When Senator Mitch McConnell at one point in 2023 appeared to “blank out” or “freeze” in the midst of delivering remarks in Washington, and was unable to speak or move for about 30 seconds, it caused momentary alarm. He fairly quickly recovered, and the episode was generally regarded as an odd blip of little consequence, perhaps due to the senator just being fatigued.

Medical experts, however, say moments like McConnell experienced are not something to be brushed off as insignificant, even though such episodes can be very short-lived and the person seems back to normal fairly quickly. These freezes are referred to as events of altered mental status. They are neurological phenomena that in most cases call for a mental status exam. Some experts questioned why McConnell wasn’t taken to a hospital for evaluation to assess his overall cognitive and behavioral state.

The reason for advising greater caution and evaluation around a “freezing” episode is the fact that a serious cause might have precipitated it. These causes can include:

Brain Injury Can Lead to Temporary or Permanent Disability

A few months before McConnell’s freeze, he had suffered a severe fall causing broken ribs and a concussion. Brain injury can lead to temporary or permanent disability. Chronic degenerating brain diseases (e.g., Parkinson’s, amyotrophic lateral sclerosis [Lou Gehrig’s disease], or Alzheimer’s) can be associated with freezing. Even if the freezing itself goes away, the underlying disease may still be present.

Transient Ischemic Attack (TIA)

Sometimes termed a ministroke, symptoms of a TIA can be a brief seizure or freezing. Mimicking stroke, TIA symptoms typically include weakness or numbness on one side of the body, loss of vision, loss of speaking ability, or dizziness. It can be caused by a blood clot forming inside an artery, impeding blood flow to the brain. According to Harvard Health Publishing (HHP), a TIA may last anywhere from 30 seconds to 20 minutes, with most lasting at least five minutes. HHP adds that recognizing a TIA is important because nearly one in five people who have a suspected TIA will suffer a full-blown stroke within three months. A person who had a TIA may or may not be aware of it while it was happening. It was reported that McConnell could not recall what happened to him or how long his episode lasted. A stroke neurologist at Massachusetts General Hospital observed: “Because TIAs don’t last long and don’t always have a lasting effect, it’s easy for people to shrug them off.  But a TIA is your body warning that you’re at high risk for a full stroke, and you need to listen.” (See below for a key to warning signs of a TIA and how to respond.) 

Seizures

An “absence seizure,” caused by abnormal electrical activity in the brain, can cause temporary loss of consciousness. An at-hand observer might see the person suddenly stop their usual movement for 10 to 30 seconds. They may be unable to speak but can stand without falling. These symptoms mirror what people saw with McConnell.

There are other causes of freezing and blanking out, but the point is that any sudden change in mental status can be a red flag for a more serious problem. A comprehensive evaluation is called for to find the cause. This may include reviewing recent events in the person’s life, learning how symptoms began and developed, and conducting a neurological exam of sensory and motor systems. A psychiatric exam may be needed to see if there are underlying emotional or behavioral issues. Other useful tests might include brain imaging, an electrocardiogram (EKG), and an electroencephalogram (EEG).

As one expert put it, “The best treatment depends on finding the right cause.” And in keeping with that fact, it is also best not to wait out a freezing episode and assume it was nothing to worry about just because it dissipated. 

A Little More About TIAs

Odd, unexplained freezing or blanking out symptoms that last more than a few seconds could signal a transient ischemic attack, or TIA. According to the American Stroke Association (ASA), these events should be called “warning strokes” rather than ministrokes, because they can be harbingers of a much more serious stroke. Dr. Christopher Anderson, director of acute stroke services at Harvard-affiliated Massachusetts General Hospital, notes that if a blood clot blocking a brain artery doesn’t dissolve and remains in place for more than a few minutes, it can destroy brain cells in what’s called an ischemic stroke. These account for 87% of all strokes. As many as 17% of people who have a TIA will suffer a full-blown ischemic stroke within the next 90 days, with the greatest risk in the first week.

Gender Differences with TIAs

A recent study found that women with short-lived sensory or visual symptoms were less likely to be diagnosed with a TIA compared to men. It is speculated that because migraine headaches are more common in women, both the women and their doctors may be less likely to suspect a TIA in women with sensory or vision changes, which may occur with a migraine headache. “But it’s important to consider a TIA in all people with those symptoms, regardless of their gender,” says Dr. Anderson.

Other short-lived TIA symptoms may be easy to dismiss. Dr. Anderson says, “Sometimes, people will say, ‘That’s funny, I can’t feel one side of my face,’ and garble their words for a short time.” Or a person may repeatedly drop objects (such as a cooking utensil) but then be able to function normally after a few minutes. They don’t attribute these seemingly “ordinary” happenings to anything serious. Which can be a serious mistake.

BE-FAST When You See a Possible TIA or sStroke Happening

Julie Corliss, executive editor of the Harvard Heart Letter, points out that the American Stroke Association has coined the mnemonic FAST to help people recognize stroke symptoms. She explains that the first three letters — which stand for Face drooping, Arm weakness, and Speech difficulties — account for about 75% of the symptoms people experience during a stroke. (The T stands for Time, as in it’s time to call 911.)

She adds that some neurologists suggest adding two additional letters: B for balance and E for eyes. Dr. Anderson notes that Balance is a tricky one, because balance problems can occur due to a range of problems other than a stroke, especially in older people. With a stroke, balance problems rarely appear in isolation; they usually occur in tandem with other symptoms such as leg weakness or vision problems — the E component — such as reduced, blurry, or double vision.

Dr. Anderson goes on to say, “The simpler FAST makes sense for a public health campaign. But if you’re at risk [or with someone who is], knowing BE-FAST may be the most helpful, as it may help you recognize even more potential TIAs and strokes.” Also know that the leading cause of stroke is high blood pressure. Other risk factors include smoking, diabetes, physical inactivity, and obesity. People with heart disease (such as coronary artery disease, atrial fibrillation, and heart failure) face a higher-than-normal risk of stroke.