Alan David Baddeley CBE FRS (born 23 March 1934) is a British psychologist. He is known for his research on memory and for developing the three-component model of working memory. He is a professor of psychology at the University of York.

Baddeley was born in Leeds, Yorkshire on 23 March 1934.^[1] He lived there with his parents, Donald and Nellie Baddeley, until leaving for university.^[2] He decided to study psychology and was originally interested in psychoanalysis. Later he changed his focus to evidence-based psychology.^[3] In 1956, Baddeley went to the United States of America to continue his studies. After spending a year in America, he returned home. He then went to Cambridge, where he met and married Hilary Ann White. Baddeley and his wife have three sons.^[2]

Baddeley has taught and conducted research at University of Sussex, University of Stirling, MRC Applied Psychology Unit, Churchill College, University of Cambridge, and University of Bristol. He is currently a professor of psychology at the University of York.^[4]

Baddeley attended the University College London from 1953 to 1956. He then obtained an MA from Princeton University's Department of Psychology in 1957. He earned a PhD from University of Cambridge in 1962.^[5] He has been awarded Honorary Doctorates by University of Essex in 1999,^[6] Plymouth University in 2000,^[7] and University of Bristol in 2019.^[8]

In 1974, working with Graham Hitch, Baddeley developed an influential model of working memory called Baddeley's model of working memory,^[9] which argues for the existence of multiple short-term memory stores and a separate interacting system for manipulating the content of these stores. There are three components of this model: the phonological loop, the central executive, and the visuospatial sketch pad.^[9] In 2000, Baddeley suggested adding a fourth component to his memory model called the episodic buffer.^[10] The model accounts for much of the empirical data on short-term retention and manipulation of information.

His landmark study in 1975 on the capacity of short-term memory^[11] showed that people remembered more short words than long words in a recall test. This was called the word length effect and it demonstrated that pronunciation time rather than number of items determines the capacity of verbal short-term memory. This study also found that when participants repeated an irrelevant sound while reading the words, the word length effect does not happen.^[11]

Working with Barbara Wilson, Baddeley also did several important studies on amnesia and memory.^[12][13] They studied patients with temporal lobe damage that caused memory problems. Results of such studies provide evidence that short-term and long-term memory are not one system. The amnesia patients had normal short-term memory but impaired long-term memory.^[14]

Baddeley has also done research studies using divers and various underwater conditions. He studied the effects of depth and pressure on dexterity,^[15] the impact of temperature on response time,^[16] and context-dependent memory on land and underwater.^[17]

Baddeley was the director of the Cognition and Brain Sciences Unit, a branch of the UK Medical Research Council, based in Cambridge, from 1974 - 1997.^[18] He was elected a Fellow of the Royal Society in 1993^[19] and in 1996, was elected a Foreign Honorary Member of the American Academy of Arts and Sciences.^[20] In 2001, Baddeley received the American Psychological Association (APA) Award for Distinguished Scientific Contributions.^[21] Baddeley was given the Lifetime Achievement Award by the British Psychological Society in 2012.^[22] He also received the Major Advancement in Psychological Science Prize from the International Union of Psychological Science in 2016.^[23]