I heard myself say, “I can’t think about that right now.” There were what felt like a million things vying for my attention and when my mother asked what time I would be there for dinner I simply didn’t have the bandwidth to come up with an answer. So I told her I would get back to her the next day.

If you’ve experienced something similar, then let me reassure you. There’s nothing wrong with us—it’s simply an effect of how our brain works under stress.

Stress levels ar...