•
•
•
•
Each of the three cone types responds to 2 different wavelengths
Red or green
Blue or yellow
Black or white
Dual-process theory• Combines the trichromatic and opponent-process theories
• Retina: Red, green and blue color cones
• Nervous system: signals are processed by opponent-process cells
Hearing• Sound waves
• Amplitude-determines loudness
• Wavelength- determines pitch
• Frequency rage- humans –20 to 20000 Hz
• Loudness- humans –absolute threshold: 0 decibels
How do we translate sound energy into neural messages?
• Sound waves pass through the auditory canal to the ear drum
• Ear drum vibrates and this vibration is transmitted to the cochlea (through the hammer,
anvil and stirrup)
• The vibrations cause the oval window (cochlea’s membrane) to vibrate jostling the fluid
that fills the tube
• This motion causes ripples in the basilar membrane, which is lined with hair cells
• The movement of these hair cells triggers impulses in the adjacent nerve fibers
Touch• Normally thought of as the detection of pressure against the skin
• Sense of touch is a mix of at least 4 distinct skin senses:
-Pressure
-Warmth
-Cold
-Pain
• Thermoreceptors- sense temperature changes at or near our skin
• Provide input to keep our body’s temperature regulation at 98.6 degrees F
• Warm and cold thermoreceptors
• Pain – is the sensation that warns us that damage to our bodies is occurring
• There is not a specific type of stimulus that triggers pain
• Nociceptors: sensory receptors that detect hurtful temperatures, pressure or chemicals
Smell•
Smell can provide us with important information:
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Correlational Studies- Correlations: exists whenever 2 variables are associate or related to
each other in some fashion
-Positive correlation (AKA direct correlation): two things increase or decrease together
-Negative correlation: indicate an inverse relationship- as one thing increases, the other
decreases
-Correlation coefficient: indicates the strength and direction of correlation
-Important: Correlation does not imply causation.
✓ Pearson’s r ranges from -1.00 to +1.00
✓ R= 0.00 no relationship between variables
✓ R= +1.00 perfect positive correlation
✓ R= -1.00 perfect negative correlation
-Directionality problem
-Third variable problem
Experimentation- Investigates cause and effect relationships
-Important: Investigator manipulates the factors of interest, while holding constant other
factors
-Independent variable: The variable that is being manipulated
-Dependent variable: What is being measured
-Control condition: Serves as a comparison for the experimental condition
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The Neuron• Nerve cell
• 3 main parts:
a) Dendrites- Branching extensions that receive chemical messages and conduct them to
the cell body.
b) Cell Body- Contains the neuron’s nucleus (with DNA and typical nuclear organelles).
c) Axon- Take information away from the body cell to other neurons or to muscles or
glands.
-Action potential (“impulse”): occurs when chemicals contact the surface of the neuron
(changing the balance of ions) and a brief electrical charge travels down the axon
-Myelin Sheath: fatty tissue that covers the axon of some neuron and helps speed neural impulses
-Threshold- There is a certain level of stimulation that is required to trigger an action potential
-All or none principle: if the threshold is not reached, then no action potential will fire; if the
threshold is reached, an action potential (always the same size) will fire
NeurotransmittersSynapse: the junction between the axon tip of the sending neuron and the dendrite of the
receiving neuron. The tiny gap at this junction is called the synaptic gap.
-Neurotransmitters: Chemical messengers that traverse the synaptic gaps between neurons
Examples- Dopamine- influences movement, learning, attention and emotion
Serotonin- affects mood, hunger, sleep and arousal
Acetylcholine (Ach)- Enables action, learning and memory
Endorphins- “brain’s” natural painkiller: in response to pain, stress, and other vigorous exercise
-Reuptake: the process by which the sending neuron reabsorbs the excess neurotransmitters
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The Nervous System
Peripheral Nervous System (PNS)• Links the central nervous system with the body’s sense receptors, muscles and glands.
1. Somatic- Specializes in the control of voluntary movements and the communications of
information to and from the sense organs
2. Autonomic- Controls the parts of the body that function involuntarily without our
awareness
✓ Sympathetic- prepares body for defensive action
✓ Parasympathetic- Acts to calm the body after the emergency situation has been solved
Central Nervous System (CNS)
• Brain and spinal cord
1. Spinal Cord- Connects the peripheral nervous system to brain
2. Brain• Central Core- (The “old brain”)
a) Medulla- Unconscious functions (e.g., breathing, circulation)
b) Pons- Coordinates muscles integrates movements between the right and left
halves of the body. Involved in sleep and arousal
• Medulla + Pons = Brainstem
c) Cerebellum- Body balance. Involved in intellectual functions
d) Reticular Formation- Functions related to sleep, arousal, and attention
e) Thalamus- Messages from the senses are directed to higher brain regions
•
Limbic Systema) Hippocampus- Involved in the storage of memories
b) Amygdala- Involved in aggression and fear
c) Hypothalamus- Maintain homeostasis. Regulates basic biological needs (e.g.
hunger, thirst)
•
Cerebral Cortex- Where the highest mental functions, such as thinking and planning,
take place!!!!
a) Left Hemisphere- Receives information only from the RIGHT side of the
body
Concentrates more on tasks that require verbal competence (speaking, reading,
thinking, and reasoning)
•
•
b) Right Hemisphere- Receives information only from LEFT side of the body
Concentrates more in nonverbal tasks such as the understanding of spatial
relationships, recognition of patterns and drawings, music, ad emotional expression
Lateralization: The dominance of one hemisphere in specific functions
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The Cerebral cortex• How do we know about hemisphere specialization?
• Roger Sperry (1968) purposely legion area to stop seizures
• Corpus Callosum: Wide band of axon fibers that connects the 2 hemispheres
• Split brain research
• Left concentrates more on tasks that require verbal competence (speaking, reading,
thinking and reasoning) sees ball on right says ball
• Right concentrates more on nonverbal tasks such as the understanding of spatial
relationships, recognition of patterns and drawings, music and emotional expression
sees hammer from left so is able to draw but not say what it is
*Each hemisphere is subdivided into 4 regions:
• Frontal lobe
• Parental lobe
• Occipital lobe
• Temporal lobe
Functions of the Cerebral Cortex1. Motor Functions• Fritsch and Hitzig (1870) Experiments w/ dogs
• Wilder Penfield (1930s) Surgeries to stop cerebral palsy, mapped the motor cortex
using wide-awake patients
2. Sensory Functions• Wilder Penfield (1930s) mapped the sensory cortex
3. Higher mental functions (e.g. learning, remembering, thinking, and speaking)• Association areas
4. Language• Broca’s area- controls language and expression
• Wermicke’s area- controls language reception
Aphasia: inability to sue or understand written or spoken language
• Broca’s Aphasia difficulties in controlling the actual production of words
• Wernicke’s Aphasia difficulties in understanding the meaning of words
Frontal Lobe-
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• Control of voluntary movement
• Speaking
• Personality
• Making plans and judgement
-Lesions to the Frontal Lobe example Phineas Gage, survived metal bar to end, as he got better
his personality started to change, went from easy going, too hard to handle (1948)
Parietal Lobe• Receives sensory input for touch and body position
• Attention
• Spatial location
Occipital Lobe• Receives visual information from the visual fields
Temporal Lobe• Hearing
• Language processing
• memory
Sensation & PerceptionHow do we contrast our representations of the external world?
1. Detect physical energy from environment
2. Physical energy is encoded as neural signals
3. Information is selected, organized and interpreted
Sensation: allows the nervous system to receive and represent stimulus energy from our
environment
Perception: organizes and interprets sensory information
Which information do we extract from the environment?
We detect from the environment the information that we need to function and survive
We detect what are, for us, the important features of the environment
Psychophysics- area of psychology that studies the relationships between the physical
characteristics of stimuli, such as their intensity, and our psychological experience of them.
Threshold1. Absolute ThresholdThe lowest intensity at which a stimulus can be detected 50% of the time
Subliminal Stimulus: stimulus that is so weak or brief that although it is received
by senses, it cannot be perceived consciously
2. Difference Threshold (aka just noticeable difference)-
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The smaller difference between two stimuli that people can perceive 50%
of the time
The difference threshold increases with the magnitude of the stimulus
Weber’s law- to be perceived as different, two stimuli must differ by a
constant minimum percentage rather than a constant amount
Example: Lights: 8 % difference in intensity, Weight: 2% difference,
Tones: 0.3% difference in frequency
Sensory Adaption• Diminished sensitivity to an unchanging stimulus
• Adaption occurs in all sensory modalities
• Adaption allows our senses to pick up informative changes in the environment that could
be important to our well-being or survival
How do we “see” the world?
1. Light enters the eyes through the cornea (front of eye)
2. Light passes through the pupil (opening/ gap) amount of light that passes is regulated by
the iris
3. Lens helps focuses the incoming rays into an image on the retina
4. Light energy is converted into neural impulses and sent to the brain,
rods: retinal receptors that detect black, white and gray (on side) (120 million in eye)
(high sensitivity to dim light) (not color sensitive)
cones: receptor cells that detect fine, fine detail ad give rise to color sensations, (center),
(6 million in eye) (low sensitivity to light) (color sensitive), pigeons and chipmunks have
only cones in their retina- so they have color vision but very poor night vision!!!!
Optic nerve: carries the information to the brain
How do we “see” the colors?
Light Wavesamplitude: determines brightness
Wavelength: determines hue
Example: yellow flower to human, bee sees dark blue in the middle light blue on outside
so they can see where pollen is
Theories• Young- Helmholtz trichromatic theory
• Hering’s opponent-process theory
• Dual-process theory
Young-Helmholtz trichromatic theory• Individual cones are most sensitive to wavelengths that correspond to either blue, green,
or red
• What about yellow?
-red+green-pure color?
-red-green color-blind people
Hering’s opponent-process theory-
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-Food choices
-Tracking
-Recognition
-Senses and emotions from the past
How do we smell things?
• Chemical molecules reach receptors at the top of the nose and then these receptors and
messages to the brain
• How good are humans at recognizing smells?
-Human olfactory system can be improved
• Smell fingerprint?
• Hard to recall odors by name
Taste• Like smell it is a chemical sense
• Taste sensations:
-sweet
-sour
-salty
-bitter
-umami?
-elicited by glutamate
• Not only taste buds are involved in taste
• Sensory interaction: one sense may influence another, as when the smell of food
influences its taste
Perception• Is active, creative process in which raw sensory data are organized and given meaning
• How do we organize and interpret our sensations so they become meaningful
perceptions?
Gestalt Principles of perception Organization• We have tendency to integrate pieces of information into meaningful wholes
• The wholes we perceive are often more than the sum of their parts
• Figure-ground relations: Focal stimulus is perceived as a figure against a background of
other stimulus
Gestalt Laws of perceptual organization:
• Law of Similarity- we tend to group together figures that are similar to each other
• Law of Proximity- Elements that are near each other are likely to be perceived as part
of the same configuration
• Law of Closure- We tend to fill gaps to create a complete, whole object
• Law of Continuity- We tend to link individual elements together so they form a
continuous line or pattern that makes sense
Depth perceptions-
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We seem to have an innate ability to perceive depth
Binocular cues: cues that depend on the use of 2 eyes
1. Retinal disparity: each eye sees a slightly different image,
-the greater the disparity (difference) the closer the object
2. Convergence: the extent to which the eyes converge in ward
-the greater the inward strain, the closer the object
Monocular cues:
1. Relative size: if 2 objects ae assumed to be similar size, we perceive the one that
cast the smaller retinal image as farther away
2. Interposition: if one object partially blocks our view of another, we perceive it as
closer
3. Relative height: we perceive objects higher in our field of vision as father away
4. Linear perspective: since parallel lines appear to converge with distance, the more
the lines converge, the grater their perceived distance
5. Relative motion: the farther away the object, the lower its apparent speed
6. Light and shadow: since nearby objects reflect more light to our eyes, given to
identical objects, smaller one seems farther away
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• developed Functionalism
Sigmund Freud
• working with clients with "neuroses", developed theory of personality
• Psychodynamic perspective
• personality driven by unconscious forces beyond our control
Behaviorism
-John Watson, Ivan Pavlov, B. F. Skinner
-must study observable and measurable behavior
-argued that psychology is the study of behavior
1960s brought on the Cognitive Revolution
-how people think, understand, and know about their world
Current Perspectives:
1.
2.
3.
4.
5.
6.
biological (neuroscience and evolutionary)
behavioral
psychodynamic
cognitive
humanistic
sociocultural
Research Methods in Psychology
Scientific Method:
◦ Define the problem (identify questions of interest)
◦ Form hypothesis (formulate explanation)
◦ Design study and test hypothesis
◦ Analyze, interpret finds, draw conclusions
◦ Report findings
Important Goals of Research
1. measurement and description
2. explanation and understanding
3. prediction and control
Theories
• General principles that attempt to explain how several facts or events are related
◦ Organize facts; explains why things happen and predicts future events
◦ guides research
Notice an event
-people seem to get more active and aggressive after they witness a violent event
Develop or utilize a theory
-Theory: Exposure to violence leads to increased aggressiveness
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Psychology: the scientific study of behavior and mental processes
What is PSY 100?
-lot of work and high expectations
-UK core: inquiry into the social sciences
-general goals:
a) learn about psychology
b) understand psychological outlook
c) personal development
d) have fun
-most of us will overestimate what we think we know
-therapy decreases the amount of time it takes to get better from a disorder
-overtime your disorder will eventually get better
-you can disprove a theory but never prove a theory, you can only support it
Where does psychology fit into every day hobbies?
-sensation and perception
-learning and memory
-personality
-social psychology
-physiological psychology
-states of consciousness
-stress and health consequences
Types of psychologists:
-counseling
-clinical
-developmental
-personality
-industrial/ organizational
-physiological/ neuroscience
-educational
-cognitive: thought processes// perception
History:
Wilhelm Wundt
• opened the first experimental psychology lab in Leipzig, Germany in 1879
• studied the "content" of consciousness
• technique of introspection
looking inward to understand our thoughts
Edward Titchener
• student of Wundt's
• brought ideas to US and the methodology and discipline was termed Structuralism
William James
• disagreed with Wundt on important focus
• interested in how individuals function in real world
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Hypothesis
-specific statement that attempts to describe or explain behavior; describes relationship between variables
-leads to predictions about what will happen in a particular situation
-will incorporate two or more variables
-Variables: any measurable condition, event or characteristic that is controlled or observed in a study
What are the variables in our hypothesis?
-Hypothesis: children who watch more violent TV will engage in more aggressive behavior than those who
don't watch as much violent TV
Operational definition: statement of the procedures used to define research variables
◦ specific
◦ measurable
◦ defines the type of measurement used
Types of Measures
How are we going to measure the variables we're interested in?
1) Self report
-surveys/questionaries
-interviews
2) Behavioral
-naturalistic observation
-laboratory observation
3) Physiological measures
Measurement
Is thrill-seeking (personality variable) related to drug use in high school students?
How could I measure thrill-seeking?
How could I measure drug use?
Types of Research
1.
2.
3.
Descriptive research: research that provides an accurate portrayal of characteristics of a particular indiv,
situation, or group. These studies are a means of discovering new meaning, describing what exists,
determining the frequency with which something occurs, and categorizing information.
A. case studies
B. observation
C. survey research
Correlational research: the systematic investigation of relationships among two or more variables,
without necessarily determining cause and effect.
A. the association between variables
Experimental research: objective, systematic, controlled investigation for the purpose of predicting and
controlling phenomena and examining probability and causality among selected variables.
A. does one variable directly impact another variable
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Experiment
Do changes in X cause changes in Y?
1. Manipulation of independent variable(s)
2. Accurately measure dependent variable(s)
3. Control of extraneous variables
Independent variable (IV) : condition or event that experimenter varies in order to see its impact on another variable
(what changes / the experimenter can manipulate)
Dependent variable (DV) : variable that is thought to be affected by the manipulation of the independent variable
Basic Experiment:
2 Groups: Experimental group and control
• Is AZT effective in treating HIV
◦ Independent variable: AZT (the drug)
◦ Dependent variable: HIV
• Does alcohol increase feelings of happiness?
◦ Independent variable: alcohol
◦ Dependent variable: the person's happiness
• Does watching TV violence cause child aggressiveness?
◦ Independent variable: TV violence
◦ Dependent variable: level of aggression
• How would we set this up?
◦ name the amount of times the children get violent (push, shove, etc.) while watching the violent TV
show
◦ get an average of aggressive actions
Extraneous variables : any variables, other than the independent variable(s), that seem likely to influence the
dependent variable
-many of these variables controlled through random assignment
-want to make everything between conditions the same except for IV
Correlational designs
-is there an association between 2 variables?
-no manipulation of IV
-cannot demonstrate cause-effect
1. measure variables accurately
2. estimate their interrelations
3. maintain control over extraneous variables
Correlation: measure of the relationship between 2 variables
Correlation coefficient represented by "r"
-strength
-direction
-range
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Must be cautious in interpretation; CANNOT make casual inferences, regardless of the strength of the relationship
Why?
Correlation/Causation Problems
1. Directionality problem
2. Third variable problem
Evaluating Research
-Internal Validity: the results must accurately describe the true relationship under study
Problems:
a) social desirability bias
b) experimenter bias
c) sampling bias
-External validity: will the conclusions generalize to other people, places, and situations?
Communication within Body
1. nervous system
2. endocrine system
Nervous system
Comprised of cells
-neurons=nerve cells
-glia=provide structural support, etc.
Types of neurons:
1. motor neurons: transmit information from brain (or spinal cord) to muscles
2. sensory neurons: transmit information from sensory organs to the brain
3. interneurons: communicate internally and transmit information between sensory and motor neurons
Neurons are specialized cells, but have same structures and functions of other cells
However, they are specialized for internal communication:
How do neurons work?
1. Electrochemical process
2. "firing of neuron" is called Action Potential
3. all or none principle
What triggers action potential?
1. resting potential (-70mV)
2. stimulation from other neurons open up channels to let in sodium ions (NA+)
3. if inside charge reaches threshold (-45mV) channels open wide and Na+ rushes in, changing internal charge to
+40 mV
What happens at axon terminal?
Synaptic transmission (neurotransmitters)
Synaptic transmission
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Steps:
1.
2.
3.
4.
5.
Synthesis
Release
Binding
Inactivation
Reuptake
Neurotransmitters
Acetylcholine (ACh)
-associated with memory, learning processes, and attention | main function movement | motor neurons release this
chemical
Other chemicals can affect synaptic transmission
Agonists: excite (work in similar way)
Antagonists: inhibit (work in opposite way)
Examples:
a) nicotine
b) curare
c) botulism (botox)
d) black widow spider venom
Dopamine
-related to movement, associated with learning and rewarding scenarios
Norepinephrine
-associated with things that keep you alert
-arousal, alertness
Serotonin
-implicated in mood disorders (anxiety), associated with sleep, mood
-one of the only neurotransmitters that is solely inhibitory
-slows the system down (for anxiety, seizure disorders)
Inhibitory: making it less likely for the next neuron to fire
Glutamate
-the most frequent neurotransmitter
-related to the memory system
Endorphins
-diminishes pain | a natural opiate drug
Ex: a runner's high
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The Nervous System
The Peripheral Nervous System
A. cranial nerves and spinal nerves
B. communication line between the central nervous system and the rest of the body
Somatic division: consciously controlling movement
ex: picking up your feet
Autonomic division: smooth muscles and movements you do not have control over
ex: your heart
Sympathetic and Parasympathetic branches
Sympathetic: fight or flight response
Parasympathetic: slows down, recovers from the fight or flight response
The Central Nervous System
A. brain and spinal cord
B. control centers
How do we study the brain?
1. natural damage -> resulting deficits
2. electrical stimulation and brain mapping
3. neuroimaging: MRI, CAT scan
4. animal studies
Hindbrain
Medulla:
-governs breathing and reflexes
-if damaged, more than likely you will die
-controls heartbeat and breathing
Thalamus:
-sight, sound, touch, hearing, taste, all beside smell travel through the thalamus
-relays info between lower and higher brain centers
-2 of them one on the left one on the right
-sensory relay station
Pons:
-governs sleep and rousal
-transmitter of motor information
-associated with the coordination between our left and right
Cerebellum:
-often referred to as the "little brain"
-helps with our balance
-involved in motor coordination
Reticular Formation:
-associated with general arousal, sleep
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Limbic system
-associated with really strong emotional reactions, sexual activity, learning and memory
Hippocampus:
-associated with memory, memory of things we have done
-related to the process of memories, that's where they are stored
-when damaged, you can't form new memories
Hypothalamus:
-one of the most important structures of the brain
-works with others, but has a role in your hunger drives, thirst drives, temperature regulation, and your
sex drive
-biological needs
-controls the pituitary gland
Controls the 4 F's:
-fighting
-fleeing
-feeding
-fucking
Amygdala:
-associated with aggression and fear responses
-related to emotions
Pituitary Glands
-sends out hormones to all the other glands
Cerebrum
-cerebral cortex: outer covering - 3mm
-divided into 2 hemispheres (left and right)
-hemispheres connected by a tissue called the Corpus Callosum
Each hemisphere consisted of 4 lobes:
1. frontal lobe (front of head)
-primary motor cortex
-sends a direct signal to move this part of your body
-cognition recent memory, planning of movement, and some aspects of emotion
2. temporal lobe (sides of head)
-primary auditory cortex
-hearing and advanced visual processing
3. parietal lobe (top of head)
-primary somatosensory cortex
-body sensation
4. occipital lobe (back of head)
-primary visual cortex
-vision
Damage to association area
Aphasia: language (speech) problems
a) Broca's area
b) Wernicke's area
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Hemispheric Specialization
Left: language, logical reasoning, math computations
Right: spatial relations, pattern recognition, music, emotional expression
-anything on the left visual, is getting processed by the right hemisphere and vice versa
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Exam 1Prescientific Psychology (Lecture 1)• Socrates (469-399 BC), mind and body
•
Plato (427-347 BC), mind and body, Socrates student
•
Aristotle (384-322 BC), Platos student, Dualistic thing doesn’t exist, separate, born with
nothing, mind is like blank slate, get knowledge gained thru experience
•
Descartes, Rene (1595-1650), Mind and body dualism, mind and body 2 separate
entities, Mind spiritual entity -Pineal Gland Body Material Entity,
Innate Ideas- Concepts of self and God,
Rationalism- Knowledge should be sought through the process of logical reasoning
•
Locke (1632-1704), Aristotle’s Tabula Rasa- mind as a blank slate waiting to be written
on by experience
Empiricism- all ideas and knowledge are gained empirically (through experience)
knowledge should be sought thru observation
Psychology Born•
Wilhelm Wundt (1879)- opened first psych lab in Leipzig, Germany, “atoms of the mind”
•
Edward Titchener- Wundt student, Structuralism- Early school of psych discover basic
elements of human mind, Introspection= “looking inside”
•
Functionalism- William James, school of psych focused on functions of mind and
behavior in adapting to the environment
What is Psychology?
• Until 1920’s Science of mental life
• 1920-1960 Science of Observable Behavior
• Today science of behavior and mental processes
Behavior is any action we can observe and record
Mental processes are private events inferred from behavior
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The Science of Psychology (Lecture 2)Research in Psych- Ethics•
Is it ethical to experiment on people (and animals)?
Research with Humans• Most Psychological research involves no stress
• Ethical principles developed by APA- 2010 (American Psychological Association)
• Universities screen research proposals through an ethics committee (Institutional Review
Board IRB)
Important issues1. Informed consent✓ Potential participants are informed about procedures and risks that might be
involved
✓ Participants are told that they are free to withdraw from a study at any time and
for any reason
2. Confidentiality✓ Data should be kept confidential and when possible anonymous
3. Debriefing✓ After study has been completed, participants receive info about the study
(purpose, methods, etc.)
4. Deception✓ Occurs when participates are misled about nature of study
✓ Should only be used when no other feasible alternative is available- deception
should not harm participants
Research with Animals• Only about 5% of APA members use animals in their research
• 95% of animals used are rats, mice, rabbits or birds
• Before animal research can be conducted, I must be reviewed and approved
• Researchers weigh potential benefits to research against possible harm to animal
• Researchers avoid inflicting unnecessary pain
• There is a set of standards for housing, feeding and maintaining the well-being of
the animal subject
Why do psychologists use animals in research?
1. To learn about people!
✓ Some behavioral principles are similar across species, but some basic
behavioral phenomena can be studied simple in nonhumans
✓ Some experiments are permissible only with animals
2. To learn animals
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✓ To understand how different species, learn, think and behave
A Scientific AttitudeEmpirical QuestionsQuestions that can be answered by making objective observations
SkepticismAn explanation for a behavior is accepted only after other possible explanations have been ruled
out
Critical thinkingThinking that examines assumptions, discerns hidden values, evaluates evidence and assesses
observations
Scientific MethodIDEA
1. Theories- Series of statements about relationships between variables that, taken together,
attempts to explain some natural phenomenon
2. Personal experiences
3. Daily observations
4. Someone else’s work
HYPOTHESIS
DATA COLLECTION
DATA ANALYSIS
How we study behavior- Is Descriptive studies
Case Studies- A single person, a rare case event or an event that clearly exemplifies a
phenomenon is studied in detail
-Insights gained through a case study may also lead to the development of hypotheses that
can be tested using other methods
Surveys- Participants are asked a series of question about their behaviors, thoughts, or
attitudes
-Sample is the subset of the population
-Interviews
-Phone surveys
Electronic surveys (e-surveying)
-Written surveys
Naturalistic Observations- The behavior of people or animals is studied as it occurs in its
everyday natural environment
-Used when the researcher wants to describe and understand how people in a social or
cultural setting live, work, and experience in the setting
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Correlational Studies- Correlations: exists whenever 2 variables are associate or related to
each other in some fashion
-Positive correlation (AKA direct correlation): two things increase or decrease together
-Negative correlation: indicate an inverse relationship- as one thing increases, the other
decreases
-Correlation coefficient: indicates the strength and direction of correlation
-Important: Correlation does not imply causation.
✓ Pearson’s r ranges from -1.00 to +1.00
✓ R= 0.00 no relationship between variables
✓ R= +1.00 perfect positive correlation
✓ R= -1.00 perfect negative correlation
-Directionality problem
-Third variable problem
Experimentation- Investigates cause and effect relationships
-Important: Investigator manipulates the factors of interest, while holding constant other
factors
-Independent variable: The variable that is being manipulated
-Dependent variable: What is being measured
-Control condition: Serves as a comparison for the experimental condition
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The Neuron• Nerve cell
• 3 main parts:
a) Dendrites- Branching extensions that receive chemical messages and conduct them to
the cell body.
b) Cell Body- Contains the neuron’s nucleus (with DNA and typical nuclear organelles).
c) Axon- Take information away from the body cell to other neurons or to muscles or
glands.
-Action potential (“impulse”): occurs when chemicals contact the surface of the neuron
(changing the balance of ions) and a brief electrical charge travels down the axon
-Myelin Sheath: fatty tissue that covers the axon of some neuron and helps speed neural impulses
-Threshold- There is a certain level of stimulation that is required to trigger an action potential
-All or none principle: if the threshold is not reached, then no action potential will fire; if the
threshold is reached, an action potential (always the same size) will fire
NeurotransmittersSynapse: the junction between the axon tip of the sending neuron and the dendrite of the
receiving neuron. The tiny gap at this junction is called the synaptic gap.
-Neurotransmitters: Chemical messengers that traverse the synaptic gaps between neurons
Examples- Dopamine- influences movement, learning, attention and emotion
Serotonin- affects mood, hunger, sleep and arousal
Acetylcholine (Ach)- Enables action, learning and memory
Endorphins- “brain’s” natural painkiller: in response to pain, stress, and other vigorous exercise
-Reuptake: the process by which the sending neuron reabsorbs the excess neurotransmitters
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The Nervous System
Peripheral Nervous System (PNS)• Links the central nervous system with the body’s sense receptors, muscles and glands.
1. Somatic- Specializes in the control of voluntary movements and the communications of
information to and from the sense organs
2. Autonomic- Controls the parts of the body that function involuntarily without our
awareness
✓ Sympathetic- prepares body for defensive action
✓ Parasympathetic- Acts to calm the body after the emergency situation has been solved
Central Nervous System (CNS)
• Brain and spinal cord
1. Spinal Cord- Connects the peripheral nervous system to brain
2. Brain• Central Core- (The “old brain”)
a) Medulla- Unconscious functions (e.g., breathing, circulation)
b) Pons- Coordinates muscles integrates movements between the right and left
halves of the body. Involved in sleep and arousal
• Medulla + Pons = Brainstem
c) Cerebellum- Body balance. Involved in intellectual functions
d) Reticular Formation- Functions related to sleep, arousal, and attention
e) Thalamus- Messages from the senses are directed to higher brain regions
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Limbic Systema) Hippocampus- Involved in the storage of memories
b) Amygdala- Involved in aggression and fear
c) Hypothalamus- Maintain homeostasis. Regulates basic biological needs (e.g.
hunger, thirst)
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Cerebral Cortex- Where the highest mental functions, such as thinking and planning,
take place!!!!
a) Left Hemisphere- Receives information only from the RIGHT side of the
body
Concentrates more on tasks that require verbal competence (speaking, reading,
thinking, and reasoning)
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b) Right Hemisphere- Receives information only from LEFT side of the body
Concentrates more in nonverbal tasks such as the understanding of spatial
relationships, recognition of patterns and drawings, music, ad emotional expression
Lateralization: The dominance of one hemisphere in specific functions
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The Cerebral cortex• How do we know about hemisphere specialization?
• Roger Sperry (1968) purposely legion area to stop seizures
• Corpus Callosum: Wide band of axon fibers that connects the 2 hemispheres
• Split brain research
• Left concentrates more on tasks that require verbal competence (speaking, reading,
thinking and reasoning) sees ball on right says ball
• Right concentrates more on nonverbal tasks such as the understanding of spatial
relationships, recognition of patterns and drawings, music and emotional expression
sees hammer from left so is able to draw but not say what it is
*Each hemisphere is subdivided into 4 regions:
• Frontal lobe
• Parental lobe
• Occipital lobe
• Temporal lobe
Functions of the Cerebral Cortex1. Motor Functions• Fritsch and Hitzig (1870) Experiments w/ dogs
• Wilder Penfield (1930s) Surgeries to stop cerebral palsy, mapped the motor cortex
using wide-awake patients
2. Sensory Functions• Wilder Penfield (1930s) mapped the sensory cortex
3. Higher mental functions (e.g. learning, remembering, thinking, and speaking)• Association areas
4. Language• Broca’s area- controls language and expression
• Wermicke’s area- controls language reception
Aphasia: inability to sue or understand written or spoken language
• Broca’s Aphasia difficulties in controlling the actual production of words
• Wernicke’s Aphasia difficulties in understanding the meaning of words
Frontal Lobe-
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• Control of voluntary movement
• Speaking
• Personality
• Making plans and judgement
-Lesions to the Frontal Lobe example Phineas Gage, survived metal bar to end, as he got better
his personality started to change, went from easy going, too hard to handle (1948)
Parietal Lobe• Receives sensory input for touch and body position
• Attention
• Spatial location
Occipital Lobe• Receives visual information from the visual fields
Temporal Lobe• Hearing
• Language processing
• memory
Sensation & PerceptionHow do we contrast our representations of the external world?
1. Detect physical energy from environment
2. Physical energy is encoded as neural signals
3. Information is selected, organized and interpreted
Sensation: allows the nervous system to receive and represent stimulus energy from our
environment
Perception: organizes and interprets sensory information
Which information do we extract from the environment?
We detect from the environment the information that we need to function and survive
We detect what are, for us, the important features of the environment
Psychophysics- area of psychology that studies the relationships between the physical
characteristics of stimuli, such as their intensity, and our psychological experience of them.
Threshold1. Absolute ThresholdThe lowest intensity at which a stimulus can be detected 50% of the time
Subliminal Stimulus: stimulus that is so weak or brief that although it is received
by senses, it cannot be perceived consciously
2. Difference Threshold (aka just noticeable difference)-
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The smaller difference between two stimuli that people can perceive 50%
of the time
The difference threshold increases with the magnitude of the stimulus
Weber’s law- to be perceived as different, two stimuli must differ by a
constant minimum percentage rather than a constant amount
Example: Lights: 8 % difference in intensity, Weight: 2% difference,
Tones: 0.3% difference in frequency
Sensory Adaption• Diminished sensitivity to an unchanging stimulus
• Adaption occurs in all sensory modalities
• Adaption allows our senses to pick up informative changes in the environment that could
be important to our well-being or survival
How do we “see” the world?
1. Light enters the eyes through the cornea (front of eye)
2. Light passes through the pupil (opening/ gap) amount of light that passes is regulated by
the iris
3. Lens helps focuses the incoming rays into an image on the retina
4. Light energy is converted into neural impulses and sent to the brain,
rods: retinal receptors that detect black, white and gray (on side) (120 million in eye)
(high sensitivity to dim light) (not color sensitive)
cones: receptor cells that detect fine, fine detail ad give rise to color sensations, (center),
(6 million in eye) (low sensitivity to light) (color sensitive), pigeons and chipmunks have
only cones in their retina- so they have color vision but very poor night vision!!!!
Optic nerve: carries the information to the brain
How do we “see” the colors?
Light Wavesamplitude: determines brightness
Wavelength: determines hue
Example: yellow flower to human, bee sees dark blue in the middle light blue on outside
so they can see where pollen is
Theories• Young- Helmholtz trichromatic theory
• Hering’s opponent-process theory
• Dual-process theory
Young-Helmholtz trichromatic theory• Individual cones are most sensitive to wavelengths that correspond to either blue, green,
or red
• What about yellow?
-red+green-pure color?
-red-green color-blind people
Hering’s opponent-process theory-
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Each of the three cone types responds to 2 different wavelengths
Red or green
Blue or yellow
Black or white
Dual-process theory• Combines the trichromatic and opponent-process theories
• Retina: Red, green and blue color cones
• Nervous system: signals are processed by opponent-process cells
Hearing• Sound waves
• Amplitude-determines loudness
• Wavelength- determines pitch
• Frequency rage- humans –20 to 20000 Hz
• Loudness- humans –absolute threshold: 0 decibels
How do we translate sound energy into neural messages?
• Sound waves pass through the auditory canal to the ear drum
• Ear drum vibrates and this vibration is transmitted to the cochlea (through the hammer,
anvil and stirrup)
• The vibrations cause the oval window (cochlea’s membrane) to vibrate jostling the fluid
that fills the tube
• This motion causes ripples in the basilar membrane, which is lined with hair cells
• The movement of these hair cells triggers impulses in the adjacent nerve fibers
Touch• Normally thought of as the detection of pressure against the skin
• Sense of touch is a mix of at least 4 distinct skin senses:
-Pressure
-Warmth
-Cold
-Pain
• Thermoreceptors- sense temperature changes at or near our skin
• Provide input to keep our body’s temperature regulation at 98.6 degrees F
• Warm and cold thermoreceptors
• Pain – is the sensation that warns us that damage to our bodies is occurring
• There is not a specific type of stimulus that triggers pain
• Nociceptors: sensory receptors that detect hurtful temperatures, pressure or chemicals
Smell•
Smell can provide us with important information:
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-Food choices
-Tracking
-Recognition
-Senses and emotions from the past
How do we smell things?
• Chemical molecules reach receptors at the top of the nose and then these receptors and
messages to the brain
• How good are humans at recognizing smells?
-Human olfactory system can be improved
• Smell fingerprint?
• Hard to recall odors by name
Taste• Like smell it is a chemical sense
• Taste sensations:
-sweet
-sour
-salty
-bitter
-umami?
-elicited by glutamate
• Not only taste buds are involved in taste
• Sensory interaction: one sense may influence another, as when the smell of food
influences its taste
Perception• Is active, creative process in which raw sensory data are organized and given meaning
• How do we organize and interpret our sensations so they become meaningful
perceptions?
Gestalt Principles of perception Organization• We have tendency to integrate pieces of information into meaningful wholes
• The wholes we perceive are often more than the sum of their parts
• Figure-ground relations: Focal stimulus is perceived as a figure against a background of
other stimulus
Gestalt Laws of perceptual organization:
• Law of Similarity- we tend to group together figures that are similar to each other
• Law of Proximity- Elements that are near each other are likely to be perceived as part
of the same configuration
• Law of Closure- We tend to fill gaps to create a complete, whole object
• Law of Continuity- We tend to link individual elements together so they form a
continuous line or pattern that makes sense
Depth perceptions-
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We seem to have an innate ability to perceive depth
Binocular cues: cues that depend on the use of 2 eyes
1. Retinal disparity: each eye sees a slightly different image,
-the greater the disparity (difference) the closer the object
2. Convergence: the extent to which the eyes converge in ward
-the greater the inward strain, the closer the object
Monocular cues:
1. Relative size: if 2 objects ae assumed to be similar size, we perceive the one that
cast the smaller retinal image as farther away
2. Interposition: if one object partially blocks our view of another, we perceive it as
closer
3. Relative height: we perceive objects higher in our field of vision as father away
4. Linear perspective: since parallel lines appear to converge with distance, the more
the lines converge, the grater their perceived distance
5. Relative motion: the farther away the object, the lower its apparent speed
6. Light and shadow: since nearby objects reflect more light to our eyes, given to
identical objects, smaller one seems farther away
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