Sleeping sickness is spread by a parasite that infects the central nervous system and,if left untreated, moves to the spinal column and brain, resulting in mental confusion and eventual death.

VOA: standard.2010.04.05

"When we plotted the circuits in the brain against their childhood lead blood lead levels, we found that those with a higher blood lead measurement had less activity in the part of the brain normally left to do the attention tasks,"

VOA: standard.2009.12.19