Government Internet Shutdown Mobilized the Masses

The government could have been smarter. The best way to divert our youth from politics would have been to give them free, unlimited internet access a few days before the protests, and drop the price of beer and condoms – all the while playing “Be safe, live long” songs on the radios. The youngies would have been watching porn, WhatsApping and YouTubing, and would have been too distracted to think about politics. Shutting down the internet achieved the opposite. Far from limiting youth ...

 Did Lower Testosterone Help Civilize Humanity?

A new study appearing Aug. 1 in the journal Current Anthropology finds that human skulls changed in ways that indicate a lowering of testosterone levels at around the same time that culture was blossoming. “The modern human behaviors of technological innovation, making art and rapid cultural exchange probably came at the same time that we developed a more cooperative temperament,” said lead author Robert Cieri, a biology graduate student at the University of Utah who began this work as a...

 Temperament is Influenced by Chemicals

Some 40 percent to 60 percent of the observed variance in personality is due to traits of temperament. They are heritable, relatively stable across the life course, and linked to specific gene pathways and/or hormone or neurotransmitter systems. Moreover, our temperament traits congregate in constellations, each aggregation associated with one of four broad, interrelated yet distinct brain systems: those associated with dopamine, serotonin, testosterone, and estrogen/oxytocin. Each constellat...

 Testosterone's Effect on Memory

Like many other areas of development, memory generally matures more rapidly in girls than boys. Beginning in the womb, female fetuses are known to habituate to auditory stimuli about two weeks earlier than males. After birth, they are more advanced at visual habituation. Toward the end of the first year, girls are about a month ahead in tests of short-term, explicit memory, like remembering, after a few seconds' distraction, where they just saw a toy being hidden. Girls also outperform boys o...

 Genes versus Hormones in Homosexuality

It is clear, however, that the cause of homosexuality lies in some unusual balance of hormonal influence in the womb but not later on, a fact that further supports the idea that the mentality of sexual preference is affected by prenatal sex hormones. This is not incompatible with the growing evidence that homosexuality is genetically determined. The "gay gene" that I will discuss in the ext chapter is widely expected to turn out to be a series of genes that affect the sensitivity of certain t...

 How Testosterone Affects the Brain

We last met the steroid hormone testosterone in fish and birds where it was rendering them more vulnerable to parasites by exaggerating their sexual ornaments. In recent years more and more evidence has been found that testosterone affects not just ornaments and bodies but also brains. Testosterone is an ancient chemical. found in much the same form throughout the vertebrates. Its concentration determines aggressiveness so exactly that in birds with reversed sex roles, such as phalaropes and ...