Module 1 Discovering Psychology. INTRODUCTION Growing up in a strange world –Autism especially abnormal or impaired development in social interactions,

Module 1

Discovering Psychology

INTRODUCTION• Growing up in a strange world

– Autism• especially abnormal or impaired development in

social interactions, such as hiding to avoid people, not making eye contact, and not wanting to be touched

– Autism is marked by difficulties in communicating, such as grave problems in developing spoken language or in initiating conversations

DEFINITION OF PSYCHOLOGY

• What do psychologists study?– Psychology

• the systematic, scientific study of behaviors and mental processes

– Behaviors • refers to observable actions or responses in both

humans and animals– Mental processes

• not directly observable, refer to a wide range of complex mental processes, such as thinking, imagining, studying, and dreaming

GOALS OF PSYCHOLOGY

– Describe– Explain– Predict– Control

GOALS OF PSYCHOLOGY (CONT.)

• Describe– first goal of psychology is to describe the different

ways that organisms behave• Explain

– second goal of psychology is to explain the cause of behavior

GOALS OF PSYCHOLOGY (CONT.)

• Predict– third goal of psychology is to predict how organisms

will behave in certain situations• Control

– the fourth goal of psychology is to control an organism’s behavior

ANSWERING QUESTIONS

• How do psychologists answer questions?– Approaches to understanding behavior include:

• Biological• Cognitive• Behavioral• Psychoanalytic• Humanistic• Cross cultural

ANSWERING QUESTIONS (CONT.)

• Biological approach– focuses on how our genes, hormones, and nervous

system interact with our environments to influence learning, personality, memory, motivation, emotions, and coping techniques

– Examples:• Autism• Autism runs in families; supported by the findings

in identical twins• If one twin has autism, there is a high 90% chance

the other twin will exhibit signs for autistic behavior


• Cognitive approach– examines how we process, store, and use information

and how this information influences what we attend to, perceive, learn, remember, believe, and feel

– Cognitive neuroscience:• Involves taking pictures and identifying the

structures and functions of the living brain during the performance of a wide variety of mental or cognitive processes, such as thinking, planning, naming, and recognizing objects


• Behavioral approach– studies how organisms learn new behaviors or modify

existing ones, depending on whether events in their environments reward or punish these behaviors

– some behaviorists, such as Albert Bandura, disagree with strict behaviorism

– formulated a theory that includes mental or cognitive processes in addition to observable behaviors

– Social Cognitive Approach:• behaviors are influenced not only by environmental

events and reinforcers but also by observation, imitation, and thought processes


• Psychoanalytic approach– Based on the belief that childhood experiences

greatly influence the development of later personality traits and psychological problems

– stresses the influence of unconscious fears, desires, and motivations on thoughts, behaviors, and the development of personality traits and psychological problems later in life


• Humanistic approach– emphasizes that each individual has great freedom in

directing his or her future, a large capacity for personal growth, a considerable amount of intrinsic worth, and enormous potential for self-fulfillment


• Cross-cultural approach– examines the influence of cultural and ethnic

similarities and differences on psychological and social functioning of a culture’s members

– Differences in how countries diagnose autism:– United States:

• symptoms described 60 years ago• first thought to be caused by environmental

factors, (cold parents)• 1960’s changed to searching for biological

problems• Diagnoses begins at 2-3 years of age

HISTORICAL APPROACHES

• How did psychology begin?– Structuralism: Elements of the Mind– Functionalism: Functions of the Mind– Gestalt Approach: Sensations versus Perceptions– Behaviorism: Observable Behaviors

Module 2

• Psychology & Science

ANSWERING QUESTIONS

• Research methods– Survey– Case study– Experiment


• Researchers use all three methods– survey– case study– experiment

• each method provides a different kind of information

SURVEYS

• Survey – way to obtain information by asking many individuals– answer a fixed set of questions about particular

subjects

SURVEYS (CONT.)

• Disadvantages– information can contain errors– results can be biased

• Advantage– efficient way to obtain much information from a large

number of people

CASE STUDY

• Case study – an in-depth analysis of the thoughts, feelings, beliefs,

experiences, behaviors, or problems of a single individual

– Personal Case Study: Testimonial• statement in support of a particular viewpoint based

on detailed observation of a person’s own personal experience

– Error and Bias: Self-fulfilling Prophecy• A strong belief or making a statement (prophecy)

about a future behavior and then acting, usually unknowingly, to fulfill or carry out the behavior

CASE STUDY (CONT.)

• Disadvantage– detailed information about a particular person may not

apply to others• Advantage

– detailed information allows greater understanding of a particular person’s life

EXPERIMENT

• Experiment – a method for identifying cause-and-effect

relationships by following a set of rules and guidelines that minimize the possibility of error, bias, and chance occurrences

EXPERIMENT (CONT.)

• Disadvantage– information obtained in one experimental situation or

laboratory setting may not apply to other situations• Advantage

– has the greatest potential for identifying cause-and-effect relationships with less error and bias than either surveys or case studies

CULTURAL DIVERSITY: USE OF PLACEBOS

• Placebo– intervention, such as taking a pill, receiving

and injection, or undergoing an operation, that resembles medical therapy but which in fact, has no medical effects

• Placebo effect– change in the patient’s illness that is

attributable to an imagined treatment rather than to a medical treatment

CULTURAL DIVERSITY: USE OF PLACEBOS (CONT.)

– researchers believe that placebos work by reducing tension and distress and by creating powerful self-fulfilling prophecies

– individuals think and behave as if the drug, actually a placebo, is effective

CULTURAL DIVERSITY: USE OF PLACEBOS (CONT.)

• Placebo examples– Rhino Horn– Bear Gallbladders– Tiger Bones– Cough Medication

CORRELATION

• Correlation– an association or relationship between the occurrence

of two or more events• Correlation coefficient

– a number that indicates the strength of a relationship between two or more events: the closer the number is to –1.00 or +1.00, the greater is the strength of the relationship

CORRELATION

CORRELATION (CONT.)

• Perfect positive correlation coefficient– +1.00 means that an increase in one event is always

matched by an equal increase in a second event• Positive correlation coefficient

– indicates that as one event tends to increase, the second event tends to, but does not always, increase

– increases from +0.01 to +0.99 indicate a strengthening of the relationship between the occurrence of two events

CORRELATION (CONT.)

• Zero correlation– indicates that there is no relationship between the

occurrence of one event and the occurrence of a second event

• Negative correlation coefficient– indicates that as one event tends to increase, the

second event tends to, but does not always, decrease– -0.01 to -0.99 indicates a strengthening in the

relationship of one event increasing and the other decreasing

CORRELATION (CONT.)

• Perfect negative correlation coefficient– -1.00 means that an increase in one event is always

matched by an equal decrease in a second event– correlations such as –1.00 are virtually never found in

applied psychological research

DECISIONS ABOUT DOING RESEARCH

• What is the best technique for answering a question?– Questionnaires and interviews– Laboratory experiments– Standardized tests– Animal models

DECISIONS ABOUT DOING RESEARCH (CONT.)

• Interview– technique for obtaining information by asking

questions, ranging from open-ended to highly structured, about a subject’s behaviors and attitudes, usually in a one-on-one situation

• Questionnaire– technique for obtaining information by asking subjects

to read a list of written questions and check off specific answers


• Laboratory experiments– techniques to gather information about the brain,

genes, or behavior with the least error and bias by using a controlled environment that allows careful observation and measurement

• Standardized tests– technique to obtain information by administering a

psychological test that has been given to hundreds of people and shown to reliably measure thought patterns, personality traits, emotions, or behaviors


• Animal Models– involves examining or manipulating some behavioral,

genetic, or physiological factor that closely approximates some human problem, disease, or condition

– Example:• human stem cell transplants in mice with spinal

cord injuries


• Choosing research settings– Naturalistic setting– Laboratory setting


• Naturalistic setting– relatively normal environment in which researchers

gather information by observing individuals’ behaviors without attempting to change or control the situation

• Laboratory setting– involves studying individuals under systematic and

controlled conditions, with many of the real-world influences eliminated

SCIENTIFIC METHOD: EXPERIMENT

• Advantages of scientific method– Scientific Method

• approach of gathering information and answering questions so that errors and biases are minimized

SCIENTIFIC METHOD: EXPERIMENT (CONT.)

• Conducting an Experiment: seven rules– Rule 1: Ask– Rule 2: Identify– Rule 3: Choose– Rule 4: Assign– Rule 5: Manipulate– Rule 6: Measure– Rule 7: Analyze


• Rule 1: Ask– hypothesis – educated guess about some phenomenon stated in

precise, concrete language to rule out any confusion or error in the meaning of its terms


• Rule 2: Identify– independent variable

• a treatment or something that the researcher controls or manipulates

– dependent variable• one or more of the subjects’ behaviors that are

used to measure the potential effects of the treatment or independent variable


• Rule 3: Choose– random selection

• each participant in a sample population has an equal chance of being selected for the experiment

• Rule 4: Assign– experimental group

• those who receive the treatment• control group• participants who undergo all the same procedures

as the experimental participants except that the control participants do not receive the treatment


• Rule 5: Manipulate– double blind procedure

• neither participants nor researchers know which group is receiving which treatment

• Rule 6: Measure– by manipulating the treatment so that the

experimental group receives a different treatment than the control group, researchers are able to measure how the independent variable (treatment) affects those behaviors that have been selected as the dependent variables


• Rule 7: Analyze– statistical procedures

• used to determine whether differences observed in dependent variables (behaviors) are due to independent variables (treatment) or to error or chance occurrence

Module 3

Brain’s Building Blocks

DEVELOPMENT OF THE BRAIN

• fact that your brain does not develop into a nose is because of instructions contained in your genes

• Genes– chains of chemicals that are arranged like rungs on a

twisting ladder

– there are about 20,000-25,000 genes that contain chemical instructions that equal about 300,000 pages of written instructions

– genes program the development of individual parts into a complex body & brain

DEVELOPMENT OF THE BRAIN (CONT.)

DEVELOPMENT OF THE BRAIN (CONT.)

• Insert pictures of – Six week old brain– Mature brain

STRUCTURE OF THE BRAIN

• Human brain:– is shaped like a small wrinkled melon– 1,350 grams (less than 3 pounds)– pinkish-white color– consistency of firm Jell-O– Fueled by sugar (glucose)– 1 trillion cells divided into

• glial cells• neurons

STRUCTURE OF THE BRAIN (CONT.)

• Glial cells

• 3 Functions:– guide the growth of developing neurons– wrap around neurons and form an insulation

to prevent interference from other electrical signals

– release chemicals that influence a neuron’s growth and function



• Neuron – a brain cell with 2 specialized extensions– one extension is for receiving electrical

signals– the other extension is for transmitting

electrical signals



• Insert: video Main Parts of the Neuron, Psychology Digital Video Library 3.0. Debra Schwiesow, page 17

GROWTH OF NEW NEURONS

• Can a brain grow new neurons?– canary brain

• can grow about 20,000 neurons a day during the spring (learns new breeding song)

– primate and human brain• researchers conclude that adult monkey and human

brains are capable of growing relatively limited numbers of neurons throughout adulthood

• Some new neurons play important role in continuing to learn and remember new things (hippocampus)

GROWTH OF NEW NEURONS (CONT.)

• Repairing the Brain– advances in stem research suggest the

human brain may be able to grow more neurons

– repair damages:• accident• disease• Alzheimer’s

PARTS OF THE NEURON

• Cell Body

– large egg-shaped structure that provides fuel, manufactures chemicals, and maintains the entire neuron in working order

• Dendrite

– branchlike extensions that arise from the cell body

– receive signals from other neurons, muscles, or sense organs

– pass these signals onto the cell body

PARTS OF THE NEURON (CONT.)

• Axon– a single threadlike structure that extends from

and carries signals away from the cell body to neighboring neurons, organs, or muscles

• Myelin Sheath– looks like separate tubelike segments

composed of fatty material that wraps around and insulates an axon

– prevents interference from electrical signals generated in adjacent axons

PARTS OF THE NEURON (CONT.)

• End bulbs or Terminal bulbs– located at extreme ends of the axon’s branches– miniature container that stores chemicals called

neurotransmitters (used to communicate with neighboring cells)

• Synapse– infinitely small space (20-30 billionths of a meter)– exists between and end bulb and its adjacent

body organ, heart, muscles, or cell body

ALZHEIMER’S DISEASE AND NEURONS

• Alzheimer’s disease– excessive buildup of gluelike substances– gradually destroy neurons

• Researchers recently discovered an experimental vaccine that may help stop the buildup of these gluelike, killer substances and they continue to search for other interventions

PERIPHERAL & CENTRAL NERVOUS SYSTEM

• Peripheral Nervous System– made up of nerves that are located

throughout the body, except in the brain & spinal cord

• Central Nervous System– made up of neurons located in the brain &

spinal cord

PERIPHERAL & CENTRAL NERVOUS SYSTEM (CONT.)

• Nerves– stringlike bundles of axons and dendrites that

come from the spinal cord and are held together by connective tissue

– carry information from the senses, skin, muscles, and the body’s organs to and from the spinal cord

– nerves in the peripheral nervous system have the ability to grow or reattach if severed or damaged

SENDING INFORMATION: ACTION POTENTIAL

SEQUENCE– axon membrane has chemical gates that can

open to allow electrically charged particles to enter or can close to keep out these particles

– ions are chemical particles that have electrical charges

– opposite charges attract and like charges repel

SENDING INFORMATION: ACTION POTENTIAL SEQUENCE (CONT.)


• Resting state– the axon has a charge– the charge results from the axon membrane

separating positive ions on the outside from negative ions on the inside


• Action potential– tiny electric current that is generated when the

positive sodium ions rush inside the axon– enormous increase of sodium ions inside the

axon causes the inside of the axon to reverse its charge

– inside becomes positive and outside becomes negative


The Action Potential

PLAYVIDEO

SENDING INFORMATION: NERVE IMPULSE

• Sending information– action potential is a tiny electrical current that

is generated when the positive sodium ions rush inside the axon

– the enormous increase of Na ions inside the axon causes the inside to reverse its charge

– the inside becomes positive & the outside becomes negative

SENDING INFORMATION: NERVE IMPULSE (CONT.)

• All-or-None law– if an action potential starts at the beginning of

the axon, the action potential will continue at the same speed segment to segment to the very end of the axon

• Nerve impulse– nerve impulse is made up of 6 action

potentials, with the first occurring at the beginning of the axon

SENDING INFORMATION: NERVE IMPULSE (CONT.)

TRANSMITTERS

• A transmitter is a chemical messenger that transmits information between nerves and body organs, such as muscles and heart

• Excitatory and Inhibitory– excitatory transmitters

• open chemical locks and turn on neurons

– inhibitory transmitters• block chemical locks and turn off neurons

NEUROTRANSMITTER

• Neurotransmitters– dozens of different chemicals that are made

by neurons and then used for communication between neurons during the performance of mental or physical activities

ALCOHOL

• Alcohol (ethyl alcohol)– A psychoactive drug that is classified as a

depressant, which means that it depresses the activity of the central nervous system

ALCOHOL

REFLEX

• Reflex– unlearned, involuntary reaction to some

stimulus– neural connections underlying a reflex are

prewired by genetic instructions

REFLEX (CONT.)

• Reflex sequence– sensors

• sensors trigger neurons that start the withdrawal effect

– afferent neurons• carry information from the senses to the spinal

cord

REFLEX (CONT.)

– Interneuron• relatively short neuron whose primary task

is making connections between other neurons

– Efferent neuron• carry information away from the spinal cord

to produce responses in various muscles and organs throughout the body

Module 4

Incredible Nervous System

GENES & EVOLUTION (CONT.)

• Fertilization– human life has its beginnings when a father’s sperm,

which contains 23 chromosomes, penetrates a mother’s egg, which contains 23 chromosomes



• Zygote– the largest human cell, about the size of a grain of

sand– a zygote is a cell that results when an egg is fertilized– a zygote contains 46 chromosomes arranged in 23

pairs


• Genes and proteins– Gene

• a specific segment on the long strand of DNA that contains instructions for making proteins

– Proteins• chemical building blocks from which all the parts of

the brain and body are constructed


• Genome– The Human Genome Project– began in 1995 and cost over $2.7 billion– reached its first goal in 2003 of mapping all the

human genes– researchers found only about 30,000 human genes

instead of the estimated 100,000

EVOLUTION OF THE HUMAN BRAIN

• Evolution of the human brain– 1859 Charles Darwin published the Origin of Species

• Theory of Evolution– says that different species arose from a common

ancestor and that those species that survived were best adapted to meet the demands of their environment

– humans and chimpanzees share at least 98% of their DNA

STUDYING THE LIVING BRAIN (CONT.)

• MRI– magnetic resonance imagery– involves passing nonharmful radio frequencies

through the brain• fMRI

– functional magnetic resonance imaging– measures the activity of specific neurons that are

functioning during cognitive tasks, such as thinking, listening


• Brain scans and Cognitive Neuroscience– PET scan– positron emission tomography– involves injecting a slightly radioactive solution into

the blood and then measuring the amount of radiation absorbed by brain cells called neurons


• Brain scans and Cognitive Neuroscience– Neuroimaging

• PET and fMRI scans are used to identify and map the living brain’s neural activity as a person performs complex behavioral and cognitive tasks, such as:

– seeing– moving– thinking– speaking– empathizing– trusting– even reacting to TV violence

ORGANIZATION OF THE BRAIN (CONT.)

• Central nervous system - CNS– made up of the brain and spinal cord


• Peripheral nervous system - PNS– includes all the nerves that extend from the spinal

cord and carry messages to and from various muscles, glands, and sense organs located throughout the body

• Subdivisions of the PNS– somatic nervous system– autonomic nervous system - ANS– sympathetic division– parasympathetic division


• Somatic nervous system– network of nerves that connect either to sensory

receptors or to muscles that you can move voluntarily, such as muscles in your limbs, back, neck, and chest

– nerves contain two kinds of fibers• Afferent

– sensory fibers; carry information to the brain• Efferent

– motor fibers; carry information from brain or spinal cord to the muscles


• Autonomic nervous system - ANS– regulates heart rate, breathing, blood pressure,

digestion, hormone secretion, and other functions• Sympathetic division

– triggered by threatening or challenging physical or psychological stimuli, increases physiological arousal and prepares the body for action

• Parasympathetic division– returns the body to a calmer, relaxed state and is

involved in digestion


• Major Parts of the Brain– Forebrain– Midbrain– Hindbrain

• pons• medulla• cerebellum


• Forebrain– largest part of the brain– has right and left sides called hemispheres– hemispheres are responsible for a number of

functions, including learning and memory, speaking and language, emotional responses, experiencing sensations, initiating voluntary movements, planning, and making decisions


• Midbrain– has a reward or pleasure center, which stimulated by

food, sex, money, music, looking at attractive faces, and some drugs (cocaine)

– has areas for visual and auditory reflexes– contains the reticular formation, which arouses the

forebrain so that it is ready to process information from the senses


• Hindbrain– Has three distinct structures:

• Pons• Medulla• Cerebellum


• Pons– functions as a bridge to interconnect messages

between the spinal cord and brain• Medulla

– located on top of the spinal cord– includes a group of cells that control vital reflexes,

such as respiration, heart rate, and blood pressure• Cerebellum

– located in the very back and underneath the brain– involved in coordinating motor movements but not in

initiating voluntary movements

CONTROL CENTERS: FOUR LOBES (CONT.)

• Frontal lobe– involved with personality, emotions, and motor

behaviors• Parietal lobe

– involved with perception and sensory experiences• Occipital lobe

– involved with visual processing• Temporal lobe

– involved with hearing and speaking


• Temporal lobe: functions– primary auditory cortex– located on top edge of each temporal lobe, receives

electrical signals from receptors in the ears and transforms these signals into meaningful sound sensations, such as vowels and consonants


• Temporal lobe: functions– auditory association area– located directly below the primary auditory cortex– transforms basic sensory information, such as noises

or sounds, into recognizable auditory information, such as words or music


• Occipital lobe: functions– vision– primary visual cortex– located at the very back of the occipital lobe– receives electrical signals from receptors in the eyes

and transforms these signals into meaningless basic visual sensations, such as lights, lines, shadows, colors, and textures


• Occipital lobe: functions– visual association area– transforms basic sensations, such as lights, lines,

colors, and textures, into complete, meaningful visual perceptions, such as persons, objects, or animals


• Visual agnosia– individual fails to recognize some object, person, or

color– has ability to see and even describe pieces or parts of

some visual stimulus


• Neglect Syndrome– refers to the failure of a patient to see objects or parts

of the body on the side opposite the brain damage– may dress only on one side of body– may deny that opposite body parts are theirs

LIMBIC SYSTEM: OLD BRAIN

• group of about half a dozen interconnected structures that make up the core of the forebrain

• involved with regulating many motivational behaviors such as obtaining food, drink, and sex

• organizing emotional behaviors such as fear, anger, and aggression; storing memories

• Structures and functions– Hypothalamus– Amygdala– Thalamus– Hippocampus

LIMBIC SYSTEM: OLD BRAIN

• Structures and functions– Hypothalamus– Amygdala– Thalamus– Hippocampus

LIMBIC SYSTEM: OLD BRAIN (CONT.)

• Autonomic nervous system– Sympathetic– Parasympathetic


• Autonomic nervous system– Sympathetic

• triggered by threatening or challenging physical or psychological stimuli

– Physiological responses• increased heart rate, increased blood pressure,

and dilated pupils• fight or flight


• Autonomic nervous system– Parasympathetic

• decreases physiological arousal• returns the body to a calmer, more relaxed state• stimulates digestion during eating

– Physiological responses• decreases heart rate• lowers blood pressure• stimulate digestion• body returns to more relaxed state


• Autonomic nervous system– Homeostasis

• sympathetic and parasympathetic systems work together to keep the body’s level of arousal in balance for optimum functioning

Module 5

Sensation

THREE DEFINITONS

• Adaptation:– the decreasing response of the sense organs, the

more they are exposed to a continuous level of stimulation

• Sensation versus perception:– relatively meaningless bits of information that result

when the brain processes electrical signals that come from the sense organs

– perceptions:– meaningful sensory experiences that result after the

brain combines hundreds of sensations

THREE DEFINITONS (CONT.)

• eyes, ears, nose, skin, and tongue are complex, miniaturized, living sense organs that automatically gather information about your environment

• Transduction:– process in which a sense organ changes, or

transforms, physical energy into electrical signals that become neural impulses, which may be sent to the brain for processing

EYE: VISION

• Structure and function– eyes perform two separate processes– first: gather and focus light into precise area in

the back of eye– second: area absorbs and transforms light

waves into electrical impulses– process called transduction

EYE: VISION (CONT.)

• Structure and function– Vision: 7 steps

• Image reversed• Light waves• Cornea• Pupil• Iris• Lens• Retina

EYE: VISION (CONT.)

• rods:– photoreceptor that contain a single chemical,

called rhodopsin– activated by small amounts of light– very light sensitive– allow us to see in dim light– see only black, white and shades of gray

EYE: VISION (CONT.)

• cones:– photoreceptors that contain three chemicals

called opsins– activated in bright light– allow us to see color– cones are wired individually to neighboring

cells– allows us to see fine detail

EYE: VISION (CONT.)

• Visual pathways: eye to brain– Primary visual cortex

• the back of the occipital lobes is where primary visual cortex transforms nerve impulses into simple visual sensations

– Visual association areas• the primary visual cortex sends simple visual

sensations to neighboring association areas

EYE: VISION (CONT.)• Color Blindness

– inability to distinguished two or more shades in the color spectrum

– Monochromatic:• total color blindness

• black and white

• result of only rods and one kind of functioning cone

– Dichromatic:• trouble distinguishing red from green

• two kinds of cones

• inherited genetic defect

• mostly in males

• See mostly shades of green

EAR: AUDITION• Stimulus:

– Sound waves• stimuli for hearing (audition)• ripples of different sizes• sound waves travel through space with varying

heights and frequency

– Height • distance from the bottom to the top of a sound wave• called amplitude

– Frequency • number of sound waves occurring within one second

EAR: AUDITION (CONT.)

• Loudness– subjective experience of a sound’s intensity– brain calculates loudness from specific physical

energy (amplitude of sound waves)

• Pitch– subjective experience of a sound being high or low– brain calculates from specific physical stimuli– speed or frequency of sound waves– measured in cycles (how many sound waves in one

second)


• Outer, middle, and inner ear– Outer ear

• consists of three structures• external ear• auditory canal• tympanic membrane



• external ear– oval shaped structure that protrudes from the side of the

head

• function– pick up sound waves and then send them down the

auditory canal



• auditory canal– long tube that funnels sound waves down its length so

that the waves strike the tympanic membrane (ear drum)



• tympanic membrane– taut, thin structure commonly called the eardrum– Sound waves strike the tympanic membrane and cause

it to vibrate



• Outer, middle, and inner ear– Middle ear

• bony cavity sealed at each end by membranes. • the membranes are connected by three tiny bones

called ossicles• hammer, anvil and stirrup

– hammer is attached to the back of the tympanic membrane

– anvil receives vibrations from the hammer– stirrup makes the connection to the oval window (end

membrane)


• Outer, middle, and inner ear– Inner ear

• contains two structures sealed by bone– cochlea: involved in hearing– vestibular system: involved in balance


• Cochlea– bony coiled exterior that resembles a snail’s

shell– contains receptors for hearing– function is transduction– transforms vibrations into nerve impulses that

are sent to the brain for processing into auditory information

EAR: AUDITION (CONT.)• Auditory brain areas

– sensations and perceptions– two step process occurs after the nerve impulses

reach the brain– primary auditory cortex– top edge of temporal lobe– transforms nerve impulses into basic auditory

sensations– auditory association area – combines meaningless auditory sensations into

perceptions, which are meaningful melodies, songs, words, or sentences

VESTIBULAR SYSTEM: BALANCE

• Position and balance– vestibular system is located above the cochlea in the

inner ear– includes semicircular canals– bony arches set at different angles– each semicircular canal is filled with fluid that moves

in response to movements of your head– canals have hair cells that respond to the fluid

movement– function of vestibular system– include sensing the position of the head, keeping the

head upright, and maintaining balance

CHEMICAL SENSES• Taste

– chemical sense because the stimuli are various chemicals

– tongue– surface of the tongue– taste buds

CHEMICAL SENSES (CONT.)• Tongue

– Five basic tastes• sweet• salty• sour• bitter• umami: meaty-cheesy taste

CHEMICAL SENSES (CONT.)• Surface of the tongue

– chemicals, which are the stimuli for taste, break down into molecules

– molecules mix with saliva and run into narrow trenches on the surface of the tongue

– molecules then stimulate the taste buds

CHEMICAL SENSES (CONT.)• Taste buds

– shaped like miniature onions– receptors for taste– chemicals dissolved in saliva activate taste buds– produce nerve impulses that reach areas of the

brain’s parietal lobe– brain transforms impulses into sensations of

taste

• Flavor– combination of taste and smell

CHEMICAL SENSES (CONT.)

CHEMICAL SENSES (CONT.)• Smell, or olfaction

– Steps for olfaction• Stimulus• Olfactory cells• Sensation and memories• Functions of olfaction

CHEMICAL SENSES (CONT.)• Smell, or olfaction

– Olfactory cells• receptors for smell are located in a I-inch-square

patch of tissue in the uppermost part of the nasal passages.

• olfactory cells are covered in mucus• which dissolve volatile molecules and stimulate the

cells• the cells trigger nerve impulses that travel to the

brain• which interprets the impulses as different smells

CHEMICAL SENSES (CONT.)

• Smell, or olfaction– Sensations and memories

• nerve impulses travel to the olfactory bulb• impulses are relayed to the primary olfactory cortex• cortex transforms nerve impulses into olfactory

sensations• can identify as many as 10,000 different odors• we stop smelling our deodorants or perfumes

because of decreased responding• called adaptation

TOUCH• Touch

– includes pressure, temperature, and pain

TOUCH (CONT.)

TOUCH (CONT.)• Receptors in the skin

– skin– hair receptors– free nerve endings– Pacinian corpuscle

TOUCH (CONT.)• Skin

– outermost layer– thin film of dead cells containing no receptors– just below, are first receptors which look like

groups of threadlike extensions– middle and fatty layer– variety of receptors with different shapes and

functions– some are hair receptors

TOUCH (CONT.)• Hair receptors

– free nerve endings wrapped around the base of each hair follicle

– hair follicles fire with a burst of activity when first bent

– if hair remains bent for a period of time, the receptors will cease firing

– sensory adaptation– example: wearing a watch

TOUCH (CONT.)• Brain areas

– somatosensory cortex– located in the parietal lobe– transforms nerve impulses into sensations of

touch temperature, and pain

Module 6

Perception

PERCEPTUAL THRESHOLDS

• Threshold– a point above which a stimulus is perceived

and below which it is not perceived– threshold determines when we first become

aware of a stimulus

PERCEPTUAL THRESHOLDS (CONT.)

• Becoming aware of a stimulus– Gustav Fechner

• defined the absolute threshold as the smallest amount of stimulus energy (such as sound or light) that can be observed or experienced

– Absolute threshold• the intensity level of a stimulus such that a person

will have a 50% chance of detecting it


• Subliminal stimulus– has an intensity that gives a person less than

a 50% chance of detecting the stimulus

– breast cancer• accuracy problems

– looking for ways to lower the threshold for detecting cancerous tumors and thus save patients

– recently, use of digital mammograms (allows for images to be enhanced or magnified) is better in detecting cancerous tumors in women


• E. H. Weber– worked on the problem of how we judge whether a

stimulus, such as loud music, has increased or decreased in intensity

– concept of just noticeable difference (JND)– refers to the smallest increase or decrease in the

intensity of a stimulus that a person is able to detect

• Weber’s law– The increase in intensity of a stimulus needed to

produce a just noticeable difference grows in proportion to the intensity of the initial stimulus.

SENSATION VERSUS PERCEPTION

• Basic Differences– Sensations

• our first awareness of some outside stimulus• outside stimulus activates sensory receptors, which

in turn produce electrical signals that are transformed by the brain into meaningless bits of information

– Perceptions• the experience we have after our brain assembles

and combines thousands of individual sensations into a meaningful pattern or image

SENSATION VERSUS PERCEPTION (CONT.)

• Changing sensation into perception– Stimulus

• change of energy in the environment, such as light waves, sound waves, mechanical pressure, or chemicals

– Transduction• change physical energy into electrical signals• electrical signals are changed into impulses that travel

into the brain

– Brain• impulses from senses first go to different primary areas

of the brain

SENSATION VERSUS PERCEPTION (CONT.)

• Changing sensation into perception– brain: association areas– sensation impulses are sent to the

appropriate association area in the brain

• Personalized perceptions– each of us has a unique set of personal

experiences, emotions, and memories that are automatically added to our perceptions by other areas of the brain

RULES OF ORGANIZATION

• Structuralist versus Gestalt psychologists– Structuralists

• believed that you add together hundreds of basic elements to form complex perceptions

– Gestaltists• believe our brains follow a set of rules that specify

how individual elements are to be organized into a meaningful pattern, or perception

RULES OF ORGANIZATION (CONT.)

• Organizational rules– rules of organization: identified by Gestalt

psychologists• specify how our brains combine and organize individual

pieces or elements into a meaningful perception

– Figure-ground• states: in organizing stimuli, we tend to automatically

distinguish between a figure and a ground

– Similarity• states: in organizing stimuli, we group together elements

that appear similar

RULES OF ORGANIZATION (CONT.)

– Closure• states: in organizing stimuli, we tend to fill in any missing

parts of a figure and see the figure as complete

– Proximity• states: in organizing stimuli, we group together objects

that are physically close to one another

– Simplicity• states: stimuli are organized in the simplest way possible

– Continuity• states: in organizing stimuli, we tend to favor the smooth

or continuous paths when interpreting a series of points or lines

PERCEPTUAL CONSTANCY

• Size, shape, brightness & color constancy– Size constancy

• refers to our tendency to perceive objects as remaining the same size even when their images on the retina are continually growing or shrinking

– Shape constancy• refers to our tendency to perceive an object as

retaining its same shape even though when we view it from different angles, its shape is continually changing its image on the retina

PERCEPTUAL CONSTANCY (CONT.)

• Size, shape, brightness & color constancy– Brightness constancy

• refers to the tendency to perceive brightness as remaining the same in changing illumination

– Color constancy• refers to the tendency to perceive colors as

remaining stable despite differences in lighting

DEPTH PERCEPTION

• Binocular (two eyes) depth cues– Depth perception

• refers to the ability of your eye and brain to add a third dimension, depth, to all visual perceptions, even though images projected on the retina are in only two dimensions, height, and width

– Binocular depth cues• depends on the movement of both eyes

– Convergence• refers to a binocular cue for depth perception based on

signals sent from muscles that turn the eyes

DEPTH PERCEPTION

DEPTH PERCEPTION (CONT.)


• Monocular depth cues– produced by signals from a single eye– Linear perspective

• monocular depth cue that results as parallel lines come together, converge, in the distance

– Relative size• monocular depth cue that results when we expect two

objects to be the same size and they are not

– Interposition• monocular depth cue that comes into play when objects

overlap


• Monocular depth cues– Light and shadow

• monocular depth cues where brightly lit objects appear closer, while objects in shadows appear farther away

– Texture gradient• monocular depth cue in which areas with sharp,

detailed texture are interpreted as being closer and those with less sharpness and poorer detail are perceived as more distant


• Monocular depth cues– Atmospheric perspective

• monocular depth cue that is created by the presence of dust, smog, clouds, or water vapor

– Motion parallax• monocular depth cue based on the speed of

moving objects

ILLUSIONS

• Strange perceptions– Illusion

• a perceptual experience in which you perceive an image as being so strangely distorted that, in reality, it cannot and does not exist

– Impossible figure• perceptual experience in which a drawing seems

to defy basic geometric laws

ILLUSIONS (CONT.)

SUBLIMINAL PERCEPTION

• Subliminal Message– brief auditory or visual message that is

presented below the absolute threshold– means that there is less than a 50% chance

that the message will be perceived

• Self-fulfilling prophecies– involve having strong beliefs about changing

some behavior and then acting, unknowingly, to change that behavior

Documents

Module 1 Discovering Psychology. INTRODUCTION Growing up in a strange world –Autism especially abnormal or impaired development in social interactions,