While scientific evidence does not support telepathy or any extrasensory perception between twins, a unique type of bond between identical twins called the twin connection exists. Identical twins have a genetic similarity of 100%, leading to similarities in physical traits, genetic predispositions, cognitive abilities, and psychological characteristics.

Some twins describe an unspoken understanding and an intense emotional connection with each other. This special bond may result from pre-natal environmental similarities, shared prenatal experiences, and postnatal influences such as nurturing parents, similar social interactions, and a close shared environment. These experiences shape identical twins, leading to synchronized responses, intuition regarding each other's emotions, thoughts, and behaviors, and mutual knowingness to some extent.