Psych 104

Chapter 1

Module 1.1

• Establish foundation

• Human Psychology - scientific study of behaviour and mental processes, broken down into different sections. 

• Find observation and opinion, then find ways to prove that observation = science of psychology

• Four goals of psychology:

• Description: make notes about behaviours or situations, which become data, important in early stages of research

• Explanation: requires understanding of conditions and causes of  behaviour and mental processes

• Prediction: specify conditions under which behaviour or event will likely occur, understand and predict likelihood of occurrence

• Influence: apply principle and change conditions to prevent unwanted occurrences, bring about desired outcomes.

• Theory: general principle or set of principles to explain the relationship between a number of separate facts.

• Allows us to organize facts systematically

• Guides scientific research to validate theory

• Basic Research

• Seeks new knowledge

• Explores, advances general scientific understanding

• Answers description, explanation, and prediction

• Applied Research

• Applying research to life

• Solving practical problems

• Improving quality of life

• Answers influence

• Trying to change certain outcomes

Module 1.2

• Descriptive Research Methods:

• Naturalistic observation: most basic type. Observe and record behaviour in natural setting, no attempt to influence or control behaviour

Advantage: study behaviour in natural setting 

Disadvantage: time consuming, observer bias can distort observations

• Laboratory observation: similar to above,  researchers can exert more control over the environment

Advantages: more control over environment and more precise equipment to measure responses 

Disadvantages: less spontaneity of behaviour

• Case study method: one or few participants are studied in depth usually over an extended period of time, study uncommon psychological/physiological disorders, provide detailed accounts, use observation, interviews, psychological testing.

Advantages: in depth, detailed analysis of cases

Disadvantages: can’t establish cause of observed behaviours, hard to generalize results

• Survey research: use interviews and questionnaires to obtain information about attitudes, beliefs, experiences of a group.

Population - sample - representative sample

Advantages: can use large numbers of people, show changes in attitudes and behaviour over time

Disadvantages: can be costly and time-consuming, need expertise, respondents may provide inaccurate information

• Correlational Method: establish relationship (correlation) between two characteristics, events, or behaviours. Useful in making predictions, cannot determine cause.

Correlation Coefficient: numerical value, indicates strength and direction of relationship between two variables. Relationship, not a causation (exams and stress). If both arrows are going the same direction, perfect positive correlation (+1.00). If arrows are going opposite directions, perfect negative correlation (-1.00). 

Correlation and Prediction: stronger relationship = better prediction. Correlation does not equal cause. Used because it is sometimes unethical to study variables more directly and many variables cannot be manipulated.

Figure 1.1

Module 1.3

• Experimental method - only research method to identify cause-effect relationships

• Test hypothesis (educated guess)

• Cause-effect relationship between two or more variables.

• Ex: what is the effect of multitasking during a lecture?

Advantages:

• Reveal cause-effect relationships

• Control over experimental setting

        Disadvantages:

• Less generalizable findings unless using field studies

• Ethical limitations of experiments

• Independent variable (IV): (treatment) manipulated to determine if causing change in behaviour or condition, x-axis

• Dependent variable (DV): measured at end of experiment, varies if IV manipulated, y-axis

Figure 1.2

• Experimental group: participants exposed to IV

• Control group: exposed to same experimental environment, not given treatment, used for comparison

• Rule out chance of other factors

• Controlled setting in laboratory

• Conclude that manipulation of IV causes differences among the groups

• Generalizing experimental findings: do the findings apply to other groups?

• To generalize results researchers must replicate/repeat the experiment

• If the experiment uses a very small or limited group then findings cannot be generalized to the larger population

• Selection bias: systematic differences among groups present at beginning of experiment, may be due to pre-existing differences in groups, use random assignment to help.

• Random assignment: assign participants to control or experimental group by chance

• Be aware of your bias

• Placebo effect: a person’s response to the treatment is due to the expectations rather than the treatment itself

• Placebo: inert substance (sugar pill, saline solution), can be given to control group

• Experimental bias: preconceived expectations influence participants behavior or interpretation of results

• Double-blind technique: unknown who is in treatment or control group, counteract/combat experimental bias

(recap video on independent and dependent variables,link on D2L)

• Make independent variable separate from other possible variables, and the rest are therefore “constant”

Module 1.4

• Research issues

• Avoid ageism, sexism, cultural bias

• Human participants; use of students(as long as it makes sense for what you are trying to conduct); generalizing results

• Psychological tests; reliability and validity

• Ethical guidelines in research (humans and animals)

• Ethics in research: Canadian Psychological Association guidelines:

• Participation must be voluntary/confidential/may withdraw at anytime

• Must be debriefed about full purpose of study and implications

• Research involving Indigenous people must involve them in the design and execution of the research in order to respect their unique cultural perspectives

• Accommodate for differences in cultures

• Use of deception justified if:

1. Value of potential findings

2. Disclosure would influence response

3. Information about risks not withheld

4. Participants debriefed asap

(consider Milgram’s study of obedience, broke guidelines)

• Use of animals in research:

1. Simpler model of processes

2. More control over animal subjects

3. Wider range of medical and other manipulations can be used

4. Can study lifespan and multiple generations in some species

5. Cheaper, convenient for research

• Bound by Canadian Code of Ethics for Psychologists

• Guidelines of Canadian Council on Animal Care

• Animal research supported only when reasonable expectation that valuable knowledge will be obtained.

Module 1.5

• Wilhelm Wundt:

• Founder of psychology as academic discipline

• Psychological lab in Liepzig, Germany, 1879

• Subject matter, conscious experiences of individuals

• Searching for structure of conscious experience

• Reason that psychology is a separate discipline

• Edward Bradford Titchener:

• Introduced psychology to North America

• Structuralism

• Analyze basic elements/structure of conscious mental experience

• Introspection method of self-observation seen as not objective

• Functionalism:

• Mental processes help animals adapt to environment

• Strong impact from Charles Darwin (On the Origin of Species by Natural Selection)

• Broadened scope of psychology to include study of behaviour and mental processes

• Gestalt Psychology:

• Perceived whole is more than sum of its parts

• Leader was Max Werthheimer who introduced famous experiment demonstrating phi phenomenon

• Gestalt principles influence psychology of perception today

• Behaviourism: founded by John B. Watson

• Observable, measurable behavior

• Environmental factors determine behaviour

• B.F. Skinner - operant or deliberate conditioning

• Criticism: ignores mental processes, thoughts, feelings

• Psychoanalysis: Sigmund Freud

• Unseen, unconscious mental forces key to understanding human behaviour

• Psychoanalysis and iceberg analogy

• Controversy: emphasis on sexual and aggressive impulses

• Humanistic Psychology:

• Uniqueness, choice, growth, psychological health, innate goodness, free will

• Abraham Maslow’s hierarchy of needs and self-actualization (humanity lies mostly in psychological needs)

• Carl Roger’s person-centered therapy

• Let them lead

• Cognitive Psychology:

• Mental processes: memory, problem solving, concept formation, reasoning, decision making, language

• Humans are active in cognition

• Parallel processing: management of multiple bits of information processing

• PET scans can observe brain cells carrying out mental processes

Module 1.6

• Biological perspective

• Brain and central nervous system, neurons, neurotransmitters, hormones, genes

• Neuroscience: study of brain functioning

• Behavioural and cognitive neuroscience subfields

• Evolutionary perspective

• Humans adapted and evolved to survive

• Adaptation of the mind has not progressed at same pace as social circumstances

• Evolutionary principles common to all humans

• Sociocultural perspective

• Social and cultural influences on human behaviour

• Importance of understanding influences when interpreting behaviour of others

• Need cultural sensitivity in research

• Biosocial perspective

• Relatively new model

• Considers physica;/mental health as the outcomes 0f the intersection of an number of factors

• Include genetic predisposition, psychological makeup, and social relationships

• Psychologists at work:

• Clinical psychology

• Counselling psychology

• School and educational psychology

• Applied psychology (forensics, health, sports, industrial/organizational)

Figure 1.4

Chapter 2

Module 2.1

• Neurons

• Afferent (sensory) neurons:  relay messages from sense organs, receptors to brain or spinal cord

• Efferent (motor) neurons:  signals from brain, spinal cord to glands, muscles; movement

• Interneurons: thousands of times more numerous than sensory/motor neurons, carry information between neurons in brain and neurons in spinal cord

• Parts of a neuron:

• Cell body: contains the nucleus, carries out metabolic functions

• Dendrites: branch-like extensions of neuron, receive signals from other neurons

• Axon: slender, tail-like extension of neuron with many branches which all end in axon terminals, transmits signals to dendrites or cell body of other neurons and to muscles, glands, other parts of body, some are tiny while others may be up to a meter long

Figure 2.1

• Supporting the neurons:

Glial Cells:

• Hold neurons together

• Remove waste products (dead neurons); handle metabolic tasks

• Make myelin for cell transmission tasks (pain transmission)

• The Synapse

Synaptic clefts:

• Neurons are not physically connected

• Space between axon terminals are small gaps filled with fluid

  Synapse:

• Axon terminal of sending neuron communicates with receiving neuron across synaptic cleft

• Neural impulse:

Resting potential

• Neuron is at rest (not firing)

• Inside axon normally more negative than positive ions

• At rest, neuron carries negative electrical potential (charge) compared to fluid outside cell

Action potential

• Neuron is stimulated; positive ions flow into axon

• Membrane potential changes to positive value

• Sudden, brief reversal is called action potential

• All or none law (neuron fires or does not)

• Myelin sheath: white, fatty coating around some axons

• Impulses up to 100 times faster along axons with myelin sheaths

Figure 2.2

• Neurotransmitters:

Chemical Messengers

• Neurons use chemical substances called neurotransmitters to communicate with one another

• Receptor sites at the axon terminal bind and take up the neurotransmitter molecules into the synaptic cleft

Receptor sites

• Each neurotransmitter molecule has a special shape that only fits the receptor of the same shape

• Similar to a lock and key fitting together

Reuptake

• Neurotransmitters taken from synaptic cleft into axon terminal

Figure 2.3

• Types of neurotransmitters:

Acetylcholine(ACh)

• Excitatory or inhibitory

• Excites skeletal muscle fibres

• Inhibits heart muscle figures

• Excites neurons involved in learning new information

Dopamine (D A), monoamine

• Excitatory and inhibitory

• Learning, attention, movement, reinforcement

• Ability to feel pleasure or fear

Norepinephrine (N E), noradrenaline, monoamine

• Eating habits, alertness

• Involved in mood regulation

Epinephrine (adrenalin), monoamine

• Complements N E

• Affects metabolism of glucose

Serotonin

• Inhibitory

• Mood, sleep, impulsivity aggression, appetite, depression, anxiety disorders

Glutamate (glutamic acid), amino acid

• excitatory

• Active in higher brain structures

GAB A (gamma-aminobutyric acid), amino acid

• Inhibitory

• Widely distributed throughout CN S

• Facilitates control of anxiety in humans

Endorphins

• Opiate-like substances

• Relief from pain or stress of vigorous exercise

• Produce feelings of pleasure and well-being

(video - biology of the brain overview)

Module 2.2

• Nervous system:

• Central nervous system (CN S): two parts: brain, spinal cord

• Peripheral nervous system (PN S): connects CN S to all other parts of the body

• Spinal cord

• Extension of the brain

• Connects/links body to brain

• Transmits info from brain to PN S and from PN S to brain

• Sensory info from PN S can reach brain

• Brain can send messages to muscles, glands, body parts

• “Super highway”

• Protected by bone and spinal fluid

• Can act without the brain, spinal reflex (hot stove, stub toe)

Figure 2.4

• Brainstem: begins at site where spinal cord enlarges as it enters skull. Major structures:

Medulla:

• Controls automatic functions

• Heartbeat, breathing, blood pressure, coughing, swallowing

Reticular formation (aka reticular activating system or RA S):

• Regulates arousal and attention

• Screens messages entering brain

Pons “Bridge”

• Connects left and right cerebellum

• Plays role in balance, sleep, dreaming

Midbrain

• Located above pons, processed auditory and visual information and influences motor control

Figure 2.5

• Cerebellum:

• Means “little cerebrum” or “little brain”

• Contains two hemispheres

• Executes smooth, skilled body movements

• Motor movements

• Balance

• Regulates muscle tone and posture

• Athletes and dancers have larger than those who are not

• Recent info reveals it has a role in emotional and cognitive functions (ie: working memory and emotions)

• Thalamus:

• Relay station for information flowing into and out of higher brain centres

• Learn new and verbal information

• Regulates sleep cycles, close to Pons

• A lot of it is auditory

• Hypothalamus:

• “Master regulator”

• Regulates hunger, thirst, sexual behaviour, emotional behaviours

• Regulates internal body temperature

• Regulates biological clock

• Stomach rumbling

• Throws off emotion around time of period

• Limbic System:

Amygdala

• Responses to aversive stimuli

• Learned fear responses

• Associations between external events and emotions

• emotion

Hippocampus

• LTM, navigational “maps”

• Walls in “Inside Out”

• memory

Figure 2.6

Module 2.3

Figure 2.7

• Cerebral Hemispheres:

Cerebrum

• Two cerebral hemispheres

• Connected by corpus callosum

Corpus Callosum

• Thick band of nerve fibres

• Transfer of information, coordination of activity between hemispheres

Cerebral Cortex

• Covers cerebral hemispheres

• Higher mental processes

• Language, memory, thinking

• Cortex = grey matter

Figure 2.8

• Closer you get to the front of your brain, the more complex

• Frontal Lobes: moving, speaking, thinking

Motor Cortex

• Controls voluntary body movement

• Wilder Penfield’s homunculus map

• Plasticity: can adapt to changes

• There is a cross section that if you touch or probe, a certain part of the body will react

Figure 2.9

Broca’s Area

• Located in the cerebral cortex

• Controls the movement of muscles that product speech

• Injury = Broca’s Aphasia: patients know what they want to say but cannot produce speech

Frontal Association Areas

• Thinking, motivation, future planning, impulse control, emotional responses

• Major changes in emotional responses if damaged

• Case Study: Phineas Gage - metal rod went through frontal lobe, drastically altered emotional responses

• Parietal Lobes: Touch

• Reception, processing of touch stimuli

• Lobes contain somatosensory cortex

Somatosensory Cortex

• touch, pressure, temperature, pain register in cortex

• Awareness of body movements and position

• Occipital Lobes: Sight

• Contain primary visual cortex

• Association areas involved in reception and interpretation of visual information

Primary Visual Cortex

• Area at back of occipital lobes

• Vision registers in cerebral cortex

• Temporal Lobes: Hearing

Primary Auditory Cortex

• Where hearing registers in cortex

• Injury = damage to hearing

Wernicke’s Area

• Left temporal lobe

• Comprehending spoken words

• Formulating coherent written and spoken language

• Injury = Wernicke’s Aphasia: speak fluently, content of speech vague or incomprehensible, word salad

Temporal Association areas

• House memories

• Interpretation of auditory stimuli

• Special association area where familiar melodies are stored

Module 2.4

• Cerebral Hemispheres

• Lateralization: specialization of cerebral hemisphere

Left Hemisphere:

• Language and mathematics

• Controls right side of body

• Coordinates complex movements

Right Hemisphere:

• Visual-spatial relations

• Controls left side of body

• How we “hear” language

• Creativity and intuition

• Recognizing and expressing emotion

• Split Brain:

Split-Brain Operation:

• Performed in severe cases of epilepsy

• Corpus callosum is cut, separating cerebral hemispheres

• Usually lessens severity and frequency of grand mal seizures

Testing the split brain person:

• Roger Sperry’s research

• Only verbal left hemisphere can report what it sees

• Left hemisphere does not see what is flashes to right hemisphere

• Right hemisphere is unable to report verbally what it has viewed

Figure 2.10

Module 2.5

• The Brain Across the Lifespan

• Brain grows in spurts

• Spurts in childhood/adolescence correlated with advances in physical and intellectual skills

• Brain gains and loses synapses throughout life

• Brain weight begins to decline around age 30

• Brain Damage

• Hippocampus can regenerate neurons

• Damaged neurons can sprout new dendrites

• Damaged neurons can re-establish connections with other neurons

• Can assume some functions of lose brain cells

• Axons can regenerate and grow

• Reorganization of brain = plasticity or neuroplasticity

Module 2.6

• EE G and Microelectrode

• EEG = Electroencephalogram: record of brainwave activity

• Measures 4 types of waves: beta, alpha, theta, delta

• Microelectrode: tiny wire, can be inserted into a single neuron

Figure 2.11

• Brain Waves

Beta Wave:

• 13 or more cycles per second

• Person is mentally or physically active

Alpha Wave:

• 8 to 12 cyc;es per second

• Occurs when individual is awake

• Person is deeply relaxed

Theta Wave

• Slow brain wave

• During light sleep, trances, just before deep sleep

• Just before awakening

Delta Wave

• Slowest brain wave, 1-3 cycles per second

• Slow-wave or deep sleep

• Scanning Techniques

C T Scan (Computerized axial tomography)

• Computerized cross-sectional images of brain structure

MR I (Magnetic Resonance Imaging)

• Cleaner, more detailed images of brain than CT scan

• No radiation

• Revealing what the brain looks like but cannot show what the brain is doing

PE T (Positron Emission Tomography)

• Map patterns of blood flow, oxygen and glucose use

• Show activity in specific areas of the brain

fMR I (Functional Magnetic Resonance Imaging)

• Image both structure and activity

SQUID (Superconducting Quantum Interference Device)

• Magnetic changes in electric current that neurons discharge

• Very specific to neurons

MEG (Magnetoencephalography)

• Neural activity in brain as it happens

• Usually done when trying to attach certain things on head

Module 2.7

Figure 2.12

• Peripheral Nervous System (PN S)

• Nerves connecting CN S to body

• Sends info to other parts of the body

• Receives info from other parts of the body

• Divided into Somatic and  Autonomic systems

• Somatic Nervous System (SN S)

• Voluntary muscle control

• Sense receptors to CNS

• Motor nerves, from CNS to skeletal muscles

• Autonomic Nervous System

• Automatic and involuntary

• CN S messages to glands, cardiac (heart) muscle, and smooth muscles

Sympathetic Nervous System

• Stress system

• Prepares body for action

• Fight or flight

Parasympathetic Nervous System

• Relaxation system

Figure 2.13

Module 2.8

• Endocrine System

• Series of ductless glands in body

• Manufactures, secretes hormones

Hormones

• Released in one part of body

• Affects other parts of body

• Like a neurotransmitter, but for specific functions or parts of body

• Travel through blood stream

Figure 2.14

Pituitary Gland “Master Gland”

• Controlled by hypothalamus

• Releases hormones that activate other glands

Thyroid Gland

• In front lower part of neck, below voice box

• Produces hormone thyroxine

• Causes hyperthyroidism if too much thyroxine, hypothyroidism if too little

• Regulates food metabolism

Adrenal Glands

• Two adrenal glands above kidneys

• Produces epinephrine and norepinephrine

• Activates sympathetic nervous system

• Releases corticoids to control salt balance; releases sex hormones

Sex Glands (Gonads)

• Females/ovaries; males/testes

• Activated by pituitary gland

• Release sex hormones for reproduction

Pancreas

• Regulates blood sugar levels

• Releases insulin and glucagon into bloodstream

• People with diabetes produce too little insulin to regulate blood sugars

• People with hyperglycemia produce too much insulin and have low blood sugar

Chapter 3

Module 3.1

• Sensation and Perception

Sensation

• Senses detect visual, auditory, and other sensory stimuli

• Then transmit stimuli to brain

• First point of contact when it comes to information

Perception

• Sensory information is actively organized, interpreted by brain

• After the brain has processed that information and brings into mix other experiences in the past relating to

• Absolute Threshold

• Difference between not being able to perceive stimulus and being just barely able to perceive it

• Minimum amount of sensory stimulation detected 50% of time

• Hearing music means absolute threshold has been crossed

• Difference Threshold

• Measure of smallest increase/decrease in physical stimulus required to produce JND

• JND = “just noticeable difference” = smallest sensation detected 50% of the time

• If you’re holding a 2kg weight and adding 500g, you will notice the difference. However, you will not notice the addition of 500g to a 50kg weight, because of Weber’s Law

• Weber’s Law

• Ernst Weber established Weber’s Law more than 150 years ago

• Weber’s Law states JND depends on percentage change in stimulus

• Greater original stimulus, more increase needed for JND

• Signal Detection Theory

• Detecting sensory stimulus involves noticing stimulus against background “noise” and deciding whether stimulus is actually present

• Special relevance in many occupations

• Air traffic controllers, police officers, military personnel on guard duty, medical professionals, poultry inspectors

• Experts will notice the thing they are an expert in

• Transduction and Adaptation

Sensory Receptors

• Detect, respond to one type of stimuli

Transduction

• Sensory receptors change sensory stimulation into neural impulses

Sensory Adaptation

• Become less sensitive to unchanging sensory stimulus over time

• Example: if you immerse yourself in a cold lake in the late fall, you will feel the cold initially but eventually adapt to it

Module 3.2

• Light: what we see

Photons

• Tiny light particles

• Travel in waves

• Majority of waves too long or too short for humans/animals to see

• Our eyes respond to visible spectrum

Figure 3.1

• The Eye

Cornea

• Tough, transparent, protective layer covering front of eye, bends light rays inwards, through pupil, contact lenses touch cornea

Pupil

• Small dark opening in centre of iris

Iris

• Coloured part of eye; muscles dilate and contract pupil through reflex

• Lens

• Suspended behind iris and pupil

• Composed of many thin layers

• Looks like transparent disc

• Flattens while focusing on distant objects

• Bulges in centre while focusing on close objects

• Accommodation: flattening and bulging action

Figure 3.2

• Lens to Retina

Nearsightedness (Myopia)

• Distance through eyeball too short or too long

• See nearby objects clearly, distant images blurry

Farsightedness (Hyperopia)

• Focal image longer than eye can handle

• Acts as if image should focus behind retina

• See distant objects clearly, close object blurry

Figure 3.3

• Rods and Cones

Rods

• Light sensitive receptors in retina

• Respond to black and white

• Encode in shades of grey

Cones

• Receptor cells in retina

• Help see colour and fine detail

• Don’t function in very dim light

• From Retina to Brain

Fovea

• Small area of retina, clearest point of vision

• Largest concentration of cones

• Receptors change light rays into neural impulses

• Impulses transmitted to bipolar, amacrine, horizontal cells, then ganglion cells

• Ganglion cells bundle into ‘cable’ leaving retinal wall, on way to brain

• Ganglion cells have very big part in transmission of light

• Blind spot: where cable runs through retinal wall’

• Optic nerve: after cable leaves retinal wall

• Visual Sensation to Visual Perception

Optic Chiasm

• Optic nerves from both eyes come together, nerve fibres cross to opposite sides of brain

• Helps depth perception

• After optic chiasm, optic nerve to thalamus, then primary visual cortex

• Kind of like where left and right brain come together

• Primary Visual Cortex

Feature Detectors

• Certain neurons in brain

• Responding only to specific visual patterns such as lines or angles

• Coded at birth the make unique responses

Figure 3.4

• Three Dimensions of Colour Vision

• Hue = colour we see

• Saturation = purity of colour

• Brightness = intensity of light energy we perceive

Figure 3.5

• Theories of Colour Vision

• Even though these are more obvious and easy to know for us now, we learn these to understand the foundation of the subject

Trichromatic Theory

• Three types of cones in retina

• Each type makes its maximum chemical response to blue, green, or red

• Theory consistent with what happens with cones

Opponent-Process Theory

• Three classes of cells

• Red/green, yellow/blue, black/white

• Increase/decrease firing rate when different colours present

• Kind of like a seesaw

• Only one or the other colour, not both

Negative Afterimage

• Use opponent-process pairs

• Stare at one colour; brain will give sensation of opposite colour on white surface

• Opponent-Process Theory consistent with happenings in ganglion cells

• Colour Processing

• Researchers believe colour processing starts at level of retina

• Continues through bipolar and ganglion cells

• Is completed in colour detectors in visual cortex

• Colour Blindness

• Inability to distinguish certain colours

• 8% males, 1% females

• Males: mainly problems distinguishing red from green

• Genes for colour vision are carried on X chromosome

• Males do not have the ability to see the finer detail when it comes to seeing colour

Figure 3.6

Module 3.3

• Characteristics of Sound

• Frequency (Hz): number of cycles completed by sound wave in one second, pitch of the sound

• Amplitude (dB): loudness of sound caused by force or pressure with which air molecules move, tone of the sound

• Timbre: distinct quality of sound distinguishing it from other sounds of same pitch and loudness

Figure 3.7

Figure 3.8

• Outer Ear

Pinna

• Visible curved flap of cartilage and skin, sort of scoops in air molecules

Auditory Canal

• 2.5 cm long, lined with hairs

• Leads to eardrum

Eardrum (Tympanic Membrane)

• Thin, flexible membrane

• About a centimeter in diameter

• Moves in response to sound waves

• Middle Ear

Ossicles

• Inside chambers of middle ear

• 3 smallest bones in body

• Size of grain of rice

• Hammer, anvil, stirrup, link eardrum to oval window

• Amplify sound 22 times

• Inner Ear

Cochlea

• Fluid filled, snail-shaped, bony chamber

• Stirrup pushes against oval window, vibrations move cochlear fluid in waves

• Waves ,ove basilar membrane hair cells

• Produce electrical impulse transmitted to brain

Figure 3.9

• Theories of Hearing

Place Theory

• We hear individual pitches

• Determined by place along basilar membrane of cochlea vibrating most

• Theory can’t explain how we perceive frequencies below 150 Hz

Frequency Theory

• 500 Hz tone stimulates hair cells to vibrate 500 times per second

• Theory not valid for high frequency tones

• Neurons cannot fire more than 1000 times per second

• Both place and frequency theories contribute to explaining what we hear

• Hearing Loss

Conductive Hearing Loss

• Disease or injury to eardrum or middle ear bones

• Sound waves cannot be conducted to cochlea

• Medical or surgical repair

• Hearing aid can bypass middle ear

• Uses bone conduction to reach cochlea

Sensorineural Hearing Loss

• Damage to cochlea or auditory nerve

• Hearing aids may reduce hearing loss if damage to cochlea not severe

• Hearing aids no help if damage to auditory nerve

• Hearing loss early in life from such things as loud toys and fireworks can cause issues for children

• Speech development difficulties

• Challenges in school and social relationships

Module 3.4

• Smell

Olfaction

• Sensation of smell; a chemical sense

Olfactory Epithelium

• Patch of tissue at top of each nasal cavity

• Contains 10 million smell receptor cells

Olfactory Bulbs

• Two matchstick-sized structures adobe nasal cavities

• Smell sensations first register in brain

• Messages from olfactory bulbs relayed to different parts of brain

Figure 3.10

• Pheromones

• Chemicals excreted by humans and animals

• Elicits certain behaviour patterns

• Example: Androsterone causes changes in physiological functions, lille heart rate and mood states

• Example: Menstrual synchrony. Menstrual cycles of women who live together synchronize over time

• Also, when women are ovulating, guys can sort of sense that

• Taste

Gustation

• Sense of taste

• Four basic tastes: sweet, sour, salty, bitter

• Umami (fifth taste), response to glutamate found in protein rich foods like meat, milk, aged cheese, seafood

Flavour

• Combined sensory experience of taste, smell, touch

• Much of taste is from smell

• Brain perceives two distinctive flavours present in sweet and sour sauce quite separately

Taste Buds

• Small bumps called Papillae

• Four types of papillae

• Three types of papillae have taste buds

• Each taste bud has 60 to 100 receptor cells

• Lifespan of receptor cells: 10 days

• Taste buds continually replaced

• Non-Tasters: reduced ability to taste, smallest number of taste buds per square centimeter (96)

• Medium Tasters: nearly twice as many taste buds (184)

• Supertasters: more than four times as many taste buds (425)

• Current research is investigating potential links between taste sensitivity and health variables ie. obesity

Module 3.5

• The Mechanism of Touch

• Tactile information conveyed to brain when object touches skin

• Nerves endings send touch message through nerve connections to spinal cord

• Travels up spinal cord through brainstem, midbrain, to brain’s somatosensory cortex

• Pain: Physical Hurts

Gate Control Theory

• Pain signals can be transmitted or inhibited by “gate” in spinal cord

• Both cognitive and emotional factors can influence our perception of pain

• One recent study about pain found Indigenous People participants demonstrated greater anxiety around pain than participants of Euro decent

Endorphins

• Body produces our own natural pain killers

• Produce feelings of well-being

• Example: Runner’s high

Figure 3.11

• Two Point Threshold: measures how far apart two points must be to be felt as two separate touches

Module 3.6

• Other Senses

Kinesthetic Sense

• Feedback about movement and position of various body parts

Vestibular Sense

• Detects movement

• Provides information about body’s orientation in space

• Semicircular Canals

• Senses rotation of head when turning head side to side or spinning around

• Tube-like canals filled with fluid

• Rotating movements of head send fluid through canals

• Only signals changes in motion or orientation

Figure 3.12

(video - crash course homunculus)

Module 3.7

• Perception

• Sensory information actively organized

• Information interpreted by brain

• Sensations are raw material

• Perceptions are finished products

• Two basic principles: Gestalt and Perceptual Constancy

• Gestalt Principles of Perceptual Organization

Gestalt

• German word meaning whole form, pattern, configuration we perceive

• Two principles: figure and ground, grouping (similarity,proximity,continuity,closure)

Figure-Ground Principle

• Principle of perceptual organization

• Visual field perceived in terms of object (figure) against background (ground)

Figure 3.13

• Gestalt Principles of Grouping

Similarity

• Visual, auditory, other stimuli with similar characteristics

• Perceived as a unit

Proximity

• Objects close together in space or time perceived as belonging together

Continuity

• Perceive figures or objects as belonging together

• Appear as continuous pattern

Closure

• If parts of figure missing, perceive as whole

Figure 3.14

• Perceptual Constancy

• View people and objects from different angles, distances, lighting conditions

• See as maintaining same size, shape, brightness, colour

Size Constancy

• See same size regardless of changes in retinal image

Shape Constancy

• See stable or unchanging shape regardless of differences in viewing angle

Figure 3.15

Brightness Constancy

• See same brightness regardless of differences in lighting conditions

Colour Constancy

• See same colour under different conditions of illumination

• Binocular Depth Cues

• Cues from both eyes

• All about depth perception

• Seeing 3-D vision with the help of both of our eyes from further

Convergence

• Eyes turn inward while focusing nearby objects

• Closer object, greater convergence

Binocular Disparity (retinal disparity)

• Difference between two retinal images

• Cues for depth and balance

• Monocular Depth Cues

• Cues from one eye

• When we see art as 3D and it’s painted flat

Interposition

• Perceive partially blocked object as farther away

Linear Perspective

• Parallel lines appear to converge into distance

Relative Size

• Larger objects perceived as closer to viewer, smaller objects as farther away

Texture Gradient

• Nearby objects appear to have sharply defined textures

• Similar objects appear smoother

• Appear fuzzier as recede into distance

Atmospheric Perspective

• Also called aerial perspective

• Distant objects have bluish tint

• Distant objects appear more blurred than close objects

Shadow or Shading

• Distinguish bulges from indentations by their shadows

Motion Parallax

• Look out side window of moving vehicle

• Objects appear to be moving in opposite direction

• Objects seem to be moving at different speeds

• Close objects appear to move faster than distant ones

Figure 3.16

• Motion Perception

• Perception of motion and its relation to space it is in

• Real Motion = movements of objects through space

• Apparent Motion = psychological

• Phi Phenomenon (stroboscopic motion); neon lights flashing looks like movement

• Autokinetic Illusion: stare at single unmoving light in dark room, appears to move

(video - apparent motion)

Figure 3.17

• Extraordinary Perceptions

Ambiguous Figures

• Two different objects

• Figures seen alternately

Figure 3.18

Impossible Figures

• Parts appear to be two different places at same time

Figure 3.19

Illusions

• False perception of actual stimulus in environment

• Müller-Lyer Illusion and Ponzo Illusion

Cultural Differences in Visual Illusions

• One study found that members of the Navajo Nation who had lived in round houses (hogan) rather than typical North American houses, for the first six years of life, tended not to see he Müller-Lyer Illusion

Figure 3.20

Figure 3.21

Module 3.8

• Bottom-up Processing

• Why other perceptions are different than yours

• Individual components of stimulus detected by sensory receptors

• Information transmitted to areas of brain then combined, assembled into whole pattern person perceives

• Individual components sent to brain and combined to see the big picture

• Usually use this when we see new information

• Ex: trying to decipher your doctor’s writing on prescription

• Top-down Processing

• Past experience, knowledge of context plays role in forming perceptions

• We perceive more than sum of individual elements taken in by sensory receptors

• Ex: pharmacist can decipher your doctor’s prescription and fill it

• Influences on Perception

Perceptual Set

• Expectations affect perceptions because we have seen it in the past

Attention

• Process of sorting sensations and selecting some for further processing

• Inattentional blindness = failure to notice changes in objects if not directly paying attention