The eminent neurologist, neuropathologist and psychologist Pál Ranschburg (1870-1945) made an outstanding impact on the development of the science of Special Needs Education.
 

In 2019, the Library of the ELTE Bárczi Gusztáv Faculty organised an exhibition about the comprehensive scientific works of Professor Ranschburg, based on items preserved in the Special Collection.
 

The exhibition presented Ranschburg’s psychophysiological experiments and self-developed instruments.
 

Perhaps the best known among these is the so-called ’mnemometer’, with its ’stimuli discs’, that Ranschburg used for his study of memory, by which he defined the principle of homogeneous inhibition, known worldwide as the Ranschburg-phenomenon.