The Scientific Reason You Forget the Most Random of Things

Updated: Oct. 07, 2022

If you've ever drawn a blank—like your neighbor's name, your grandmother's hometown, or that actress from your favorite movie—then you're in good company. It happens to all of us. Here's what's really going on.

What’s it called again—you know, that thing when you can’t remember a simple fact that you know you know? It’s right there on the tip of your tongue! Oh, that’s right: Brain freeze. Brain cramp. Mental block. Tip-of-The-Tongue Syndrome. Drawing a blank. Whatever you happen to call it, it’s happened to most people at some point—an unexpected, unsolicited, and highly uncomfortable lapse in memory.

Why we draw a blank

“On a daily basis, we so much spend a lot of time functioning on auto-pilot, carrying out routine activities without much conscious effort or awareness, that it’s amazing we’re able remember anything at all,” says Jodi J. De Luca, PhD, a clinical psychologist in Erie, Colorado. Cognitive factors that work against us when we find ourselves struggling to retrieve some seemingly simple and innocuous piece of information include:

  • Blocking: When we’re called upon to retrieve a piece of information, competing memories of a similar nature may come bubbling to the surface. One may mute out the other temporarily. For example, as our brains consciously go to retrieve the name of an Adam Sandler movie, we’re suddenly reminded of a number of Judd Apatow movies, and our minds draw a blank.
  • Interference: Founded by German psychologist, John Bergstrom in 1892, the “theory of interference” holds that new information can interfere with the brain’s ability to retrieve old information. For example, we might call a current partner by a former partner’s name. Or vice versa.

The-Scientific-Reason-You-Can't-Remember-Simple-Info-When-You-Need-ItWAYHOME studio/shutterstock

Sometimes, it’s more than just a cognitive glitch, however. “When we are under any kind of stress, whether physical, psychological, or emotional, the parts of the brain that are important to survival are heightened, while those less critical to survival are overpowered,” says Courtney Rodriguez, LMHC, NCC. It doesn’t matter that the stress is not a response to a life or death situation. Stress of any kind puts our bodies into fight or flight mode, during which information that isn’t critical to our immediate survival becomes less accessible. Specifically, explains Eve Del Monte, a licensed professional counselor in Baltimore, Maryland, stress causes the release of the hormone, cortisol, which inhibits certain brain functions in the interest of “survival,” regardless of whether the actual stressor is a matter of life or death. One of those brain functions is our ability to access language readily.

Stressors can include those in the immediate circumstances (for example, speaking to a new colleague). But stressors can also be of a more chronic nature, says Dr. De Luca. These include:

  • Brain Injury
  • Chronic Stress
  • Depression
  • Anxiety disorder
  • Distractibility (Poor Attention & Concentration)
  • Unhealthy Diet
  • Chaotic Environment
  • Grief
  • Health Issues
  • Lack of Exercise
  • Lack of Mental Stimulation
  • Lack of Sleep
  • Lack of Social Support
  • Medications
  • Certain vitamin deficiencies, including B-12 and D.

Why we suddenly remember—later

After experiencing a mental block, it’s not uncommon to suddenly and seemingly inexplicably, find our brains serving up whatever it was we’d forgotten. Unfortunately, this tends to happen long after it matters. “We’re humans, but even computers freeze up,” points out Paul DePompo, Psy.D., ABPP, a certified cognitive-behavioral therapist in Southern California. “Like a computer, sometimes we just need to reboot. For humans, that means taking a mental break. The information is there; it’s just a matter of accessing it.”

Dr. De Luca refers to these little, out-of-the-blue resurgences of memory as mind pops and sometimes that they’re not entirely random, but rather a function of the way our brains respond to cues in the environment. “Our memories are hard-wired,” she says, and that includes even memories of having had a mental block or a brain cramp hours earlier. Something in the current moment triggers the memory of the incident and also brings forth whatever it is that we were trying to remember when we had the lapse.

What we can do about it

Obviously, eliminating diagnosable factors is a start. If you’re experiencing an illness, treat the illness. If your diet is lacking, improve your diet. “Anything that reduces stress can help improve recall,” points out Dr. De Luca, including exercise, limiting multitasking, and maintaining healthy relationships. When you find yourself in the midst of a brain block, take a few deep breaths, suggests Del Monte. If you know you’re going to be in a stressful situation, visualize it in advance, suggests Rodriguez.

Don’t be hard on yourself about it, Dr. DePompo adds, because that only increases stress and makes the moment feel worse. And remember that “forgetting is a natural process of memory. By forgetting, we make a conscious effort remember, engaging in the process of memory retrieval,” as Dr. De Luca says. “In short, forgetting, although frustrating, activates the brains memory process.” For extra help, however, try these tips for maintaining a healthy brain as you age.