Monkeys in Quantum Entanglement? - Mirror-Touch Synesthesia is a medical condition where someone experiences a similar sensation in the same part of the body that another person actually feels. For example, if someone with mirror-touch synesthesia is to observe someone scratching their arm, they would feel the same sensation on their own arm, without carrying out that action. This medical condition was observed in an experiment with monkeys, where a neuron in the brain was activated both when a monkey reaches out to grab something, and when a monkey is observing another monkey doing that same action. One might say that these two monkeys are quantumly entangled by a brain neuron monster.