Ranschburg Effect

The Ranschburg effect is the impaired recall of items that repeat within a short list or sequence a person is trying to remember, first described by the Hungarian psychiatrist Paul Ranschburg in 1901 and 1902 under the name homogenous inhibition. The effect is thought to arise because a person recalling a list unconsciously avoids repeating an answer already given, treating repetition as a sign of error, which suppresses correct recall of items that genuinely do repeat; this makes it distinct from the related phenomenon of repetition blindness, in which a person fails to consciously notice a repeated item presented in rapid succession in the first place. Research has found the effect is stronger in older adults than in younger people, and that its strength depends on how far apart the repeated items sit in the sequence, with items repeated close together recalled better than those separated by a greater distance.