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I get asked a lot about how much truth there is in what people say when they talk in their sleep. Sleep talking is very common, occurring in about half of all children and 1 in 20 adults. This is certainly a recurring theme in literature and film. There are also plenty of anecdotal stories about people unwittingly speaking their most deeply help secrets while sleeping, including their latent homosexuality, secret adulterous affairs, and criminal activity.
However, that is all that these are: anecdotal stories, and it would be incorrect to ascribe too much to what is mumbled or cried out by a sleeping person, and very risky to draw conclusions from it.
Incidentally, this is also the view of the courts. In 2001, the conviction of a Massachusetts man convicted of indecent assault and battery of a minor was overturned by the Supreme Judicial Court of Massachusetts after the judges decided that the jury was unfairly prejudiced after hearing what one of the children he was alleged to have abused had said while sleeping.
People looking for more information about sleep talking can find it in Arthur Arkin’s book Sleep-Talking: Psychology and Psychophysiology.
