By comparing your index and ring fingers, a neuroscientist can tell if you are likely to be anxious or whether you are likely to be a good athlete.
If your index finger is longer than your ring finger, you are likely to be bad at sports but better at verbal memory tasks, a new study says.
But men and women with shorter index fingers compared to their ring finger are less anxious, better at mentally demanding 3D-rotation tasks and better at sport.
Scientists have long known adults whose index finger, the digit next to the thumb, is shorter than their ring finger, the digit next to the little finger, are exposed to greater amounts of testosterone when they were in the womb.
The ratio between the ring and index fingers, known in scientists’ jargon as 2D and 4D, can reveal the levels of testosterone someone was exposed to in the womb.
The greater level of testosterone, shown by the ring finger being longer than the index, means someone is likely to be a better athlete.
'High levels of testosterone generally correlate with superior abilities on tasks that men usually perform better, such as various spatial tasks like directional sense,' Dr Pintzka, one of the researchers, said.
People with more testosterone are better at rotating a complicated object in their head.
The amount of testosterone in the womb has been linked with an increase in certain disorders.
Studies show high levels of testosterone in the womb correlate with an increased risk of developing diseases that are more common in men, such as ADHD, Tourette's and autism.
Low levels of testosterone are associated with an increased risk of developing diseases that are more common in women, like anxiety and depression.
But low levels of testosterone are associated with better abilities in verbal memory tasks, like remembering lists of words.
But, those who do not fall into either of these categories, with index and ring fingers the same length, are more likely to be faithful, according to a study last year.
In contrast, those with a longer ring finger could be more likely to cheat.
The experimental psychologists from Oxford University and Northumbria University studied 600 men and women in Britain and the US, looking at the link between hand shape and sexual habits.