under local anesthesia to identify parts of brain
- Progressed into brain mapping
o Subjective experience in brain – can be represented in brain in different regions (?)
emerging themes in psych
Psych of women – underrepresented historically
Behaviour in different cultures
o Psych students are WEIRD (white, educated, industrialized, rich, democratic)
Brain imaging
Positive psych – outlook influences wellbeing
Psych in “real world” vs psych in “digital world”
o Digital world is becoming more prominent
o Are studies in lab applicable to real world
research method general goals (3)
Critical thinking
Objectivity – facts about the world can be agreed on by independent observers
- Subjectivity – beliefs, opinions, experiences, expectations
Participation and consumption of research
variable
object/concept being being controlled, manipulated, or measured
o Independent – controlled
o Dependant – outcome; measures effectiveness and manipulation of independent
operational definition
statements that describe the procedures/operations and specific measurements that are used to record observations (detailed explanations of how/what)
5 goals of scientific research
Measurements are objective, valid, and reliable
Generalizable
Techniques reduce bias
Is made public
Can be replicated
Measurements are objective, valid, and reliable (3)
definitions
a. Objective – consistent measurement across instruments and observers (ex. weight and height)
b. Validity – measures what it claims to measure (using correct questions)
c. Reliability – measure provides consistent outcomes from multiple observers or points in time
i. Test-retest – person should score same score when they feel a certain way
ii. Alternate forms – same test with different version should produce same scores
iii. Inter-rater – multiple observers should get the same result
generalizable (& sample types)
degree to which set of results can be applied to other situations/individuals/events
a. Testing very specific is not helpful – less likely to occur in real life
b. Using a large enough sample to represent entire population
i. Random sample – everyone has an equal chance of being selected
ii. Convenience sample – can cause bias; convenience of researcher or participant
techniques reduce bias
a. Researcher bias
i. Demand characteristics – eliciting certain responses because of what they expect to happen; occurs through types of questions, body language, how info is given to participant
b. Subject/participant bias
i. Social desirability – wanting to be a good participant; giving researchers what they want
ii. Hawthorne effect – change in behaviour from being observed
c. Reducing bias
i. Anonymity – reduces social desirability
ii. Confidential – reduces social desirability
iii. Placebo – measure how expectations influence results
iv. Blind procedures
- Single blind – participants don’t know purpose or what treatment they’re given
- Double blind – neither participant or researcher knows; reduces researcher bias as well
is made public
published in academic journals
General public – radio shows and podcasts
can be replicated
repeating study and finding similar outcome every time
Replication crisis – journals are not excited about publishing what is already known:
- Desire to publish creates 2 types of bias
1. research is only done in areas that may produce significant results
2. Influenced/altered to produce significant result - good research should not be influenced by getting a certain result
- null results should still be published
- which is correct? - historical or present?
- Small differences could produce different results
- Many labs project – replicating famous findings to ensure they hold true
- Ex. ManyBabies
poor methods
- Untestable hypothesis – falsifiable
- Anecdotal & relies on subjective experience
- Biased selection of data – does not include all relevant groups
- Appeals to and trusting authority without scientific evidence (ex. Covid-19)
- Appeals to common sense, but lacking scientific evidence
6 research designs
Descriptive
Case studies
Naturalistic observation
Surveys and questionnaires
Correlation research
Experimental research
descriptive
a. Quantitative – calculations; uses numerical measurements and statistics
b. Qualitative – observational; without numerical calculations
c. Both are important – type used should back up type of study conducted
case studies
in depth report about a specific case (unique situation)
Common in clinical psych – use detailed report of one person and use to build case about specific topic
- Freud
- Phineas Gage – case study about prefrontal lobe (frontal lobe?)
Pros – detailed info; rare conditions
Cons – limits generizability
naturalistic observation
unobtrusively observing and recording as it occurs in a natural environment
Jane Goodall
Pros – negates Hawthorne; detailed description in natural environment
Cons – poor control over influential variables
surveys and questionnaires
Self-report – responses are provided directly by subjects
- Face to face
- Phone survey
- Paper and pencil
- Web based
Allows assessment of attitudes, opinions, beliefs, abilities
Cons – poor control; requires participants are truthful (anonymity and confidentiality help)
Pros – Useful in acquiring a lot of data
correlation research
measuring degree of association between 2 or more variables
How do they influence each other
- Synergistic/antagonistic
- If they change with each other – association
Direction
- Positive – same direction (direct)
- Negative – different directions (inverse)
Magnitude – strength -1 to +1 -/+1 = same magnitude of change in each direction - Decimal influences distribution 0 = no association
Pros – shows strength of relationship
Cons
- Third variable problem – 3rd variable influences and makes it appear as though there is a correlation
- Spurious correlation – correlations are there but they are not actually related; must be very specific and have research to back up correlation to avoid this
(Ex. mozza cheese sales and civil engineer doctorates in an area)
- Does not always make conclusions about which variable influences the other
experimental research
Random assignment to groups – participants are equally likely to be placed in either condition
- Ensures that difference in groups is due to variable
- Prevent confounding/unrelated variables interfering with results
- Can include control group
Pros – Increased experimental control and eliminates more outside influence; tests cause and effect
Cons – artificial with limited generalization to real world situations
Designs:
- Independent variable (IV) – manipulates to distinguish between conditions/groups (ex. depression medication)
- Dependant variable (DV) – observation/measurement recorded and compared (ex. depressive symptoms)
- Between subject – 2 separate groups
Pro – don’t need to worry about “carry over” from previous “level” of independent variable
Cons – can always cause different results even with random assignment - Within subject – same group experience all treatments/levels; comparing between time period instead of people
Pros – allows control for individual differences
Cons – there may be “carry over” - Quasi-experimental – groups are selected based on predetermined characteristics
No random assignment
Ex. testing specific drug – need subjects with specific medical condition
ethical conduct
o Informed consent – agree beforehand or debriefed immediately afterward if deception is required
o Anonymity and confidentiality – or explain why this is absolutely unavoidable
o Collection, storage, and reporting of data – stored separately from identity data
Data must be disclosed – how you use it and what kind of identifying info is involved
o Animal welfare – basic care; minimization of pain or discomfort if it’s necessary
ethics in psych study
Benefits must outweigh the risks
Lot of room for harm in psych – emotionally, mentally, physically
ethics board
Research ethics board (REB) – committee at an institution responsible for protection of human participants
Detailed study must be signed off as ethical
unethical examples
o Freud – unconscious fears in little hands experiment; associated loud noise with bunny, child became afraid of bunny
o Prison experiment – abuse and psychological harm
purpose of statistics
Do these support or reject hypothesis
Organizing data into “big picture”
Are the differences between groups meaningful
descriptive statistics
Techniques used to organize, summarize, and interpret data
- Frequency
- Central tendency
- Variability
Frequency
the number of observations that fall within category or range of scores
Central tendency
measurements
normal distribution
skewed
measure the central point of distribution
Measurements
- Mean – average; often most meaningful
- Median – middle
- Mode – most
Normal distribution – results when mean, median, mode are the same/very similar
- Bell curve – symmetrical distribution with values clustered around a central, mean value
- Common with test grades – most common influences mean and usually “middle of pack”
Skewed data – extreme data is integrated; mean, median, and mode (not influenced) will be more separated
- Common with reaction times – a few people have extremely slow reactions
Types:
- Negative skew – lots scored high; tail moves left (towards neg numbers)
- Positive skew – lots scored low; tail moves right (towards pos numbers)
variability
degree of dispersion in distribution
Spread
- Less variable – narrow bell curve
- More variable – wider bell curve
Standard deviation – measures variability around the mean; estimates average distance from mean
- Ex. 68% scores between -1 to +1 on graph
hypothesis testing
statistical significance
effect size
statistical method; are differences among groups are meaningful
How likely is difference due to chance
- More significant difference = more likely meaningfully different
- Ex. group a is more likely meaningful; group b is less likely
Statistical significance – the means of groups are farther apart than you would expect them to be by chance alone
- Null hypothesis (H0) – no significant difference; due to chance
- Experimental hypothesis (H1) – difference is due to variable controlled by experimenter
Statistical significance threshold is often: P < .05
- Less than 5% change the results were due to chance, not to experimental manipulation
Effect size – even if we find a meaningful difference, is it a large enough difference to make it important or significant
heredity
levels of genetics
the biological process responsible for passing on traits from one generation to another
DNA
Genes
Chromosomes
DNA
Genes
Chromosomes
DNA - most basic; 4 nucleotides and sugar backbone
Genes - passed onto children
- Made of DNA segments
- Double helix shape
- Deoxyribonucleic acid & 4 nucleotides – thymine, adenine, guanine, cytosine
- Basic units of heredity
- Approx. 20,000-25,000 within us
- Guides production of proteins – where they start and end
- Proteins – make up physical structures, regulate development and physiological processes
- Can be:
Active – 6000-7000; expressed and contribute to production of proteins
Inactive – not expressed
Chromosomes – 46 (23 pairs)
- DNA wrapped around histones – lined with all the genes inherited
- Within cell nucleus
- Vary in length
- The same gene (ex. eye colour) are found on both chromosomes inherited from mother and father
homo/heterozygous
dominant vs recessive
- Homozygous – corresponding genes at the same location are the same (both recessive or both dominant)
- Heterozygous – corresponding genes at the same location are different (one dominant and one recessive)
- Trait expressed is dependent on combination of gene pairs
(dominant vs recessive)
geno vs phenotype
Genotype – genetic makeup of an organism
o unique set of genes that comprise genetic code passed down from parents
o predicts phenotype
Phenotype – physical and behavioural traits expressed
o genetic variation (eye colour, facial features, intelligence, personality)
o tell us genotype
behavioural genomics & human genome project
study of DNA; exploration of genotype/genes and cause for behaviour
Human genome project – coordinated effort to identify and map the entire human genome
o 2003 – approx. 22,300 genes (sequences of DNA) were identified
o Identified patterns between characteristics among people and compared with genetic makeup
(Did not take into account nurture/environment)
behavioural genetics & heritability
how genes and environment influence behaviour (nature and nurture)
Heritability – how much genetic differences between individuals contribute to differences in behaviour, or specific traits within a population
- Can vary across cultures
Ex. in Canada is 75%, same trait in different culture is different percentage
Statistic (H2) – ranging from 0 to 1
H2 = 0: Genes do not contribute to trait differences
H2 = 1: Genes account for all individual trait differences
Estimates are effected by genetic and environmental variability – 100% is very unlikely
How genes explain differences in expression of trait – not how gene contributes to trait itself
- Eye colour: H2 = .8
- Having eyes: H2 = 0
twin studies and adoption studies in behavioural genetics
Twin studies:
Monozygotic – 1 egg; almost 100% genetically identical
- Reason that similarities will be genetically based and differences will be environmentally based
Dizygotic – 2 eggs; approx. 50% in common (same as regular siblings)
- Live together, same age, similar influences
Can compare similarities and differences in a particular trait between monozygotic and dizygotic twins to analyze genetic vs environmental influence
Adoption studies – siblings are separated (twins are especially helpful)
- Similarities due to genetics
- Differences will be largely due to environment
- Ex. the Jim twins
longitudinal studies
studying the same individuals for years
- Twin studies – how these behaviours develop
- Nature is combined with nurture influences behaviour
epigenetic & biopsychosocial model
How experiences can cause changes in gene expression without altering genetic code
- Genes can become activated later in life – influenced by genetic and environmental factors
- Feedback loop – genes dictate behaviour; behaviour will place you in a certain environment; will cause genes to be activated
Biopsychosocial – interactions (social) with environment can cause genes to become activated (bio), changing behaviour (psych)
o Ex. schizophrenia – can have gene and become activated later in life if large enough stress occurs in mid 20s (ish)
o Ex. Alzheimer’s and Parkinson’s
altering gene and expression
CRISPR-Cas9 – technique that allows genetic material to be removed, added, or altered in specific location on genome
o Genes can be repaired
o Bacteria does this in response to attacking viruses
o Ethical concerns?
evolutionary behaviour:
natural selection
evolution
evolutionary psych
Natural selection – favourable traits for survival become more common (survivors reproduce)
Evolution – change in frequency of genes occurring in interbreeding population over generations
o Not continuous – if species is well adapted currently
o Never finished – environment will always be changing
o Alfred Russell Wallace (1823-1913)
Evolutionary psych – attempts to explain human behaviour based on the beneficial functions that may have served species development
o Caution – has been used to justify gender norms
endocrine system
function hormones important glands
glands that produce and release hormones
Hormones – chemicals; slower reaction that nt/nervous system
o Secreted into bloodstream; travels throughout body
o Functions in homeostasis – energy, metabolism, body temp
Hypothalamus – brain structure; regulates basic biological and motivational systems; homeostasis
Pituitary gland – master gland; receives input from hypothalamus
o Produces hormones and stimulates other glands to release hormones (ex. adrenal gland release cortisol/stress hormone and epinephrine)
o Produces endorphins – pain reduction, feelings of pleasure (created and regulated by pituitary)
o Produces testosterone
nervous system
communication
nerves
why is understanding important
Neuronal communication – immediate response and communication through the body; system of nerves
Nerves – bundle of axons of neurons running through brain
- Involved in coordination of behaviour
Understanding helps treat mental and nervous conditions
neurons
cells responsible for sending and receiving messages throughout the body; communicate to allow us to, think, move, exist
o Cell body/soma – contains nucleus; houses genetic material
o Dendrites – receive messages; on cell body
o Axon – transports info as electrochemical reactions from cell body to axon terminal
- Myelin – creates nodes of Ranvier; propagation is faster; protective cover
o Axon terminal – bulbs at the end of axons; many branches on one; contain neurotransmitters
types of neurons
o Sensory – sends sensory info to brain
o Motor – brain to muscles/effectors
o Interneurons – communicate between neurons; important for reflexes
neurogenesis
neuroplasticity
- formation of new neurons
- Used to believe you had all neurons at birth
- brain changes and rewires based on experience
- Used to believe connections were present at birth and never changed
glial cells
Involved in
- Immune response in brain
- Removing waste
- Synchronizing neuron activity
Functions in myelin formation – fatty covering insulating axon; increases speed and efficiency of neural communication
- Multiple sclerosis – difficulty forming myelin
Outnumber neurons 10:1 in brain
reflexes
outside conscious control
o Sensory info goes to spinal cord; communicates directly with motor neurons (may include interneurons)
o Doesn’t go to brain – brain becomes aware of action later
excitation of neurons
Resting state – cell is not transmitting signals
- Na+ is higher outside cell – neg charge inside cell (RMP = -70mV)
Action potentials – wave of electrical activity starting at beginning of axon (hillock); positive charge moves down axon (insulated by myelin)
- Multiple input and output sources – messages are often needed to create graded potential that reaches threshold
- Creates feedback loop – messages are sent back to initial to continue or inhibit propagation
Occurs due to:
- Tendency for ions to move down concentration gradient
- Ion channels – pores that allow ions to pass through
Stimulation – ion channels open; Na+ rushes in; RMP becomes pos; threshold results in AP
- Na+ channels open – pos charge moves in until peak voltage
- Na+ close, K+ opens – hyperpolarizes to -90
- Refractory period – occurs after AP during hyperpolarization; neurons can’t fire until RMP is reached again
chemical synapses
- synapse
- nt (types, after release)
Synapse – area with pre synaptic axon terminal and post synaptic dendrites; separated by synaptic cleft
Electrochemical relationship – voltage change via chemical excitation (nt)
Neurotransmitters – chemical messengers; stored in vesicles
- Regulate activation and communication – do not cause (brain is responsible for behaviour by controlling how neurons are fired)
- Types
• Excitatory – makes more pos
• Inhibitory – makes more neg
- Lock and key – each nt activates particular ion channel via particular receptor
- After release, either:
• Broken down by enzymes
• Reuptake into axon terminals of presynaptic neurons (Reuptake inhibitors – block action of reuptake; used by some drugs to allow message to be continually sent)
common nt
different nt involved in different processes
Glutamine – excitatory; memory and autonomic NS reactions; how we learn, develop habits and build loops
GABA – inhibitory; lowers arousal, anxiety, excitation; allows sleep and lowers attention
- Necessary function – too excited is not a healthy function
Acetylcholine – movement and attention; joints and skeletal muscle; very common
Dopamine – controls movement through reward seeking behaviour; cognition and attention
- Ex. drinking water to feel refreshed
Norepinephrine – memory; attention to new/important stimuli; regulation of sleep and mood
Serotonin – regulation of sleep, appetite, mood
- In many prescriptions to treat depression
drug effects on nt
Agonist – enhance or mimic effect
• Ex. nicotine – acetylcholine agonist (muscle spasms)
• Ex. Xanax – GABA agonist (lowers arousal and anxiety)
Antagonist – inhibits by blocking or preventing
Both occur directly or indirectly
• Direct – binds to receptor and sends same message
• Indirect – makes the nt work more and faster
peripheral NS (2 branches and functions)
transmits signal from brain to rest of body (mainly via spinal cord)
Somatic
o nerves that control skeletal muscle; voluntary and reflexive
o receive sensory info
o ex. somatic dancing – feel of body (muscles) in different positions
Autonomic – “automatic”; controls smooth muscle, cardiac muscle, glands; we are not aware of
o Sympathetic – fight or flight (Evolutionary adaption – assisted in survival)
- Now – different stressors still activate SNS (ex. exams)
- Ex. increases blood flow to skeletal muscle; increased HR; slows digestion
o Parasympathetic – rest and digest; maintains homeostasis; returns body to non-emergency state
- Ex. increased digestion, slows HR (75bpm); pupil constriction
o Most organs are innervated by both – cause different reactions
Central NS
spinal cord function
brain & spinal cord
spinal cord - column of vertebrae; majority of axons are groups and run down, exiting at different vertebrae
o Damage can result in paralysis
2 brain hemispheres and functions
how are they connected
connected and communicate via corpus callosum
Right – cognitive tasks; visual stimuli and spatial skills; musical processing
Left – language and math
Structures often have 1 on each side (ex. amygdala)
Interconnected
• Not completely separate – but there is more opportunity for one side to be more active doing a specific activity
• Must consider network of structures – do not work alone
Ex. math – “left”; also requires visual and spatial skills
hindbrain (3 part)
life-sustaining functions for survival
Brainstem
• Medulla – breathing; HR
• Pons – wakefulness
Reticular formation – attention and alertess
• Runs from midbrain to medulla
• Damage – comatose
Cerebellum – coordinates timing/movement/balance/attention/emotional response
• Many connections and coordination between newer and older (evolutionary speaking) brain structures - Connections between midbrain and forebrain
midbrain (2 parts)
relay station between sensory and motor areas; organizes and coordinates between body and brain
Superior colliculus – visual attention
Inferior colliculus – auditory attention
forebrain (6 parts)
processing memory, emotion, thinking, reasoning; “higher functions” lead to evolutionary success
Ventricles – hollow spaces containing CSF
• Cerebrospinal fluid – provides nutrients; removes waste
• Hydrocephalus – buildup of fluid; leak or swelling of ventricles
Basal ganglia – bundle of cell bodies densely packed
• Planned movement, skill learning
• Integrates sensory and motor info with reward/pleasure system (involves pleasure nt)
• Movement disorders:
Parkinson’s – trouble with purposeful movement; reward system not functioning properly; difficulty initiating behaviour
Huntington’s – uncontrollable movement
Tourette’s – tics and uncontrollable movement
Amygdala – bottom of ventricles; part of limbic system
• Memory formation for emotional events – good or bad (PTSD)
• Mediates fear response
• Recognizing and interpreting emotional stimuli
Hippocampus – close to amygdala (work together)
• Learning and formation of new memories – spatial memories (getting from point A to B)
• (getting around campus)
Hypothalamus – below (hypo) thalamus
• Homeostasis – temp, hunger, thirst, sex
Thalamus – relays sensory info to different brain regions
• Ex. hearing to auditory cortex; vision to visual cortex (you don’t hear colour)
cortex function and location
part of forebrain; outer layer of brain (wrinkles – evolutionary adaption to create more surface)
Higher function – thought, language, personality
Consists of grey matter – cell bodies and dendrites
grey vs white matter
grey matter – cell bodies and dendrites
White matter – axons spreading to brain and body regions
4 lobes of cortex (subparts of each)
Occipital lobe – visual cortex
Parietal lobes – touch, bodily and spatial awareness, attention
o Somatosensory cortex – front of parietal; post central gyrus/sensory area
Temporal lobes – language, hearing, visual recognition (ex. someone’s face)
Frontal – higher, cognitive function; movement:
o Primary motor cortex – anterior to central sulcus (back of frontal); Execution and control of voluntary movement
o Prefrontal cortex – anterior to motor cortex; higher order executive functioning – decision making, planning movement, attention, regulation of impulse and emotion, personality, language production
o Phineas gage – railway spike; indecisiveness delineated frontal is involved in decision making
mass vs function in brain
Larger area designated to specific function – associated with requirement for complex mvmt
• Hands and mouth – large areas
• Applies to motor and somatosensory cortex
brain lesioning
and ex
Intentionally damaging area in the brain of an animal
Allows research to isolate particular brain structure, lesion, and study resulting behaviour
o Can test what parts of brain are associated with certain behaviour
o Sham group – animals that undergo same experimental procedures, except for lesion
(Controls for effects of stress, anesthesia, stiches)
Brain research stemmed from brain injury and subsequent change in behaviour (ex. Phineas Gage)
o Requires brain injuries
Ex. Morris water maze
- Measured spatial learning and navigation in rats
- Put rats in bath with platform – marked platform with visual stimulus – rats associated visual stimulus with platform
- Lesioning hippocampus – rats were unable to associate visual stimulus with platform
- Concluded hippocampus was involved in spatial navigation
brain stimulation techniques (1)
Transcranial magnetic stimulation (TMS)
a. Applying electromagnetic pulse to targeted brain region – disrupts natural brain activity and flow of ions
- Positive ions are disrupted – axons can’t function
b. Induces temporary lesion – neurons resume normal activity after pulse
c. Can stimulate and increase brain activity – applying a weaker pulse
- Research in treating clinical disorders (ex. depression)
d. Cons
- Doesn’t give you image of regions – prior knowledge is required to know where to stimulate
Structural neuroimaging techniques (3)
pictures of brain; able to see structural abnormality & physical brain damage
- Computerized tomography (CT scan)
a. X-rays sent through brain by tube that rotates around head
- Shows difference in tissue density
- Grey matter – cell bodies; denser
- White matter – axons and tracts
- Ventricles – fluid
b. Pictures create 3D imaging – ex. tumor; swelling of ventricle
2. Magnetic resonance imaging (MRI)
a. Images created based on how regions/cells absorb and release energy
- Magnetic field causes protons from hydrogen to spin in same direction
- Radio wave pulse knocks atoms out of alignment
- When radio wave is turned off, atoms return to alignment – releases energy
- Magnetic field still being applied
b. Different densities release energy at different rates – measured and creates image
- Grey matter, white matter, ventricles, tumors, swelling
- Diffusion tensor imaging (DTI)
a. Measuring connections and white matter pathways (axons) – not specific brain structures
- Shows cause of injury if damage is in communication
b. Measures water molecules in axons – molecules have different shapes/orientations that indicate direction of pathway
functional neuroimaging techniques (4)
2 considerations
activity of brain at a particular time during particular behaviour/in response to stimuli
2 considerations
o Temporal resolution – accurate time period for measuring reaction/behaviour
o Spatial resolution – how clear the image of the brain is
- Electroencephalogram (EEG) – electrical activity
a. Measures patterns of brain activity/neuronal firing using electrodes on scalp
b. Event related potential (ERP) – used to match stimuli and brain activation
c. Pros
- Good temporal – every millisecond
- Good for general areas
- Inexpensive
d. Cons
- Limited spatial resolution – does not give visual of specific area of brain activity (uses chart)
- Magnetoencephalography (MEG) – magnetic fields created by electrical activity of nerve cells in brain
a. Pros
- Good temporal – every millisecond
b. Cons
- Limited spatial – better than EEG; slightly better at localizing activity; does not give picture of individual brain structures
- Positron emission tomography (PET scan) – tracing substances in brain
a. Radioactive isotope injected in blood – measures flow of blood to particular region (more blood flow = more activity)
- Measures radiation in body and brain regions – higher radioactivity in active areas
- Allows for measurement of neurotransmitter receptors
- Ex. dopamine – which areas of brain have increased dopamine receptors; related to what that area of brain is responsible for
b. Pros
- Good spatial – visual images (not as good as fMRI)
- Measures neurotransmitter activity
c. Cons
- Poor temporal - >2 min; difficult to make absolute conclusions
- Injecting radioactive substance
- Expensive
- Functional magnetic resonance imaging (fMRI) – measures oxygen/blood flow
a. Still applying magnetic field & radio wave
b. O2 rich and o2 poor blood will have different densities
- O2 rich blood will flow to highly active areas (highly active areas will be o2 poor) – we can see what areas have been recently active
- BOLD (blood oxygen level dependant) – response from body
c. Pros
- Good spatial – better than PET
d. Cons
- Limited temporal – approx. 2 sec; a lot of activity occurs every millisecond; better than PET
(Not as good as EEG or MEG)
Anything with magnetic imaging – cannot have metals present
o Non-magnetic is helpful (ex. EEG within fMRI)
sensation
transduction
perception
sensory adaptation
orienting response
Sensation -> transduction -> perception
Sensation – the process of detecting external events with sense organs; turning stimuli into neural signals
- Specific sensory organs capture specific stimuli and send signals to specific area
- Ex. air pressure (auditory cortex) & light stimulus (visual cortex)
- Sensory adaption – the reduction of activity in sense receptors after repeated exposure (Evolutionary adaption)
Transduction – turning physical energy (light/sound waves; molecules in food/air) into electrical impulses; occurs in sensory organs, facilitated via sensory receptors
- Forms internal representation – how we process info about external world
Perception – directing attention toward, organizing, and interpreting stimuli (occurs after sensation) in brain
- Optical illusions – sensory info does not change; our perception sees what the brain tells us to see
- Orienting response – sensitive to changes in stimulus; shift in attention towards new or changed stimuli (Evolutionary adaption)
Johannes Muller
doctrine of specific nerve energies (1826)
o Different senses are process in separate areas in brain
o Separated pathway become more distinct as children mature (pathways are not initially separated)
o We learn perception through experience
psychophysics
absolute threshold
difference threshold & webers law
explores how changes in physical energy is related to psychological experience/perception
Absolute threshold – minimum amount of energy/quantity of stimulus required to be detected 50% of time (from nothing); varies across individuals
o Ex. hearing a beep
Difference threshold/Just noticeable difference – smallest difference between stimuli that can be detected 50% of time (from something to something); varies across individuals
o Ex. hearing the change in volume of beep; 2-point touch discrimination
o Dependant on intensity of original stimulus – more intense initial stimulus will require larger change to detect difference
Ex. Gustav Fechner – 5lb and 1lb weight; ¼lb added to 1lb was more noticeable
Weber’s Law – the JND between 2 stimuli changes as a proportion of stimuli; change in initial stimuli is proportional to change required to detect difference (initial stimulus doubles, JND will double)
2 things determine sensory experience
o Sensory – presentation of stimulus
o Decision – deciding whether stimulus was detected
stimuli detection is influenced by
o Individual’s sensory organs – impairment and acuity
o Expectations – you will detect a change if you expect one
o Motivations – are you motivated to detect a change
priming
previous exposure to stimulus can influences later response to stimulus or related stimulus (subliminal perception)
o Ex. spending a lot of time with ducks – will see ducks in duck/bunny illusion
o Ex. mail is delivered at 11 – you expect it
Gestault psych
the whole is greater than sum of its parts (part of cognitive revolution); individual pieces of sensory inputs are organized and combined to create whole perception
Ex. negative spaces – proximity, similarity, continuity, closure
how attention effects perception
- Divided attention – directed to more than one stimulus/task at once
- Selective attention – focusing on particular task/event (ex. noticing all the blue suburus after buying one)
- Inattentional blindness – failing to notice event because attention is elsewhere (ex. magic tricks)
haptics
transmitting and understanding information through touch and proprioceptors (touching to get info)
o Active & exploratory – sliding hand over surface gives more info than simply touching
o Different sensitivity in different parts of body
Hands, face, lips, ears – many receptors; highly sensitive
Legs, back, knees, arms – less receptors; low sensitivity
kinesthesis
proprioception; receptors in muscles, joints, tendons transmit info about movement and position
nociception
gate control theory
phantom limb
pain receptors; nerves involved in discomfort (ex. sharp, burns)
Cognitive, sensory, and emotional factors interact to influence nociception/perception of pain (emotional pain causes increased physical pain)
Gate control theory of pain – interacting nerves that results in inhibiting pain receptors (closes gate)
- Stimulation of larger touch receptors/nerve tracts inhibit smaller nociceptor tracts (ex. rubbing area; applying ice/pressure)
Phantom limb pain – feeling painful sensation from absent limb; itching, contraction, discomfort
- Caused by hypersensitive nerve cells that used to be connected to missing limb; firing inappropriately
- Treatment – mirror boxes & virtual reality; stimulating the brain to view limb as present alleviates some pain
2 chemical senses and why are they chemical senses
taste & smell
Transduction – molecules/chemicals are converted to electrical signal
gustatory system
2 components
parts of brain sent to
Taste – perception
o Primary tastes – salt, sweet, bitter, sour, umami (savory)
Tongue – sensory organ
o Sensory receptors – 9000 taste buds/gustatory cells within papillae (bumps on tongue)
- Transduction occurs
- Certain molecules activate different cells
- Blind spot in middle of tongue – few receptors
- Replaced every 10 days approx.
o Neurons transmit to
- Gustatory cortex - perception of taste
- Secondary gustatory cortex – pleasurable experiences associated with food
olfactory system
Smell – detection of airborne particles via cilia cells (sensory receptors) lining the olfactory epithelium within nasal cavity
Longer hair in nose prevent unwanted material
Approx. 1000 odour receptors – can identify 10,000 smells
- Experience of smell is produced by pattern of receptor stimulation – creates complex and diverse stimuli
Transmits to olfactory bulb (skips thalamus) – region for processing smells at base of frontal lobes
- Connected to other brain regions via olfactory tract – processing emotion and subjective experience (pleasure vs disgust)
Cilia of olfactory epithelium -> olfactory bulb -> olfactory tract -> other brain regions (higher processing)
sound waves
changes in mechanical pressure through a medium (usually air)
Frequency – wavelength; pitch:
- Measured in Hz (cycles per second)
• Shorter wavelengths = higher frequency
- Pitch – perceptual experience of soundwaves
• High pitch = short wavelengths/high frequency
• Low pitch = long wavelengths/low frequency
- Humans can detect 20 Hz – 20,000 Hz (20,000 cycles/sec)
Amplitude – height of wave; loudness - Measured in Db (decibels) • Higher amplitude = louder • Lower amplitude = quieter - Humans can detect above 20 Db
3 sections of ear and components
Outer ear
- Pinna – shaped to capture sound waves
- Auditory canal – soundwaves travel through; Causes eardrum to vibrate – membrane at the end of auditory canal
Middle ear Ossicles: • Malleus (hammer) • Incus (anvil) • Stapes (stirrup) Oval window – moves in response to vibrations in ossicles
Inner ear
Cochlea – fluid filled membrane; coiled
• Basilar membrane – hair cells are stimulated in response to fluid movement
• Hair cells (receptor cells) – stimulate auditory nerve cells
• Auditory nerve cells – transduction; auditory nerve -> thalamus
localization of sound
brain stem and inferior colliculus (midbrain)
Compares timing and intensity in each ear
pitch (3 theories)
Place theory of hearing – location of hair cell stimulation
• Closer to ossicles – higher frequency (cannot travel as far)
• Farther from ossicles – lower frequency
Frequency theory – perception is related to frequency at which basilar membrane vibrates
• How many times hair cells are stimulated (high frequency – waves hit more often)
Volley principle – group of neurons fire at staggered/alternating pace; increases level of frequency we perceive (firing is limited due to refractory period)
2 cortex for hearing
temporal lobe from thalamus
o Primary auditory cortex – sound processing and perception; organized into sections by frequencies/pitches
o Secondary auditory cortex – interpreting complex sounds (speech and music)
vestibular system (3 main components)
sensory system in inner ear that provides info about spatial orientation/motion of head
Vestibular sacs – detect if head is no longer in upright position; important in navigating environment and orientation
- Utricle & saccule – filled with fluid
- Cilia (receptors) at the bottom of sac -> bends in response to fluid -> message to brainstem
Semicircular canals – 3 canals in inner ear; respond to head movement (up/down; left/right; forward/backward)
- Ampulla – enlarged area at base; contain cilia in fluid
- Bend in response to fluid -> message to brainstem
Vestibular ganglion/nerve tract – transmits info to brainstem; influences processes and behaviours
- Autonomic NS response – involuntary response
- Amygdala – emotional response (panicky when slipping)
- Insula – integrates visual, somatosensory, and vestibular info (conflicting inputs can cause motion sickness)
light wavelengths
colours – wavelength
- long – reddish
- medium – greenish
- short – blueish
brightness – amplitude
- low amplitude – dim
- high amplitude – bright
components of eye and function
- corneas – protects eye and bends light
- pupil – hole; light enters through
- iris – muscle around pupil; regulates amount of light entering (PSNS)
- lens – changes shape to bend light and focus light on retina (accommodation)
- retina – photoreceptors at the back of the eye; coverts light to neural signals (transduction)
o cones – colour; high acuity; requires more light
o rods – no colour; low acuity; sensitive under low light - ganglion cells – receive signals from photoreceptors (rods/cones)
o send signals optic nerve -> brain - blind spot – nerve forms and exits eye; brain corrects for this and you perceive vision
- fovea – central region of retina; image is focussed directly here (highest acuity)
o densely packed cones; surrounded by rods
o peripheral vision – outside fovea; blurrier
2 colour perception theories
subjective experience occurs in brain
trichromatic theory/young-Helmholtz theory – vision from activity of individual cones
- 3 types of cones
1. Red sensitive cones (long)
2. Green sensitive cones (medium)
3. Blue sensitive cones (short) - Combine to create experience of colour (ex. teal – blue and green cones)
Opponent processing theory – higher level; vision from combination of cone activity; opposition/conflict
- One is inhibited when we view the other – 2 sources of info (stimulation and inhibition); “backup” mechanism
1. Red vs green
2. Yellow vs blue
3. White vs black - Pattern of cell activity – allows greater intake of information (not singularly/one at a time)
- Organized by ganglion cells – process signals from multiple cones
Complimentary processes/theories
visual disorders
Colour blindness – achromatopsia (no colour; rarer)
o Colour deficiency – one of three cones can’t pick up wavelengths; reliant on other 2 (more common)
Ex. red-green colorblindness
Nearsightedness/myopia – image is being focussed too close to lens
o Can also occur from misshaped eyeball
Farsightedness/hyperopia – image is focussed too far behind retina
o Can also occur from misshapen eyeball
visual cortex and cross over
Visual cortex – occipital lobe
Optic chasm – cross over of optic nerve occurs
- Right visual field – processed on left side of eye/left visual cortex
- Left vision field – processed on right side of eye/right visual cortex
detection and simple cells
Detection cells – respond to specific, simple aspect of visual stimulus
- Discovered by Hubel & Wiesel (1959) – tests showed firing of neurons from specific stimuli
- type of simple cell – brain combines figures perceived by cells
- Horizontal & vertical
- Cells fire most when shown straight vertical/horizontal lines; fire less when lines are slanted
ventral stream
(downwards)
Object recognition – integrated individual features into neural representation (categorical organization)
Perceptual constancy – perceive objects as the same shape/size/colour despite changes in perspective
- Expectation – causes us to see a particular thing
- Ex. blue/black or white/gold dress – expectations about lighting perceive different colours schemes
dorsal stream
(upwards)
Acts on stimulus from ventral stream
- Where pathway – Ungerleider & Mishkin (1982)
- Visually guided action – Milner & Goodale (1992); reaching and grasping
Patient DF – damaged ventral stream
- Impaired object recognition; preserved visually guided action
depth perception (2 types)
- Binocular depth cues – distance based on differing perspective from both eyes
Convergence – contraction of eye muscles; both focus on single object
- Move together when object is close
- Straighten out when object is far
Retinal (binocular) disparity – difference in relative position of an object as seen by both eyes
- Monocular depth cues – can perceive with only one eye (not as good)
Accommodation – bending of lens to focus image
- information on change in shape to view distance of object is sent to brain
Motion parallax – close objects appear faster moving; far objects move slow
- brain receives info by how fast object moves
multimodal integration
& synethesia
ability to combine sensation from different modalities into a single. Integrated perception; experience is created by a combination of senses
sensation that occur together will likely be combined (ex. animals with their sound)
o McGurk effect – when visual and auditory info is combine, we can trick brain into hearing something by seeing something
combining visual and auditory stimuli in conversation
o facial expression, tone, body language
synesthesia – unexpected integration of multiple senses; blended experience
o ex. hearing colours; seeing sounds
