Lectures experimental psychology
ISN 9781352004830
Lecture 1
Psychology → the scientific study of mind and behavior
- Mind → private inner experience of perception, thoughts, memories and feelings
- Behavior → observable actions of human beings and animals
Experiment → a technique of establishing a causal relationship between variables (independent
and dependent variable)
Focus on cognitive functions → all mental processes that lead to thoughts, feelings, memories,
knowledge, awareness, etc.
Cognitive processes → mechanisms that underlie cognition
Cognitive processes govern cognitive functions like attention, memory, learning,
decision-making, language, mental processing, perception, motor-skills, imagination, etc.
Cognitive functions are the ‘building blocks’ of all complex behavior → E.g. eating peas → this
task requires; perception, decision making, motor skills, attention, etc.
Experimental psychology is closely linked to cognitive (neuro)psychology
- Patients with (local) brain damage allow for more specific and reliable inferences about
brain functioning
- E.g. patients with neglect, aphasia (trouble producing or understanding speech), dyslexia,
visual agnosia (inability to recognize visual objects (but not faces)
Cognitive neuroscience → attempts to understand the biological foundations of cognition (the
main idea is that cognitive processes produce brain activity)
Nativism (rationalists)→ knowledge is innate or inborn, the knowledge is already there when
you are born (Spinoza, Leibniz and Descartes)
Dualism (Descartes is most known for this)→ the mind is not supreme, body and mind are
separate entities that interact (e.g. because bodily reflexes do not involve the mind/free will, the
body and mind must be distinct. Ex. ducking for a ball before it hits you)
Empiricists → knowledge is acquired (Locke, Berkeley, Hume)
Hermann von Helmholtz → first psychologist to conduct experiments. He studied, for example,
the conduction velocity of the nerve impulse/signals. How quickly does a signal travel in our
nervous system?
,Inspired by Weber, Gustav Fechner introduces the just noticeable difference (JND), which is still
widely used → minimum difference in stimulation that a person can detect 50% of the time
Franciscus Donders introduced mental chronometry → how much time do you need to decide
whether you heard the syllable ‘ka’, ‘ta’ or ‘pa’.
- Simple reaction time; press a button whenever you hear a syllable
- Differential/choice reaction time; press ‘k’ when you hear ‘ka’, ‘t’ when you hear ‘ta’,
etc. → you now have to discriminate, detect and make a decision
- Go/No go reaction time; press ‘k’ when you hear ‘ka’, but do nothing when you hear ‘ta’
or ‘pa’ → you have to detect and discriminate
Almost all experiments are build on this logic
Structuralism → consciousness should be the focus of study via analyses of the basic elements
that constitute the mind (Wilhelm Wundt)
- Achieved by breaking down consciousness into sensations and feelings via analytical
introspection → ex. Some melody is played to a participant. He will be asked what he
heard. "I hear tones of different duration, pitch and loudness (sensations), that are
structured in an unfamiliar rhythm which makes me feel confused (subjective
interpretation/feelings)”.
- Further developed by Edward Titchener who proposed 3 elementary states of
consciousness
1. Sensations → sights, sounds, tastes
2. Images → components of thoughts
3. Affections → components of emotions
And identified thousands of elemental qualities of conscious experience
Behaviorism (John Watson) → the introspective processes cannot be studied (too vague and
subjective) and overt behavior (what people do) should be studied instead because
- The only way to understand animal and human learning and adaptation is to focus solely
on their behavior
- Behavior can be observed by anyone and measured objectively
- The ghoul of scientific psychology is to predict and control behavior in a way that
benefits society
Behaviorism was part of the logical positivism movement utah introduced the operational
definition → a description of an abstract concepts or property in terms of a concrete condition
that can be measured
Abstract property; hunger
Condition; number of hours deprived from food
Abstract property; height of a person
Condition; Number of cm measured for feet to crown
,Operational definitions have big advantages as they allow for precise measurements and direct
comparisons between studies (replications)
But, operational definitions are not always good definitions (clear measurable conditions can still
be quite useless)
- Happiness is the number of smiles during a specific episode
- Age is the response that participants provide on a questionnaire
Ivan Pavlov → classical conditioning
- US = unconditioned stimulus (something that happens in the world) that produces an
- UR = unconditioned response
- When the US is repeatedly paired with another (neutral) stimulus, the other (neutral)
stimulus becomes a
- CS = conditioned stimulus that produces a
- CR = conditioned response which is the same as the UR but now occurs without the
original US
- Example with the dog, treat and saliva.
Skinner → operant conditioning → learning occurs
through reinforcement and punishment that can be
both positive (something is added) or negative
(something is removed)
Gestalt psychology (Wertheimer, Köhler, Koffka) → Key principle; the whole is more than the
sum of its parts. They use apparent motion to prove their point (phi phenomenon)
They rejected
- Wundt's structuralism (because experience is more than a function of sensation)
- Behaviorism, because complex behavior (“the whole”) is more than the sum of its
components
Perception is a construction, not a reflection of the sensation
Also in the auditory domain; you can either hear a galloping rhythm when 2 tones (high, high,
low are played, you hear 1 high stream and one low stream (especially when pith difference is
large)
Since 1970’s → cognitive revolution → computer is used as a metaphor for human thinking
, Since the 1980's → modern imaging techniques available like MRI. → testing
neuropsychological patients (single case and group studies) can help to answer theoretical
(general) hypotheses
- Functional MRI is about brain activity
Empiricism → acquiring knowledge requires observation
Scientific method → observations can lead to mistakes, false conclusions and illusions, so we
need a set of rules and techniques to avoid these
- theorize/generate an idea → often based on literature/work of other people/previous
experience. Use principle of parsimony/Occam's razor
- Formulate falsifiable hypotheses → if …. Is true, we should observe… (specific,
verifiable)
- Collect and analyze data → observations in a lab or in the real world, using specific
techniques. Operationalization should be concrete (many critical choices to make). Ex. do
we do this online, in the morning or afternoon, etc..
- Draw conclusions regarding the hypothesis → results align with hypothesis? Confirm
theory. Results do not align with hypothesis? Theory is wrong (falsification) or mistakes
in operationalization.
Deduction → drawing inferences based on premises, assumptions (general to specific)
- Premise ; all organisms die
- Premise; John is an organism
- Conclusion; John will die
Problem; we cannot observe all organisms to figure out whether or not they die so we must use
induction → specific to general;
- Premise; my dog died
- Premise; My tomato plant died
- Premise; etc.
- Conclusion; all organisms die
Problem; more observations cannot make a statement more true because unencountered
exceptions may arise (David Hume). Conclusion can only proven to be false (Karl Popper)
Humans are difficult to study
- Complexity; thoughts, feelings, action driven by 500 million neurons; not well
understood yet
- Variability; all else being equal, individuals are very different (I can ask what’s your
favorite meal for 3 days in a row and probably get the same answer, however if I ask you
in 2 years this might have changed)
ISN 9781352004830
Lecture 1
Psychology → the scientific study of mind and behavior
- Mind → private inner experience of perception, thoughts, memories and feelings
- Behavior → observable actions of human beings and animals
Experiment → a technique of establishing a causal relationship between variables (independent
and dependent variable)
Focus on cognitive functions → all mental processes that lead to thoughts, feelings, memories,
knowledge, awareness, etc.
Cognitive processes → mechanisms that underlie cognition
Cognitive processes govern cognitive functions like attention, memory, learning,
decision-making, language, mental processing, perception, motor-skills, imagination, etc.
Cognitive functions are the ‘building blocks’ of all complex behavior → E.g. eating peas → this
task requires; perception, decision making, motor skills, attention, etc.
Experimental psychology is closely linked to cognitive (neuro)psychology
- Patients with (local) brain damage allow for more specific and reliable inferences about
brain functioning
- E.g. patients with neglect, aphasia (trouble producing or understanding speech), dyslexia,
visual agnosia (inability to recognize visual objects (but not faces)
Cognitive neuroscience → attempts to understand the biological foundations of cognition (the
main idea is that cognitive processes produce brain activity)
Nativism (rationalists)→ knowledge is innate or inborn, the knowledge is already there when
you are born (Spinoza, Leibniz and Descartes)
Dualism (Descartes is most known for this)→ the mind is not supreme, body and mind are
separate entities that interact (e.g. because bodily reflexes do not involve the mind/free will, the
body and mind must be distinct. Ex. ducking for a ball before it hits you)
Empiricists → knowledge is acquired (Locke, Berkeley, Hume)
Hermann von Helmholtz → first psychologist to conduct experiments. He studied, for example,
the conduction velocity of the nerve impulse/signals. How quickly does a signal travel in our
nervous system?
,Inspired by Weber, Gustav Fechner introduces the just noticeable difference (JND), which is still
widely used → minimum difference in stimulation that a person can detect 50% of the time
Franciscus Donders introduced mental chronometry → how much time do you need to decide
whether you heard the syllable ‘ka’, ‘ta’ or ‘pa’.
- Simple reaction time; press a button whenever you hear a syllable
- Differential/choice reaction time; press ‘k’ when you hear ‘ka’, ‘t’ when you hear ‘ta’,
etc. → you now have to discriminate, detect and make a decision
- Go/No go reaction time; press ‘k’ when you hear ‘ka’, but do nothing when you hear ‘ta’
or ‘pa’ → you have to detect and discriminate
Almost all experiments are build on this logic
Structuralism → consciousness should be the focus of study via analyses of the basic elements
that constitute the mind (Wilhelm Wundt)
- Achieved by breaking down consciousness into sensations and feelings via analytical
introspection → ex. Some melody is played to a participant. He will be asked what he
heard. "I hear tones of different duration, pitch and loudness (sensations), that are
structured in an unfamiliar rhythm which makes me feel confused (subjective
interpretation/feelings)”.
- Further developed by Edward Titchener who proposed 3 elementary states of
consciousness
1. Sensations → sights, sounds, tastes
2. Images → components of thoughts
3. Affections → components of emotions
And identified thousands of elemental qualities of conscious experience
Behaviorism (John Watson) → the introspective processes cannot be studied (too vague and
subjective) and overt behavior (what people do) should be studied instead because
- The only way to understand animal and human learning and adaptation is to focus solely
on their behavior
- Behavior can be observed by anyone and measured objectively
- The ghoul of scientific psychology is to predict and control behavior in a way that
benefits society
Behaviorism was part of the logical positivism movement utah introduced the operational
definition → a description of an abstract concepts or property in terms of a concrete condition
that can be measured
Abstract property; hunger
Condition; number of hours deprived from food
Abstract property; height of a person
Condition; Number of cm measured for feet to crown
,Operational definitions have big advantages as they allow for precise measurements and direct
comparisons between studies (replications)
But, operational definitions are not always good definitions (clear measurable conditions can still
be quite useless)
- Happiness is the number of smiles during a specific episode
- Age is the response that participants provide on a questionnaire
Ivan Pavlov → classical conditioning
- US = unconditioned stimulus (something that happens in the world) that produces an
- UR = unconditioned response
- When the US is repeatedly paired with another (neutral) stimulus, the other (neutral)
stimulus becomes a
- CS = conditioned stimulus that produces a
- CR = conditioned response which is the same as the UR but now occurs without the
original US
- Example with the dog, treat and saliva.
Skinner → operant conditioning → learning occurs
through reinforcement and punishment that can be
both positive (something is added) or negative
(something is removed)
Gestalt psychology (Wertheimer, Köhler, Koffka) → Key principle; the whole is more than the
sum of its parts. They use apparent motion to prove their point (phi phenomenon)
They rejected
- Wundt's structuralism (because experience is more than a function of sensation)
- Behaviorism, because complex behavior (“the whole”) is more than the sum of its
components
Perception is a construction, not a reflection of the sensation
Also in the auditory domain; you can either hear a galloping rhythm when 2 tones (high, high,
low are played, you hear 1 high stream and one low stream (especially when pith difference is
large)
Since 1970’s → cognitive revolution → computer is used as a metaphor for human thinking
, Since the 1980's → modern imaging techniques available like MRI. → testing
neuropsychological patients (single case and group studies) can help to answer theoretical
(general) hypotheses
- Functional MRI is about brain activity
Empiricism → acquiring knowledge requires observation
Scientific method → observations can lead to mistakes, false conclusions and illusions, so we
need a set of rules and techniques to avoid these
- theorize/generate an idea → often based on literature/work of other people/previous
experience. Use principle of parsimony/Occam's razor
- Formulate falsifiable hypotheses → if …. Is true, we should observe… (specific,
verifiable)
- Collect and analyze data → observations in a lab or in the real world, using specific
techniques. Operationalization should be concrete (many critical choices to make). Ex. do
we do this online, in the morning or afternoon, etc..
- Draw conclusions regarding the hypothesis → results align with hypothesis? Confirm
theory. Results do not align with hypothesis? Theory is wrong (falsification) or mistakes
in operationalization.
Deduction → drawing inferences based on premises, assumptions (general to specific)
- Premise ; all organisms die
- Premise; John is an organism
- Conclusion; John will die
Problem; we cannot observe all organisms to figure out whether or not they die so we must use
induction → specific to general;
- Premise; my dog died
- Premise; My tomato plant died
- Premise; etc.
- Conclusion; all organisms die
Problem; more observations cannot make a statement more true because unencountered
exceptions may arise (David Hume). Conclusion can only proven to be false (Karl Popper)
Humans are difficult to study
- Complexity; thoughts, feelings, action driven by 500 million neurons; not well
understood yet
- Variability; all else being equal, individuals are very different (I can ask what’s your
favorite meal for 3 days in a row and probably get the same answer, however if I ask you
in 2 years this might have changed)
