A Powerful Idea About Our Brains Stormed Pop Culture and Captured Minds. It's Mostly Bunk.

When Leonardo DiCaprio's relationship with model/actress Camila Morrone ended three months after she celebrated her 25th birthday, the lifestyle site YourTango turned to neuroscience. DiCaprio has a well-documented history of dating women under 25. "Given that DiCaprio's cut-off point is exactly around the time that neuroscientists say our brains are finished developing, there is certainly a case to be made that a desire to date younger partners comes from a desire to have control," the article said. It quotes a couples therapist, who says that at 25, people's "brains are fully formed and that presents a more elevated and conscious level of connection"--the type of connection, YourTango suggests, that DiCaprio wants to avoid. YourTango was parroting a factoid that's gained a chokehold over pop science in the past decade: that 25 marks the age at which our brains become "fully developed" or "mature." This assertion has been used as an explanation for a vast range of phenomena.