The most commonly prescribed antidepressant (and antianxiety) medications out there are the SSRI, selective serotonin reuptake inhibitors. These include drugs like fluoxetine (Prozac), citalopram (Celexa), or sertraline (Zoloft). How these drugs work, however, is still up for debate. At first, everyone thought that, because these drugs increase levels of the neurotransmitter serotonin in the brain, that depression must be caused by low levels of serotonin, and the increase would make you feel better. We have since learned that this is not the case. Headaches don’t result from lack of aspirin, and depression doesn’t result from lack of serotonin. The next theory for how depression, and antidepressants, might work was the neurogenesis theory. We used to believe that you were born with all the neurons you’d ever have, but we now know that neurogenesis, the birth of new neurons, occurs throughout life in areas of the brain like the hippocampus, an area usually associated with learning and memory. Antidepressants can increase neurogenesis, on a time course which matches the clinical efficacy of antidepressants. But now we are starting to think that it might be more complicated than that (via Stress and antidepressants: by their powers combined | The Scicurious Brain, Scientific American Blog Network)
Our story is the story of the universe.
Every piece of everything, of everything you love and everything you hate, of the thing you hold most precious, was assembled by the forces of nature in the first few minutes of the life of the universe, transformed in the hearts of the stars or created in their fiery deaths.
And when you die, those pieces will be returned to the universe in the endless cycle of death and rebirth.
What a wonderful thing it is to be part of that universe. What a story, what a majestic story.
|—||Professor Brian Cox (via fyeahcarlsagan)|
A second-grader asks Neil deGrasse Tyson whether two black holes can collide and swallow one another. The answer involves backwards time travel – enough said.
Europe’s shifting borders – alliances, unions, territories, occupied land – between 1000 AD and 2003, animated.
Also see 200 countries over 200 years animated by the BBC and Hans Rosling.
|—||Ernest Hemingway’s letter to his parents after being severely wounded in Italy during WWI, from this collection of young Hemingway’s letters. (via explore-blog)|
|—||Alfred Hitchcock (via penamerican)|
How the world-famous Harris Tweed, dubbed by its aficionados “the greatest cloth of all,” comes into existence.
Color-mapping the outcome of every American presidential election ever. Also see 88 years of red-blue divide animated in one minute.