19th Century

The Science of Psychology

Johann Friedrich Herbart 1776 – 1841 Textbook in Psychology (1816) Psychology as a science, newly founded

upon experience, metaphysics and mathematics (1824)

Although thought the mind could not be studied experimentally (the mind acts as an integrated whole which could not be fractionated), he believed that the mind could be explained mathematically

Provided no room for innate ideas or a priori concepts

Instead, the elements of consciousness (and unC) are to be understood in terms of the dynamical, mechanical laws of physics and so are subject to be understood via mathematics

Johann Friedrich Herbart For Herbert, ideas had a force or energy of

their own (a la Leibnizian monads) and so the laws of association were not necessary to bind them

His system, referred to as psychic mechanics, proposed that ideas had the power to attract or repel other ideas, depending on their compatibility

Ideas attempt to gain expression in consciousness and compete with each other to do so

Johann Friedrich Herbart At any given moment a group of compatible

ideas are in consciousness and constitutes the apperceptive mass, that to which we are attending.

Ideas outside the apperceptive mass (incompatible ideas) will be repressed by the powers of the ideas in the mass.

He used the term limen (anticipating Fechner’s JND) to describe the threshold between conscious and unconscious and his goal was to mathematically express the relationships among the apperceptive mass, the limen, and the conflict among ideas.

Johann Friedrich Herbart He applied his ideas to education by

offering suggestions on how to teach effectively: 1) Review the material already learned 2) Prepare the students for new material by

giving overview of upcoming material 3) Present the new material 4) Relate the new material to what has already

been learned 5) Show applications of the new material and

give an overview of next material to be learned

Hermann von Helmholtz 1821-1894 Considered to be one of the

greatest scientists of the 19th century because of his contributions to the fields of physics, physiology, and eventually psychology

Paved the way for the emergence of experimental psychology

Helmholtz Disagreed with the concept of vitalism which

states that life comes from a force beyond physical and chemical processes alone Because it was not physical the “life force” was

not conducive to scientific analysis. The materialist position (Helmholtz and

others) stated that life could be explained in terms of physical and chemical processes and thus there is no need to exclude the study of life or anything else from the realm of science

Hermann von Helmholtz Through research he was able to

demonstrate the application of the principle of conservation of energy to living organisms Energy can be converted from one form to

another, but it cannot be created or destroyed Helmholtz measured the speed of nerve

conduction, finding that nerve conduction in humans to be between 165 to 330 feet per second This provided further evidence that physical-

chemical processes are involved in our interactions with the environment rather than some mysterious process

Hermann von Helmholtz Theory of Perception For Helmholtz, sensations are raw elements

of experience, and perception is the sensation after being given meaning by the person’s past experience

To explain the transformation from sensation to perception he relied on the ideas of unconscious inference of past experience Humian notion

Also introduced the concepts of stereopsis and perceptual learning

Hermann von Helmholtz He devised a theory of color vision which proposed

three types of color receptors corresponding to the three primary additive colors

Trichromatic theory The firing of these receptors in various combinations

results in subjective color experiences corresponding to various wavelengths of light

He also proposed a resonance place theory of auditory perception in which the pitches of sound we hear are determined to a great extent on where along the basilar membrane the most vibration is occurring in response to a sound vibration

Hermann von Helmholtz Helmholtz vs. Kant Helmholtz disagreed and thought the

categories were derived through experience

Suggested that if our experience were different, even our (supposedly innate) mathematical axioms would be different

However did agree that the perceiver determined the nature of sensation (however due to past experience rather than innate categories)

Christine Ladd-Franklin 1847-1930 Psychologist, logician, mathematician First woman student to enter Johns

Hopkins But no PhD because she was an icky girl with

cooties! Worked in Helmholtz's laboratory Proposed a theory of color vision which

was based on evolutionary theory and the evolution of the physiology of the system

Achromatic first developed, color later, and color vision itself developed over time

Ernst Weber

1795-1878 Physiologist

interested in sense of touch and kinesthesis (muscle sense)

The Just Noticeable Difference

Ernst Weber Investigated the sense of touch and mapped

out the sensitivity of touch for the entire body using the two-point threshold

Smallest distance between two points for them to be perceived as such (instead of one)

Sensitivity ranged from the most sensitive on the tongue to least sensitive on the back

His work in kinesthesis led to the determination of the just noticeable difference (JND), the least amount of change necessary to notice a difference along a particular dimension between two stimuli

Ernst Weber With his research he was able to determine

Weber’s law (or Weber-Fechner law) – the finding that the amount of change necessary to notice a difference (JND) is a constant fraction of the type of stimulus under investigation

E.g. lifted weights: 1/40 of reference weight This was the first quantitative law in psychology

The relationship between stimulus and perception Perception a function of stimulus intensity and not

based on absolute differences between stimuli, but relative difference

Gustav Fechner 1801-1887 Psychophysics

Study of the relationship between the body and the mind

Elemente der Psychophysik

Gustav Fechner Early work (more than 40 works

published by 30) included efforts in physics and mathematics

Turned to more psychological topics and at one point studied afterimages, for which he needed a bright stimulus

He chose the sun Subsequently injured his eyes, fell ill

and suffered major depression, resigned post at Leipzig

Gustav Fechner

Recovered rather suddenly about three years later and became deeply religious

Renounced his former materialism and turned to poetry and metaphysics

Eventually became interested in the problem of the psychological-physical relationship

Gustav Fechner Sought to express the relationship between

mental and physical events His research and further mathematical

workings with Weber’s law resulted in Fechner’s formula describing the relationship

He speculated that for mental sensations to change arithmetically the physical stimulus must change geometrically

S = k log R S is the sensation, k is a constant, and log R the

logarithm of the physical intensity of the stimulus He had shown that under proper laboratory

conditions reliable data regarding psychological phenomenon could be collected

Gustav Fechner His further research included studies on the

absolute threshold – the lowest intensity at which a stimulus can be detected, and the difference threshold – the amount a stimulus magnitude that needs to be changed before a person detects a difference

In studying these psychophysical measures Fechner developed various methods of research

Method of limits Standard plus varying stimulus that is presented in greater

(or lesser) amounts; find the range that equals the standard or look for absolute thresholds

Method of constant stimuli Standard plus varying stimulus that is presented randomly

Method of adjustment Subject varies; average difference between variable

stimulus and standard noted

Gustav Fechner Developed a doctrine of panpsychism Panpsychism is the doctrine that

mind, in some sense of the term, is everywhere

Fechner's panpsychism carried with it the notion of a “world-soul” or “world-mind” of which everything is a part Recall Spinoza

Gustav Fechner Other stuff Psychophysical techniques still employed (now

with catch trials) Later turned his attention to aesthetics to

determine what leads to a judgment of beauty Analyzed 20,000 paintings from 22 museums

Predicted that if the corpus callosum were split, consciousness would as well

W. James being foolish: “Fechner’s book was the starting point for a new

department in literature, which it would be impossible to match for the qualities of thoroughness and subtlety, but of which, in the humble opinion of the present writer, the proper psychological outcome is just nothing.”

Early Approaches to Psychology

The New Science

Early Approaches to Psychology At this point in time the modern Psychology was

ready to be a full-fledged science Others had been advocating it as a separate

endeavor and did everything to promote it as such without actually engaging in the science itself

Bain Spencer

Still others were engaging in the research but more from the realm of physics or physiology proper

Helmholtz Weber

Wilhelm Wundt 1832-1920 The founder of psychology First lab devoted exclusively to the

study of psychology proper 1879 Sorry James, but no

Wundt took the diverse achievements of others and himself and synthesized them into a unified program of research

Psychology’s first school (group of individuals who share common assumptions, work on common problems, and use common methods) was formed

Voluntarism

Wilhelm Wundt With Helmholtz and Fechner paving the way,

Wundt had both a reason and a means for attempting the scientific study of psychology

However he was not wed to the previous, sometimes dualist, sometimes strictly empirical, approaches of his predecessors

For him, the subject matter of psychology was the “manifold of consciousness”, to be studied by means of experimental psychology

Includes more than the interpretation of the objects of sense, but also emotion, imagery, memory, attention etc.

Wilhelm Wundt ““Mind,” “intellect,” “reason,” “understanding,” etc.,

are concepts... that existed before the advent of any scientific psychology.  The fact that the naive consciousness always and everywhere points to  internal experience as a special source of knowledge, may, therefore, be accepted for the moment as sufficient testimony to the right of psychology as a science... “Mind,” will accordingly be the subject to which we attribute all the separate facts of internal observation as predicates.  The subject itself is determined wholly and exclusively by its predicates.”

What the mind does is the object of study Psychology proper is synonymous with physiological (in

this sense the causal laws governing mind) and experimental psychology

Wilhelm Wundt Note however that Wundt was in no way a

strict materialist or reductionist Mind could not simply be reduced to matter He early on recognized the failures of both

previous dualistic and monistic forms of arguments, and that the recent technological developments would not solve the issue

Furthermore, for Wundt it was not psychology’s place to do so either

Wilhelm Wundt Psychology’s goal was to understand

both simple (basic processes of the mind) and complex (higher mental processes) conscious phenomena

For simple phenomena experimentation was to be used, for complex phenomena experimentation could not be used – only various forms of naturalistic observation could be used

Wilhelm Wundt For Wundt, there were two types of

experience Mediate experience and data are

obtained via measuring devices and thus are not direct

Immediate experience and data are events in human consciousness as they occurred

This was to be the subject matter of psychology

Wilhelm Wundt He and his assistants used a variety of methods but

primarily ‘introspection’ However his experimental introspection was not the

unstructured self-observation used by earlier (and some later) philosophers/“psychologists”

Pure introspection Wundt’s introspection used laboratory instruments to

present stimuli, in most instances the subject was to respond with a simple response such as saying “yes” or “no”, pressing a key

Experimental introspection In his research he also used a method developed by

Franciscus Donders to measure differences in reaction time when various mental activities were required by the experimental situation

Mental chronometry

Wilhelm Wundt There are two basic types of mental

experience, sensations and feelings Sensations occurred when a sense organ is

stimulated and the impulse reaches the brain These can be described in terms of modality,

intensity, and quality Feelings accompanied sensations and could

be described along three dimensions, pleasantness – unpleasantness, excitement – calm, and strain – relaxation

Tridimensional theory of feelings

Wilhelm Wundt For Wundt, perception is a passive process

governed by the stimulation present, the physical makeup of the person, and the person’s past experience

The interaction of these factors makeup the person’s perceptual field and the part of this field the person attends to is apperceived, apperception and selective attention are the same

Apperception is active and voluntary The active role of attention

Elements which are attended to can be arranged and rearranged according to the person’s will, thus arrangements not experienced before can be produced

‘creative synthesis’

Wilhelm Wundt Distinguished between physical and

psychological causality Wundt believed that physical causality

is a reality because events could be predicted on the basis of antecedent conditions, but psychological causality was not possible

Can’t predict volition as it is due to unconscious (though deterministic) influences

Wilhelm Wundt Though he did not believe that higher mental

processes could be studied experimentally, they were reflected in human culture

The nature of the higher mental processes could be deduced from the study of such cultural products as religion, social customs, myths, history, language, morals, art, and the law

Recall Comte Wundt’s twenty year study of these things

culminated in his 10-volume work, “Folk Psychology”

Wilhelm Wundt

Some of Wundt’s students Cattell Titchener Witmer Munsterburg Spearman Hall

Titchener 1867-1927 For Titchener the goals of

psychology were the determination of the what, how, and why of mental life

The what was learned through introspection – the cataloging of the basic mental elements that make up conscious experience

The how answered the question of how the elements combined

The why involved the neurological correlates of mental events

As psychology was the experimental analysis of consciousness, he sought to describe mental experience – the structure of the mind

Hence the school was called structuralism

*Wundt was not a structuralist in the sense his student Titchener was. Cognition was more than the sum of its parts.*Wundt was not a structuralist in the sense his student Titchener was. Cognition was more than the sum of its parts.

Titchener “When we are trying to understand the mental processes of a child or

dog or an insect as shown by conduct and action, the outward signs of mental processes,… we must always fall back upon experimental introspection… we cannot imagine processes in another mind that we do not find in our own. Experimental introspection is thus our one reliable method of knowing ourselves; it is the sole gateway to psychology”

Note that in this light a metaphysical claim is made that on the nature of psychology, i.e. psychology is a method, its subject matter would involve only that which was amenable to that method

Titchener Titchener’s introspection was more complicated

and required more of the subject than Wundt’s “The general rules of introspection are as follows: be

impartial, be attentive, be comfortable, be perfectly fresh.”

Introspection in Titchener’s laboratory required the subject to describe the basic, raw, elemental experiences which form complex cognitive experience

He wanted sensations not perceptions, if, in the report, the subject responded with the name of the object rather than the elemental aspects of the stimulus, the subject committed a stimulus error

Titchener He concluded that the elements of consciousness

(the mind) were sensations (elements of perceptions), images (elements of ideas) and affections (elements of emotions)

The elements could be known only by their attributes

Attributes of sensations and images were quality, intensity, duration, clearness, and extensity

Affections could have the attributes of only quality, intensity, and duration

Titchener did not agree with Wundt’s tridimensional theory of emotion, emotions were described in terms of one dimension – pleasantness – unpleasantness

Titchener He described how the elements combine

by using the law of contiguity as many others had done before

What gives sensations and events meaning is the images and events with which the sensation has been associated contiguously in the past

These associations form a core or a context

Thus this description of what gives meaning to sensations is called the context theory of meaning

Titchener The decline of structuralism was

inevitable as people began to question the use of introspection as a viable method in research

Other factors which contributed to the decline were the development of the study of animal behavior, the lack of interest in practical applications on the part of structuralists, and the development of behaviorism and objective methods of research

Franz Brentano 1838 -1917 For Brentano, the important aspect of the

mind was not what was in it but what it did, study should emphasize the mind’s processes

Mental processes are aimed at performing some function thus his view was called act psychology

All mental acts incorporate something outside of itself

Intentionality He employed phenomenological introspection

– introspective analysis of intact, meaningful experiences

Carl Stumpf 1848-1936 Like Brentano, Stumpf argued for study of

intact, meaningful experiences, (phenomenology)

Influenced the development of Gestalt psychology

The three “founders” of Gestalt psychology studied with Stumpf

Stumpf and a student Oskar Phungst helped investigate the Clever Hans phenomenon

Edmund Husserl 1859-1938 For Husserl, there are two types of introspection, one

focuses on the intentionality described by Brentano and the second focuses on subjective experience – the processes a person experiences

This second introspection focuses on the essences of mental processes

He referred to it as pure phenomenology His goal was to create a taxonomy of the mind –

describe the mental essences by which humans experience themselves

The phenomenologies of Brentano, Stumpf, and Husserl all insisted that the proper subject matter of psychology was intact, meaningful psychological experiences

This approach was to impact Gestalt psychology and existentialism

Oswald Kulpe 1862-1915 In contrast to Wundt and Titchener, Kulpe proposed

that some thought could be imageless and also that the higher mental processes could be studied experimentally and set out to do so by using his method called systematic experimental introspection

The imageless thought controversy continued for many years, and highlighted the methodological problems of introspection

The most influential work which came out of the Würzburg school (where Kulpe was the leader) was the idea of mental set

Mental set is a determining tendency, which causes the person to behave in certain ways completely unaware that they are doing so

The mental set can be induced by instruction or by simply the person’s past experiences

Hans Vaihinger 1852-1933 Proposed that societal living requires that we

give meaning to our sensations, and we do that by inventing terms, concepts, and theories and then acting “as if” they were true

In other words, we can’t know whether our sensations correspond to reality, but we act as though they do

This invention of meaning is part of human nature

The ‘useful fiction’

Hermann Ebbinghaus 1850-1909 Researched learning and

memory using a unique methodology

This was important because this was the first time that learning and memory had been studied as they occurred and it illustrated that these processes could be studied objectively

Many of his findings are still cited today and most of the major conclusions reached are still valid today

Ebbinghaus Method He developed nonsense syllables to use as stimuli in

his research These provided series of stimuli that were essentially

meaningless The subject is to learn (memorize) a series of syllables

by looking at them sequentially until mastery Then after various time intervals they were to relearn

the same list The difference in number of exposures to relearn the

list in comparison to the number of exposure to mastery at the initial exposure was called the savings score

Ebbinghaus Among the conclusions were: More rapid forgetting during the first

hours following learning and slower thereafter

Overlearning (continuing to study past mastery) decreased the rate of forgetting

Distributed practice was more effective than massed practice