Two different pathophysiological mechanisms to explain the phenomenology of the visual hallucinations as a result of a wide variety of conditions have been proposed. Visual hallucinations in the context of visual sensory deprivation, migraine and epilepsy seem to be caused by direct excitation of the visual cortex or by de-afferentiation.
Roughly 2 hours and 42 minutes: Titanic struck the iceberg at 11:40pm on the 14th April and sank at 2:20am the next day. When the Titanic hit the iceberg the bottom four floors started flooding and it kept on going until the whole ship split in half and sunk to the bottom of the sea where it split once more into three pieces when it hit the bottom.
The Carpathia was the closest ship to the sinking Titanic, but it was still 4 hours away. It took the Titanic over two hours to fully sink into the ocean and the final part of the ship went under at 2:20am on the morning of April 15, 1912. The Carpathia vessel ended up arriving two hours after the Titanic had already sunk.