Chapter 4: The Nineteenth-Century Transformation of Psychology

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Chapter 4 The Nineteenth-Century Transformation
of Psychology

• A History of Psychology
• (3rd Edition)
• John G. Benjafield

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Psychology in the Nineteenth Century

• Beginning of nineteenth century
• Many believed psychology could never be a science
• End of nineteenth century
• Possibility that psychology could be a scientific
  discipline seemed more plausible

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J.F. Herbart (17761841)

• Attempted to cast a psychological theory in
  purely mathematical terms
• Interested both in what was above and below the
  threshold of consciousness
• Below the threshold of consciousness
  unconscious events that could become conscious

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J.F. Herbart

• Assumption that all mental life is the result of
  the action and interaction of elementary ideas
• Elementary ideas entirely simple concepts or
  sensations
• Ex. red, sour

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J.F. Herbart

• Some ideas facilitate each other, while other
  ideas inhibit each other
• Process of inhibition can be put into
  mathematical terms
• No matter how much B is inhibited by A, it will
  never be less than zero

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J.F. Herbart

• Apperceptive mass the set of ideas that
  assimilates ideas consistent with it and rejects
  ideas inconsistent with it
• All concepts strive against suppression
• This striving for expression in consciousness is
  the source of the emotions
• Herbarts psychology is dynamic

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Herbart and Educational Psychology

• Goal of education instill the values of the
  established order
• Steps for instruction
• 1. Preparation
• 2. Presentation
• 3. Association
• 4. Generalization
• Fifth step added later Application

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Herbarts Contributions to Psychology

1. Notion that ideas can move back and forth across
   a threshold of consciousness
2. Attempt to apply mathematics to psychology
3. Attempt to apply psychological ideas to education

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G.T. Fechner (18011887)

• Studied medicine at Leipzig, Germany
• Moved to literary field
• Studied physics
• Became professor of physics at University of
  Leipzig
• Responsible for creating an approach to
  psychology that was seen as truly scientific

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Psychophysical Parallelism

• Panpsychism the notion that the mind permeates
  everything in the universe
• Intimate relationship between mental and physical
• Relationship is one of psychophysical
  parallelism a strict parallelism between body
  and soul such that from one, properly understood,
  the other can be constructed

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Psychophysics

• Inner psychophysics the study of the
  relationship between mind and brain
• Outer psychophysics the study of the connection
  between stimulus magnitudes and the intensity of
  the resulting sensations

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Webers Law

• Webers Law the relation between a stimulus
  magnitude and the amount by which that magnitude
  must be changed in order for the subject to
  perceive a Just Noticeable Difference (JND)
• Requires that we regard our basic experiences, or
  sensations, as quantifiable
• Quantity objection a refusal to accept this
  assumption of psychophyics

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Fechners Psychophysical Methods

1. Method of just noticeable differences
2. Method of right and wrong cases
3. Method of average error

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Experimental Aesthetics

• Experimental aesthetics psychology of beauty
• Aesthetics from above evaluate art according to
  standards derived from some theory of what art
  should be
• Aesthetics from below depends on obeservations
  of spectators responses to art in order to try
  to understand the effects that art has on people
• Empirical

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Hermann von Helmholtz (18211884)

• One of the greatest scientists of the 19th
  century
• Career marked by his ability to bring the fields
  of physiology, physics, and mathematics to bear
  on any one subject
• Influenced by Johannes Müller
• Advanced a theory of specific energy of nerves

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Hermann von Helmholtz

• All nerves operate in the same way and transmit
  impulses at the same speed
• Different experiences arise when nerves connect
  different sense organs to different places in the
  brain

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Helmholtz on Perception

• Young-Helmholtz Theory of Colour Perception the
  degree to which each cone in the eye is
  stimulated determines the colour we see
• Red, green, and blue receptors
• Also Trichromatic Theory of Colour Perception
• Place theory nerves located at different places
  in the cochlea are responsible for the perception
  of different pitches

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Unconscious Inference

• Unconscious inference we infer, on the basis of
  previous experience, that particular objects in
  the world have given rise to the images on our
  retinas.
• The result of this process is the
  three-dimensional world we experience

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Ewald Hering (18341918)

• Formulated a competing theory to Helmholtzs
  theory of colour perception
• Opponent process theory of colour vision
• The visual system is based on three pairs of
  antagonistic processes
• Light acts on each pair to yield one of its
  component colours but inhibit the other
• The pairs are yellow-blue, red-green, and
  white-black

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Christine Ladd-Franklin (18471930)

• Trained for a PhD in logic and mathematics at
  Johns Hopkins University
• Not awarded the degree because she was a woman
• Unable to hold a regular university position for
  most of her career because she was married

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Ladd-Franklins Theory of Colour Perception

• Evolutionary-based theory
• Stage 1 vision sensitive only to achromatic
  colours ranging from white to black
• Rods represent the earliest stage of the
  development of vision
• Stage 2 emergence of cones sensitive to yellow
  and blue
• Stage 3 some of the cones sensitive to yellow
  undergo a further specialization to become cones
  sensitive to red and green
• Evidence for her theory comes from the study of
  colour blindess
• Studied people unable to see red and green but
  able to see yellow and blue
• Law of progressions and pathologies the last
  system to evolve is the first to show effects of
  degeneration

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The Localization of Function

• Localization of function controversy controversy
  over the attempts to locate particular
  psychological functions in the cortex of the
  brain
• Phrenology
• Study of brain injuries

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Phrenology

• Franz Joseph Gall (17581828) and J.G. Spurzheim
  (17761832)
• Believed the more highly developed a function,
  the larger it would be
• The larger a function, the more it would protrude
  from the skull
• Thus, one could divine a persons strengths and
  weaknesses by examining the shape of skull
• Phrenological chart chart of the skull
  representing the locations of various
  psychological functions

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The Study of Brain Injuries

• Paul Broca (18241880)
• Investigated the loss of the ability to express
  ideas by means of speech (Brocas aphasia)
• Autopsy of patient showed severe damage to a part
  of the left hemisphere (Brocas area)
• Karl Wenicke (18481905)
• Studied 10 cases of patients who could speak but
  could not understand what was said to them
  (Wernickes aphasia)
• Found lesions in the left hemisphere (Wenickes
  area)

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Study of Brain Injuries

• Studies of the relationship between the loss of
  psychological function and brain damage
• Can be a very suggestive source of evidence
• Are seldom definitive or complete

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Francis Galton (18221911)

• Born in England
• Cousin of Charles Darwin
• One of the most versatile and prolific scholars
  in the history of psychology
• Many of his opinions are still controversial

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Hereditary Genius

• Galton developed the hypothesis that ability and
  genius are hereditary
• Galtons Law the two parents contribute one-half
  of the total heritage of the offspring, the four
  grandparents one-quarter, etc.

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Eugenics

• To Galton, the implication of his studies was
  that society should encourage selective breeding
  of humans
• Eugenics
• Eugenic movement became influential in the early
  twentieth century

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Galton and Statistics

• Normal distribution a symmetrical distribution,
  with an equal number of events on the left as on
  the right
• Regression towards the mean occurs as a
  mathematical necessity whenever two variables are
  not perfectly correlated

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Galton and Memory

• Examined his own memory in great detail
• Employed techniques that have developed into
  widely used experimental procedures
• Autobiographical memories memories of events in
  ones life

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Herbert Spencer (18201903)

• 1852 coined the phrase survival of the fittest
• Evolutionary theory applied to the inorganic,
  organic, and super-organic (ie. societies)
• Law of evolution evolution is a process by which
  a system moves from an indefinite, incoherent
  homogeneity, to a definite coherent heterogeneity

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Social Darwinism

• Social Darwinism individuals should be left to
  their own devices
• (Ex. the state should not interfere with the
  evolutionary process)
• Some successful American business people took up
  social Darwinism
• Ex. John D. Rockefeller, Andrew Carnegie