A study conducted by researchers at Weill Cornell Medical College in New York revealed that some coma patients may have awareness of their surroundings. One in five people were likely "locked in," unable to move any muscles in their body but fully aware of their surroundings and activities. Nicholas Schiff and his team of researchers recorded responses from 353 patients who had suffered from severe brain damage for over eight years. They conducted behavioral and brain imaging tests, asking patients to imagine complex activities such as swimming or walking, with breaks every 15 to 30 seconds. Brain activity in 25% of the patients resembled that of a healthy individual, while 20% of those tested were observed to be in a coma. "These are very demanding tasks – try thinking about swimming on and off for 5 minutes. We don’t know exactly what they are experiencing, but the fact that they can do this means there’s a very good chance that they have awareness," explained Schiff. Out of the 300,000 to 400,000 patients diagnosed with a consciousness disorder worldwide, 100,000 were found to have hidden awareness.