It may be that loneliness may affect systems in the brain dealing with cognition and memory, making lonely people more vulnerable to effects of age-related decline in neural pathways, he suggested.

BBC: NEWS | Health | Loneliness link with Alzheimer's

In this context, he attaches particular importance to Senator Pinochet's memory deficit for recent events, which would affect his ability to relate and understand items of information given to him at a trial, and to his limited ability to comprehend complex sentences and questions and to process verbal information.

BBC: Straw's statement in full

Lead researcher Ilana Hairston said as well as proving sleep deprivation affected spatial memory, the suggestion was that sleep did not affect senses.

BBC: Spatial memory works in a similar way in rats and humans