Note: As Mike Yassa, the lead author on the study, pointed out to me, the study did not actually test whether consuming caffeine before a task enhances memory, the problem being that other confounding factors can then lead to difference in performances on the test.
The US debt is more than $20.1 trillion, the largest in the world. Here are the 3 reasons it grew so large, and how it damages U.S. economic growth. The US debt is more than $20.1 trillion, the largest in the world.
US debt tops $16 trillion: So who do we owe most of that money to? The Treasury Department reported Tuesday that the national debt had topped $16 trillion, adding fuel to Republicans' criticisms of President Obama's deficit spending just as the Democrats are kicking off their national convention.