History of Nature-Nurture Debate

History of Nature-Nurture History of Nature-Nurture DebateDebate

PlatoPlato Rationalist- serious Rationalist- serious

contemplation can contemplation can derive rational derive rational answersanswers

knowledge is knowledge is innateinnate gave rise to gave rise to

introspectionintrospection

AristotleAristotle Empiricist- observe Empiricist- observe

external causes of external causes of behaviorbehavior

gave rise to gave rise to materialism- materialism- experienceexperience is the is the source of knowledgesource of knowledge

how does the “soul/mind” how does the “soul/mind” give rise to memory, give rise to memory, sensation, movement, etc.sensation, movement, etc.

where is the “soul/mind” where is the “soul/mind” locatedlocated

““Mind-Body Problem”Mind-Body Problem” Decartes (1596-1650) was a Decartes (1596-1650) was a

RationalistRationalist Proponent of Proponent of DualismDualism: body : body

(material) and soul (material) and soul (immaterial) are independent(immaterial) are independent

Body acts according to laws Body acts according to laws of physicsof physics

Soul cannot be studied Soul cannot be studied (source of knowledge)(source of knowledge)

mechanistic view (e.g., reflexes)mechanistic view (e.g., reflexes) pineal gland as the interface pineal gland as the interface

between soul and bodybetween soul and body

HobbesHobbes

Hobbes (1588-1679) Hobbes (1588-1679) was an Empiricistwas an Empiricist Proponent of Proponent of MonismMonism: :

all we are can be all we are can be explained by physical explained by physical characteristicscharacteristics

Led to British Led to British Empiricists (18th Empiricists (18th Century)Century)

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are needed to see this picture.

British EmpiricistsBritish Empiricists

Supported method of Supported method of observation to study observation to study mental processingmental processing

John Locke - “Tabula John Locke - “Tabula Rasa”Rasa”

all thought can be all thought can be explained in terms of explained in terms of sensory experiencesensory experience



Industrial Revolution

Asylums became “theatre” Asylums became “theatre” for the rich (e.g. Bedlam for the rich (e.g. Bedlam (Bethlem and Maudesley))(Bethlem and Maudesley))

Un-scientific treatments Un-scientific treatments proposed e.g.proposed e.g. MHP is excess of blood, MHP is excess of blood,

therefore therefore Blood letting Blood letting Other “treatments”:Other “treatments”:

FrightFright Forced vomitingForced vomiting











BedlamBedlam





Phrenology: Franz Gall (1758-1828)







cranioscopy

MesmerMesmer

MagnetsMagnets "The workings of "The workings of

dilation and dilation and contraction of the contraction of the vessels, on the vessels, on the liquorliquor which they which they contain, is the contain, is the cause of animal cause of animal life."life."



HyponosisHyponosis







Towards Enlightenment:Humanitarianism and social revolution

Locke (late 1700’s) in UK proposed a “reasoning” argument for mental health problems

“madmen put wrong ideas together, and so make wrong propositions but argue reason right from them…”

Quaker movement in UK started retreats for the vulnerable for rest and some mild work

Pinel (1745-1826) in FranceIn line with egalitarian ideals of the French Revolution, proposed a Social theory of vulnerability, e.g.

Those with MHP were normal people who should be approached with compassion, as their reasoning was affected by severe personal and social problems…Added that institutionalising people “denying light and air” exacerbated their problems



Into the Victorian era

but social exclusion rather than humane interventions continued

J.S. Mill in 1859 warned of the danger to vulnerable people of being:

“in peril of a commission de lunatico, and of having their property taken away from them and given to their relatives”

Exacerbated by the Eugenic movement:“Discredited theory ranked human groups with…white Europeans at the top and people dwelling in their conquered colonies at the bottom” SJ GouldPeople with intellectual/physical disabilities or were mentally unwell were seen as “not fit” to fit in and, again, scapegoated

Fernauld “the feeble minded…[are] parasitic..never capable..most dangerous element in society”

Advances in understanding mental health (19c-20c)

A biological Approach:Kraeplin (1856-1926)

Proposed chemical imbalance (e.g. in metabolism) as causal of MHP

Established systems of classification according to medical knowledge not social prejudice e.g.

E.g. dementia praecox (later schizophrenia)Manic-depressive psychosisDelusions & general paresis (general weakness)

Advances in identification and treatment made e.g. syphilis is caused by germs, is transmitted, & can damage areas of brain, leading to delusions & general paresisIf treated early, does not lead to brain injury and MHP symptoms

Advances in understanding mental health (19c-20c)

A psychological Approach“biological” symptoms of psychological distress (psychogenic) described by Neurologists and PhysiciansCharcot (1825-1893) & Breuer (1842-1925)

A sub-group of adult patients with intermittent paralysis of limbs or loss of hearing could have episode triggered by precise discussion of early trauma

Foundations of psychoanalysis

Weber (1795-1878) Weber (1795-1878)

Weber studied perceptions of weight and tried Weber studied perceptions of weight and tried to relate these to actual physical weight.to relate these to actual physical weight. Weight is an objective physical property of Weight is an objective physical property of

objects.objects. The greater the weight, the greater the The greater the weight, the greater the

difference between a standard and comparison difference between a standard and comparison must be to be detectable.must be to be detectable.

Weber’s LawWeber’s Law -- Just-noticeable difference -- Just-noticeable difference (jnd) is a constant across sensory modalities.(jnd) is a constant across sensory modalities.

Fechner (1801-1887)Fechner (1801-1887)

Tried to relate physical properties to Tried to relate physical properties to psychological sensations:psychological sensations: Related the objective to the subjective.Related the objective to the subjective.

Fechner’s LawFechner’s Law – each JND corresponds to – each JND corresponds to one subjective unit of measure, with the one subjective unit of measure, with the relationship described mathematically.relationship described mathematically.

Credited with founding psychophysics.Credited with founding psychophysics.

The Same Color?The Same Color?

The Same Color?The Same Color?

Webber’s LawWebber’s Law

Sensing the World Around UsSensing the World Around Us

Absolute thresholdAbsolute threshold The smallest intensity of a The smallest intensity of a

stimulus that must be present stimulus that must be present for it to be detectedfor it to be detected

Contrast SensitivityContrast Sensitivity

0% 1% 2% 3% 4%

Backgroundconstant

Circleconstant

Just noticeable difference (JND) at 2%


0% 1% 2% 3% 4%

Backgroundconstant

Circleconstant

Just noticeable difference (JND) at 2%


0% 1% 2% 3% 4%

Backgroundsame as

right half

Backgrounddifferent thenboth halves

Just noticeable difference (JND): 4% (top) and 2% (bottom)


0% 1% 2% 3% 4%

Backgroundsame as

right half

Backgrounddifferent thenboth halves

Just noticeable difference (JND): 4% (top) and 2% (bottom)

Light 1 Light 2

Intensity = 10 W Intensity = 10 W

Light 1 Light 2


Brightness versus intensityBrightness versus intensity

standard light at fixed intensitystandard light at fixed intensity test light with adjustable intensitytest light with adjustable intensity adjust power of test until just begins to differadjust power of test until just begins to differ just noticeable difference: JNDjust noticeable difference: JND

Light 1 Light 2


Light 1 Light 2


Light 1 Light 2


Light 1 Light 2


Standard Test

A just noticeable difference (JND) at 11W

1 W above standard

Brightness versus intensityBrightness versus intensity


Forced-choice ResponseForced-choice Response

A bit more rigorousA bit more rigorous Q: brighter light on left or right?Q: brighter light on left or right?


















Analyse accuracy of response versus intensity of lightsAnalyse accuracy of response versus intensity of lights


Light 1 Light 2

Power = 10 W Power = 10 W

Brightness depends on Brightness depends on wavelengthwavelength

Light 1: at one wavelengthLight 1: at one wavelength Light 2: at different wavelengthLight 2: at different wavelength

Adjust power of second light until its brightness is the same as Adjust power of second light until its brightness is the same as the firstthe first

Light 1 Light 2





Light 1 Light 2





Light 1 Light 2


Light 1 Light 2


Light 1 Light 2


Light 1 Light 2





Simultaneous brightness contrast:Simultaneous brightness contrast:two squares of the same intensitytwo squares of the same intensity

Simultaneous brightness contrast:Simultaneous brightness contrast:left one looks brighterleft one looks brighter

Simultaneous brightness contrast:Simultaneous brightness contrast:pattern increases differencepattern increases difference

The Early Era and Roots of The Early Era and Roots of PsychologyPsychology

PsychophysicsPsychophysics Early psychologists, doing research on Early psychologists, doing research on

sensation and sensory experience, noticed sensation and sensory experience, noticed interesting aspects of the functioning of the interesting aspects of the functioning of the senses.senses.

For example, the perception of a stimulus’ For example, the perception of a stimulus’ intensity is not directly proportional to the intensity is not directly proportional to the actual physical intensity of the stimulus.actual physical intensity of the stimulus.


PsychophysicsPsychophysics A sound that is half as loud (in physical terms, A sound that is half as loud (in physical terms,

in decibels) as another sound may not sound in decibels) as another sound may not sound that way to the listener.that way to the listener.

Psychophysics attempts to provide a Psychophysics attempts to provide a mathematical description of the relationship mathematical description of the relationship between the actual physical properties of the between the actual physical properties of the stimulus and its perceived properties.stimulus and its perceived properties.

First Psychologists First Psychologists (late 1800s-early 1900s)(late 1800s-early 1900s)

–Wilhelm Wundt

father of experimental psychology

first psychology laboratory in Leipzig, Germany, 1879

studied reaction time to simple and two-choice stimuli

Wundt & EbbinghausWundt & Ebbinghaus

Wundt Wundt (1832-1920) organized psychology (1832-1920) organized psychology and helped to establish it as an independent and helped to establish it as an independent discipline.discipline. Wrote “Principles of Physiological Psychology”Wrote “Principles of Physiological Psychology” Did not believe higher mental processes Did not believe higher mental processes

(memory, thought, creativity) could be studied (memory, thought, creativity) could be studied experimentally.experimentally.

EbbinghausEbbinghaus (1850-1909) demonstrated that (1850-1909) demonstrated that memory could be studied experimentally.memory could be studied experimentally.

Stucturalism vs FunctionalismStucturalism vs Functionalism

Structuralism – focused on the contents of Structuralism – focused on the contents of mind.mind. Sensations, images (ideas), affectionsSensations, images (ideas), affections Used introspection to identify basic elements.Used introspection to identify basic elements. Introspection proved to be an unreliable Introspection proved to be an unreliable

method.method. Functionalism – focused on the adaptive Functionalism – focused on the adaptive

function of psychological processes within function of psychological processes within a context.a context. Not much experimental work done.Not much experimental work done.

Wilhelm Wundt Wilhelm Wundt originated one of originated one of the most famous the most famous forms of forms of introspectionism, introspectionism, called called structuralism.structuralism.

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StructuralismStructuralism

The structuralists tried to examine as The structuralists tried to examine as closely as possible their responses to closely as possible their responses to stimuli.stimuli.

They believed that one could by careful They believed that one could by careful introspection isolate and discover the introspection isolate and discover the building blocks of conscious building blocks of conscious experience.experience.









Wundt and StructuralismWundt and Structuralism Reaction times Reaction times (duration of apperception)(duration of apperception) IntrospectionIntrospection

Thinking About ThinkingThinking About Thinking Extensive training (10,000 observations)Extensive training (10,000 observations) 4 dimensions 4 dimensions (quality, intensity, duration, clarity)(quality, intensity, duration, clarity)

Limitations:Limitations: Different Observers Arrive at Different ResultsDifferent Observers Arrive at Different Results Alters the Experience.Alters the Experience.

Difficulties with IntrospectionDifficulties with IntrospectionThree of the biggest problems with Three of the biggest problems with

introspection are:introspection are: that even when people are trying to that even when people are trying to

answer accurately, some processes are answer accurately, some processes are non-introspectable. non-introspectable.

Further, people differ in their degree of Further, people differ in their degree of introspective ability. introspective ability.

Finally, most introspections are Finally, most introspections are impossible to verify. impossible to verify.

Structuralism in “New World”Structuralism in “New World”

Edward Titchener (1867 - 1927)Edward Titchener (1867 - 1927) Studied in Wundt’s labStudied in Wundt’s lab Popularized his Methods in U.S.Popularized his Methods in U.S. Opened a lab at Cornell UniversityOpened a lab at Cornell University School of Thought Called School of Thought Called StructuralismStructuralism







Tools of the tradeTools of the trade









FunctionalismFunctionalism

William James (1842-1910)William James (1842-1910) First major American Psychologist.First major American Psychologist. Combined method of introspection with direct Combined method of introspection with direct

observation.observation. Studied how the mind helps us adapt to the Studied how the mind helps us adapt to the

environmentenvironment Opposed to StructuralismOpposed to Structuralism Influenced by Darwin (adaptability)Influenced by Darwin (adaptability)


The enormous impact of Darwin: The origin of species The enormous impact of Darwin: The origin of species (1859); The descent of man (1871)(1859); The descent of man (1871) In his presentation of compelling evidence that humans In his presentation of compelling evidence that humans

and other animal species were related, and other animal species were related, Charles DarwinCharles Darwin forced scientists and thoughtful people working in forced scientists and thoughtful people working in many disciplines to consider the basic features held in many disciplines to consider the basic features held in common by many or all animals, such as thinking and common by many or all animals, such as thinking and intelligence.intelligence.

Comparative psychologistsComparative psychologists, who use this perspective, , who use this perspective, are specialists who compare different animal species.are specialists who compare different animal species.

DarwinDarwin

““the Origin of th the Origin of th Species”Species”

EvolutionEvolution







The First PsychologistsThe First Psychologists

–William James first important textbook: The Principles of Psychology

the mind is a stream of consciousness

William JamesWilliam JamesPrinciples of PsychologyPrinciples of Psychology

““We know of nothing … which can be in the remotest We know of nothing … which can be in the remotest degree compared with the degree compared with the stream of thought stream of thought that that accompanies the brain’s material accompanies the brain’s material

secretions.”secretions.”

http://psychclassics.yorku.ca/index.htmhttp://psychclassics.yorku.ca/index.htm

Early Contributions of WomenEarly Contributions of Women

Mary Calkins (1863-1930)Mary Calkins (1863-1930) Developed important technique for studying Developed important technique for studying

memory.memory. First woman president of APAFirst woman president of APA..

Many other accomplished women played Many other accomplished women played a role in the early history of Psychology.a role in the early history of Psychology.

Outside Report: Outside Report: BehaviorismBehaviorism

Behaviorism is rather an antithesis to Behaviorism is rather an antithesis to introspectionism introspectionism

John Watson, the John Watson, the founder of founder of Behaviorism, was Behaviorism, was solely interested solely interested in observable in observable behavior. The behavior. The question is question is always “What always “What behavioral behavioral evidence . . . ?” evidence . . . ?”





More than that, though, it is also the position that More than that, though, it is also the position that one should only study the relationship between one should only study the relationship between a stimulus and a behavior. a stimulus and a behavior.

““Psychology as the Psychology as the behaviorist behaviorist views it is a views it is a purely objective branch of natural science. purely objective branch of natural science. Its theoretical goal is the prediction and Its theoretical goal is the prediction and control of behavior. Introspection forms no control of behavior. Introspection forms no essential part of its methods, nor is the essential part of its methods, nor is the scientific value of its data dependent upon scientific value of its data dependent upon the readiness with which they lend the readiness with which they lend themselves to interpretation in terms of themselves to interpretation in terms of consciousness. The behaviorist, in his consciousness. The behaviorist, in his efforts to get a unitary scheme of animal efforts to get a unitary scheme of animal response, recognizes no dividing line response, recognizes no dividing line between man and brute” (Watson, 1913, p. between man and brute” (Watson, 1913, p. 158). 158).

As it will turn out, it is difficult to fully describe As it will turn out, it is difficult to fully describe every psychologically interesting property every psychologically interesting property solely in terms of behavior. solely in terms of behavior.


Women in PsychologyWomen in PsychologyIn the early days of psychology, In the early days of psychology, opportunities for women were opportunities for women were limited. limited.

Mary CalkinsMary Calkins was one of the was one of the pioneering women in the field.pioneering women in the field.

She never received the Ph.D. that She never received the Ph.D. that she earned from Harvardshe earned from Harvard

She went on to do research, study She went on to do research, study the function of memory, and the function of memory, and serve as the president of the serve as the president of the American Psychological American Psychological Association 1905.Association 1905.


Women in PsychologyWomen in Psychology Other early contributing women in the field of psychology were:Other early contributing women in the field of psychology were:

Christine Ladd-Franklin –color visionChristine Ladd-Franklin –color vision Margaret Washburn -first woman to receive Ph.D.Margaret Washburn -first woman to receive Ph.D. Karen HorneyKaren Horney Anna FreudAnna Freud

The latter two were followers of Sigmund Freud and the The latter two were followers of Sigmund Freud and the Psychoanalytic school of psychology.Psychoanalytic school of psychology.

Ethnic Minorities in PsychologyEthnic Minorities in Psychology

Gilbert Jones - 1901, First black male Ph.D.Gilbert Jones - 1901, First black male Ph.D. Inez Possner - 1933, First black female Ph.D.Inez Possner - 1933, First black female Ph.D. Kenneth Clark – 1971, First Black president Kenneth Clark – 1971, First Black president

APAAPA Norman Anderson – 2002, First Black CEO Norman Anderson – 2002, First Black CEO

APAAPA


Behaviorism – John B. Watson and B.F. SkinnerBehaviorism – John B. Watson and B.F. Skinner structuralism was abandoned because it was difficult to structuralism was abandoned because it was difficult to

study the subjective perception of experience.study the subjective perception of experience. BehaviorismBehaviorism concentrates on observable, measurable concentrates on observable, measurable

behaviors and not mental processes.behaviors and not mental processes. Behaviorists primarily seek to study the observable Behaviorists primarily seek to study the observable

behaviors associated with learning.behaviors associated with learning.


Behaviorism – John B. Watson and B.F. SkinnerBehaviorism – John B. Watson and B.F. Skinner

““Psychology as the behaviorist views it is a purely objective Psychology as the behaviorist views it is a purely objective experimental branch of natural science. Its theoretical goal is the experimental branch of natural science. Its theoretical goal is the prediction and control of behavior.” -- John B. Watson, 1913prediction and control of behavior.” -- John B. Watson, 1913

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History of Nature-Nurture Debate