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.
1 The time interval from first sighting of the iceberg to impact was a little over 30 seconds. 2  The Titanic sank 2 hours and 40 minutes after hitting the iceberg.  It probably took Titanic about 15 minutes to sink to her final resting place on the ocean floor.