Seeing or hearing someone yawn can make you yawn. This phenomenon is not limited to humans; some animals experience contagious yawning, too. But why is yawning contagious? Brain cells called ...

Find yourself yawning a lot? Do you need that third or ... “When we do actual tests to measure how well your brain is functioning — reaction time, the ability to recall, memory tests ...

Find yourself yawning a lot? Do you need that third or fourth cup of ... “When we do actual tests to measure how well your brain is functioning — reaction time, the ability to recall, memory tests, ...