Twins interact with each other in the womb
In 2011, researchers at Umberto Castiello of the University of Padova in Italy studied 3D videos of twins in their mother ' s womb. At 14 weeks of gestation, twins were seen reaching for each other. By 18 weeks, they touched each other more often than they touched their own bodies. The researchers said that kinematic analyses of the recordings revealed that the twins made distinct gestures toward each other and were as gentle to the other twin ' s delicate eye area as they were when they touched their own.
Some conjoined twins can feel and taste what the other one does
Susan Dominus wrote a piece for The New York Times about two conjoined twins, Krista and Tatiana Hogan, who are attached at the head through a " thalamic bridge," part of the brain that acts as a sort of " neural switchboard " and �lters most sensory input. Scientists have hypothesized that this connection could result in one Hogan sister being able to taste and feel what the other twin is experiencing and to understand each other ' s thoughts. Dominus, who spent a considerable amount of time with the twins for her story, recorded these amazing observations:
“[ Their parents noticed ] when one girl ' s vision was angled away from the television, she was laughing at the images �ashing in front of her sister ' s eyes. The sensory exchange, [ researchers ] believe, extends to the girls ' taste buds: Krista likes ketchup, and Tatiana does not, something the family discovered when Tatiana tried to scrape the condiment off her own tongue, even when she was not eating it."
Forty percent of twins invent their own languages
These twin babies are speaking their own special“ language."
These languages are called autonomous languages. Researchers suspect that twin babies use each other as models in developing language when an adult model language is frequently absent. The " language " consists of inverted words and onomatopoeic expressions. These autonomous languages are formed when two very close babies are learning how to speak a real language alongside one another and naturally often play and communicate with each other. While this is more common among twins, since they are more likely to be around each other and developing at the same rate, this phenomenon can also sporadically occur between two babies who are not twins. The made up " languages " often disappear soon after childhood, once the children have learned a real language.