The D2:D4 digital index is used as a biological indicator for Specific Language Disorders

I+DEL group has just published a new article along with the Biological department from the University of the Balearic Islands. In this last study, Eva Aguilar-Mediavila with Antonia Font-Jordà, Antoni Gamundí, and Maria Cristina Nicolau Llobera have found evidence about the positive use of the D2:D4 digital index as a biological indicator for the SLI.

What is the D2:D4 digital index?
This digital index is considered a direct indicator of the testosterone’s prenatal exposition. Previous studies have linked linguistic competence with aggressive behavior which has led to consider it as a potential biological marker.

In this mentioned research, we have studied 33 subjects with an average age of 6, all bilingual speakers in Catalan and Spanish and living in Mallorca. We have compared the result of the D2:D4 digital index between children with SLI and other children with a typical language development. Using this method, we have established the correlation among social, cognitive and linguistic behavior.

The study results have shown that a low testosterone exposition during pregnancy, being this a D2:D4 higher index, can be related to a higher probability to suffer from SLI in male children. Nevertheless, this index has not shown a correlation among other social behaviors that are explained by the subject’s linguistic and cognitive level. These children linguistic behavior is related to the testosterone’s prenatal exposition, but the worse adaptive abilities, (e.g: social abilities, leadership…), and the internal behaviors, (e.g: depression, anxiety…), were the consequence of their linguistic and cognitive difficulties.

If you are interested in reading this study at a deeper level, you can do it here.