In the early 1990s, physicians at the Strasbourg University Hospital in France reported the strange case of a 51-year-old man who experienced unusual epileptic seizures. More than a third of the seizures, it seemed, occurred when he lied for business reasons.
The physicians soon determined the cause of the seizures – a tumour pushing against his amygdala, the brain region that regulates emotions such as fear. Researchers think that the fear he experienced when lying, rather than the lie itself, set off the seizures. Presumably, then, similar emotions felt for other reasons would also set off the same electrical cascade in his brain, says Rebecca Wilcoxson, a forensic psychologist at Central Queensland University in Australia.