Wilhelm Wundt (1832-1920) started as lab assistant of Helmholtz; in 1879 established the first psychological research laboratory, at Leipzig. Wundt carried out studies of reaction time, stimulus discrimination, association of stimuli. Obtained time estimates of processes beyond simple perception, including apperception - selective/ conscious attention calling for time to interpret an experience in one's consciousness (hear tone, press button: reaction times are longer if the subject's attention is directed to the tone, than if he is attending to the finger movement directly).
Wundt popularised introspection, in which a highly trained observer observes some simple event - one that could be measured by quality, intensity, or duration - and records his/her(?) responses to variations of those events. Involves systematic analysis one's own mental experience in order to identify its elements. Introspection was later a major target of attack of the behaviourists.
Wundt's forgotten contributions
Top-down approach: Unlike many other psychophysicists, Wundt believed that the experimental study of sensations was limited in scope and depth and that a cultural psychology was necessary, involving study of cultural practices, i.e. the products of the mind: customs and rituals, mythology, literature and art. In the last 20 years of his life he produced a 10-volume work called Völkerpsychologie, which included the idea of stages of cultural development (see sec. ).
Wundt's rich work was misrepresented in USA by his student and translator, Edward B. Titchener who emphasised only introspectionism and that too in simplistic terms omitting methodological details. Some phenomena that were studied in Wundt's labs but noticed in the USA only years later were, apperception (rejected by Titchener) and short-term memory, including the famous limitations on short-term memory to 7 or so ``pieces'' of information. Wundt also studied psycholinguistics and invented the tree diagram of syntax.
Hermann Ebbinghaus (1913) measured skill at memory tasks by using as stimuli pronounceable nonsense syllables like DAX and PAF. Aim was to avoid contamination by earlier experiences and associations. Studied forgetting curve, effects of rehearsal, backward and forward interference, etc.
Ebbinghaus found rules like, ``repetition leads to better retention, more so when spread across several days'' and ``amount retained is a log function of time''. He later continued with S-R models to explain these results. Retention was seen as an indicator of learning.