LENGTH OF FINGER PREDICTS SCORE

Mea­sure­ments of chil­dren’s fin­ger lengths ap­pear to pre­dict their scores on math and lit­er­a­cy tests, re­search­ers have found.

The study might raise anew the con­tro­ver­sial is­sue of wheth­er boys and girls have dif­fer­ent in­nate abil­i­ties, sci­en­tists said. This is be­cause fin­ger length is pro­posed to be re­lat­ed to dif­fer­ences in hor­mones re­spon­si­ble for de­ve­lop­ment­al dif­fer­ences in boys and girls.In a study to ap­pear in the Brit­ish Jour­nal of Psy­chol­o­gy, re­search­ers com­pared the fin­ger lengths of 75 seven-year-old chil­dren with stand­ard­ized test scores. They found what they called a clear link be­tween math and lit­er­a­cy per­for­mance and the rel­a­tive lengths of their in­dex and ring fin­gers.

The researchers said the link is thought to stem from dif­fer­ent lev­els of the hor­mones tes­tos­ter­one and oes­tro­gen in the womb. Tes­tos­ter­one is be­lieved to pro­mote de­vel­op­ment of brain ar­eas “often as­so­ci­at­ed with spa­tial and math­e­mat­i­cal skills,” while oes­tro­gen may do the same for ver­bal abil­ity, said study lead­er Mark Bros­nan, head of the Un­ivers­ity of Bath, U.K. psy­chol­o­gy de­part­ment.

“In­ter­est­ingly, these hor­mones are al­so thought have a say in the rel­a­tive lengths of our in­dex and ring fin­gers. We can use mea­sure­ments of these fin­gers as a way of gaug­ing the rel­a­tive ex­po­sure to these two hor­mones in the wom­b.” Tes­tos­ter­one and oes­tro­gen are al­so re­spon­si­ble for the de­vel­op­ment of male and female sex­u­al char­ac­ter­is­tics, re­spec­tive­ly.The re­search­ers meas­ured chil­dren’s fin­gers and di­vid­ed the length of the in­dex fin­ger by that of the ring fin­ger. The in­ves­ti­ga­tors found that a smaller ra­tio—that is, a long­er ring fin­ger with res­pect to index finger—was linked to bet­ter scores in math com­pared to lit­er­a­cy. This fin­ger con­fi­gur­ation also sig­nals great­er pre­na­tal tes­tos­ter­one ex­po­sure, they said.

Sci­en­tists asked to com­ment on the finger-length study last week did­n’t dis­pute that it might pro­vide ev­i­dence bear­ing on the de­bate. But they urged cau­tion in in­ter­pret­ing the find­ings. Some not­ed that finger-length is on­ly an in­di­rect in­dic­a­tor of pre­na­tal hor­mone ex­po­sure. Finger ratio is just a “proxy” for hor­mone ex­po­sure, which can also be meas­ured di­rect­ly in the am­ni­ot­ic flu­id where the fe­tus floats, noted Si­mon Baron-Cohen of Ox­ford Uni­ver­si­ty, U.K., who has ex­ten­sive­ly stud­ied ma­le-female brain dif­fer­ences