Mental speed – the speed at which we can deal with issues requiring rapid decision-making – does not change substantially over decades. Psychologists at Heidelberg University have come to this conclusion. Under the leadership of Dr Mischa von Krause and Dr Stefan Radev, they evaluated data from a large-scale online experiment with over a million participants. The findings of the new study suggest that the speed of cognitive information processing remains largely stable between the ages of 20 and 60, and only deteriorates at higher ages. The Heidelberg researchers have hereby called into question the assumption to date that mental speed starts to decline already in early adulthood.

“The common assumption is that the older we get, the more slowly we react to external stimuli. If that were so, mental speed would be fastest at the age of about twenty and would then decline with increasing age,” says Dr von Krause, a researcher in the Quantitative Research Methods department headed by Prof. Dr Andreas Voß at Heidelberg University’s Institute of Psychology. In order to verify this theory, the researchers re-evaluated data from a large-scale American study on implicit biases. In the online experiment with over a million participants, subjects had to press a button to sort pictures of people into the categories “white” or “black” and words into the categories “good” or “bad”. According to Dr von Krause, the content focus was of minor importance in the Heidelberg study. Instead, the researchers used the large batch of data as an example of a response-time task to measure the duration of cognitive decisions.