Gunnar Johansson was a Swedish

Sweden

Sweden , officially the Kingdom of Sweden , is a Nordic country on the Scandinavian Peninsula in Northern Europe. Sweden borders with Norway and Finland and is connected to Denmark by a bridge-tunnel across the Öresund....

 psychophysicist

Psychophysics

Psychophysics quantitatively investigates the relationship between physical stimuli and the sensations and perceptions they effect. Psychophysics has been described as "the scientific study of the relation between stimulus and sensation" or, more completely, as "the analysis of perceptual...

. He was interested in motion perception in vision. He is most well known for his investigations of biological motion

Biological motion

Biological motion is a term used by social and cognitive neuroscientists to refer to the unique visual phenomenon of a moving, animate object. Often, the stimuli used in biological motion experiments are just a few moving dots that reflect the motion of some key joints of the moving organism...

. He helped develop the rigidity assumption which posits that proximal stimuli that can be perceived as rigid objects are generally perceived as such. Johansson received his Ph.D. from the Stockholm University College in 1950, on the thesis Configurations in event perception. He was professor of psychology at Uppsala University

Uppsala University

Uppsala University is a research university in Uppsala, Sweden, and is the oldest university in Scandinavia, founded in 1477. It consistently ranks among the best universities in Northern Europe in international rankings and is generally considered one of the most prestigious institutions of...

 from 1957 to 1977. In 1970, he was elected a member of the Royal Swedish Academy of Engineering Sciences

Royal Swedish Academy of Engineering Sciences

The Royal Swedish Academy of Engineering Sciences or Kungl. Ingenjörsvetenskapsakademien , founded in 1919 by King Gustaf V, is one of the Royal Academies in Sweden...

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