Incredible bond: Conjoined twins Krista and Tatiana Hogan are joined at the skull, but they may also share one mind thanks to a unique neural link which effectively allows them to see with each others' eyes Like any twins, the Hogans have their differences - for a start, four-year-old Krista loves tomato ketchup, but her sister Tatiana hates it.
Except their mother only knows that because one day when Krista was happily eating the sauce, Tatiana made a face and tried to scrape it off her tongue - even though she hadn't touched a drop.
It's just one of the remarkable incidents which have astonished doctors in British Columbia treating the conjoined twins, who say they may have a unique neural link which means they share one mind.
Astonishing: Krista, right, can correctly name the soft toy her mother shows to her twin sister Tatiana - even though she cannot see it. They have quite different personalities, and Krista is the bossier of the twoThey believe the sisters share a part of the brain called the thalamus, which sends physical sensations and motor functions to the cerebral cortex.
In other words, they are effectively able to see through each other's eyes - and perhaps even hear each others' thoughts.
In an in-depth interview with the New York Times their mother, Felicia Simms, revealed how when one twin has her eyes covered, she can identify what the other one sees - and they even respond with a 'whoa' as if they are full when the other one drinks too much juice.
Unique girls: When one of the girls drinks, the other one will put a hand on her own stomach - despite not touching a drop. Each one can also seemingly taste something the other is eating
Shared mind? The girls are believed to have a unique thalamic bridge, in which they share the part of the brain which controls sensory perception source: dailymail