In the film “Bedtime for Bonzo,” when college professor Peter Boyd (Ronald Reagan) attempts to demonstrate that he can teach a chimpanzee (Bonzo) right from wrong, the chimp seems to enjoy the instruction.

One important lesson he's taught: When it's time to hit the hay, that means lights out.

Can humans today learn the lesson professor Boyd was trying to teach Bonzo back in in 1951 — that getting to bed on time, with no TV or screen time, is essential for good brain health?

Unfortunately, many people are late-night viewers. A University of Pennsylvania study found that late-night TV (11:30 p.m. to 2 a.m.) is a major reason why up to 40 percent of U.S. adults don't get the recommended seven to eight hours of sleep nightly.

And lack of sleep takes a toll on your brain. A recent study in Nature Scientific Reports reveals that adults 50 and older who, over a six-year stretch, watched more than 3.5 hours of TV daily experienced a greater cognitive decline than adults who watched 2.5 hours a day or less.

That affects a lot of people, as according to a 2016 Nielsen report, American adults watch an average of five hours and four minutes of television per day

Now, there's nothing wrong with watching “The Dr. Oz Show” (recorded or otherwise) and learning how to feel younger. But no TV in the bedroom.

In addition, keep your overall tube time to less than 2.5 hours per day.

Don't let it keep you up at night, and you'll remember better what you watched.