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scientific psychology: *
Before the Austrian Sigmund Freud (1856–1939) put psychology on the map, German psychology as Experimental Psychology emerged in the 19th century. A pioneer was Ernst Heinrich Weber (1795-1878), a founder of experimental psychology. His main interests were the sense of touch & kinesthesis; his main contribution was the suggestion that judgments of sensory differences are relative & not absolute. This is expressed in "Weber's Law," in which the just-noticeable difference is a constant proportion of the on-going stimulus level. This was stated as an equation & proved sensory events can be related mathematically to measurable relative changes in physical stimulus values:
ΔR/R = k
ΔR: amount of stimulation that needs to be added to produce a jnd (just-noticeable difference)
R: amount of existing stimulation
K: constant (different for each sense)
(as labelled by Gustav Theodor Fechner)
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The man responsible for the above equation was Gustav Fechner (1801-1887). He published in 1860 the first work of experimental psychology, "Elemente der Psychophysik." He realized the importance of Weber's research; he was interested in establishing a scientific study of the mind-body relationship (psychophysics). Much of his research focused on the measurement of psychophysical thresholds & just-noticeable differences, and he invented the psychophysical method of limits, the method of constant stimuli, and the method of adjustment. He translated Weber’s law into an equation & proved sensory events can be related mathematically to measurable relative changes in physical stimulus values. The complete equation (known as Fechner's law) is given below:
Wilhelm Wundt (1832–1920), another "father of experimental psychology” introduced a mathematical & experimental approach & founded the first psychology lab in Germany. Other experimental psychologists of this era included Hermann Ebbinghaus & Edward Titchener. Ebbinghaus (1850-1909), a pioneer in experimental study of memory, known for his discovery of the forgetting curve & the spacing effect as well as the learning curve. The forgetting curve hypothesizes the decline of memory retention in time. His equation for the decline of memory is given below along with the graph it produces.
Titchener (1867-1927 ) was an English psychologist, who studied in Leipzig with Wundt in 1890. Along with Wundt, he is credited with the theory of structuralism, the first "school" of psychology.
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Oswald Külpe (1862 -1915) was the main founder of the Würzburg School in Germany, a pupil of Wundt for 12 years. However unlike Wundt, he believed experiments were possible to test higher mental processes. In 1883 he wrote Grundriss der Psychologie, which had strictly scientific facts and no mention of thought. His Würzburg School was a milestone in the development of experimental psychology & provided an alternative to the structuralism of Titchener & Wundt. It focused mainly on mental operations such as mental set & imageless thought.