Trump, Biden, and Cognition

— Diagnosing impairment requires careful assessment by trained clinician, says Jason Karlawish, MD

MedpageToday
 Side by side photos of President Joe Biden and former President Donald Trump

The 2024 ballot may have the oldest pairing of presidential candidates, with President Joe Biden at age 81 and former President Donald Trump at age 77. Each candidate has publicly shown moments of forgetfulness in recent weeks, but what that means isn't clear.

The failure to remember a specific event or date may or may not point to cognitive problems, maintains geriatrician Jason Karlawish, MD, co-director of the Penn Memory Center at the University of Pennsylvania in Philadelphia, and author of The Problem of Alzheimer's: How Science, Culture, and Politics Turned a Rare Disease Into a Crisis and What We Can Do About It.

The diagnosis of cognitive impairment requires a careful assessment by a trained clinician, Karlawish says. In an exclusive interview with MedPage Today, he discusses the distinction between memory and forgetfulness, how clinicians determine cognitive impairment, and how popular media reports can muddy the picture.

Karlawish: There's a bit of a language mess in the media, but the mess is understandable. People who write about politics are reporting and commenting on what's essentially a topic of psychology and clinical neuroscience.

The most glaring example is that writers have been using terms like "senility." This term has had a variety of meanings over time. It's now an entirely historical term with no clinical, social, or public policy value. It doesn't advance or organize our thinking.

But it's a good example of how media reports and commentaries on both presidential candidates -- Biden and Trump -- amplify confusion. They use memory loss, forgetfulness, and dementia in a variety of different, sometimes interchangeable, or wrong ways.

MedPage Today: Both Biden and Trump have shown forgetfulness recently -- saying the wrong name, not knowing the right date when something happened.

Karlawish: Forgetfulness is not a term clinicians use, but it's certainly a term patients or family members often use to describe a concern about cognition. The task of a clinician is to figure out whether a person labeled with that folk psychology term in fact has cognitive impairment.

A complaint of forgetfulness may signify a variety of kinds of cognitive changes.

One is trouble with episodic memory; namely, a person witnesses or experiences an event, like a child's birthday party, and 1 week later, when asked about what they thought about the birthday party, they don't remember it.

I like the term episodic memory because it captures the specific kind of memory. We watch episodes of "Killing Eve" or "Bridgerton." If you're on season three, episode two, you remember what happened in episode one. That helps you understand what's going on in episode two.

It's particularly concerning if a person forgets recent episodes, events in the last week or month or so. In contrast, forgetting the name and classroom number of your first-grade teacher is a different kind of forgetting. That's remote memory and that is selectively pruned -- thank God -- by our brain.

An 80-year-old who can't remember his first-grade teacher has a very different memory loss than if he can't remember that 2 weeks ago he took a trip to New York City to see a show.

Another kind of forgetfulness is forgetting a word. There are at least two causes. One is people losing the meaning of words; they just don't know what that word is. This is a problem with semantic memory.

Semantic memory describes our knowledge of words and their meanings. For example, if I held up my ballpoint pen and asked, "What's this?" you'd reply, "A ballpoint pen." That's the semantic memory of what is the name of this long object with a point that spills out ink; that's a pen.

The second cause of forgetting a word is a problem with retrieving words. A person will struggle to find a word. If the experience is stressful, the struggle intensifies. Calm down, take some time, and the word comes to you.

Trouble retrieving words is a common age-related change in cognition. Age-related means "in the absence of disease." It describes the changes in the brain's synaptic architecture, the way neurons connect.

In contrast, losing the meaning of words is aphasia, which is a consequence of damage to the brain such as from a stroke or a disease like Alzheimer's.

MedPage Today: How do you know whether a complaint of forgetfulness is a symptom of cognitive decline?

Karlawish: I need a careful history and, guided by that history, cognitive testing to determine whether there's cognitive impairment, and if there is, what domain of cognition is impaired -- domains such as episodic memory or semantic memory.

Observing a person in the real world is one good way to detect cognitive problems. What a clinician does is talk to the person, and also to people who know the person well, and use these stories to find out what they've seen over time. Observations that suggest there have been changes in cognition guide whether to perform cognitive testing.

A work-up for cognitive impairment needs to recognize how problems outside the brain can cause impairments. Outside the brain refers to things like medications such as chronic use of benzodiazepines, fractured sleep, poor cardiovascular function, endocrinological disorders like hypothyroidism -- or several of these factors all working in combination to cause cognitive problems.

MedPage Today: What the public is seeing is Trump using the wrong name or Biden not remembering what year his son died. What might those mistakes mean?

Karlawish: A single observed moment may be a sign that cognitive impairments are present, but they are often neither sensitive or specific. You need to see more events that consistently show the same kind of change.

Recalling the year that your son died is an example of remote memory and how our brain elegantly edits what it chooses to remember. I can entirely understand why someone might not remember the year their child died. That's a trauma. One way we survive trauma is to prune particularly painful memories.

  • Judy George covers neurology and neuroscience news for MedPage Today, writing about brain aging, Alzheimer’s, dementia, MS, rare diseases, epilepsy, autism, headache, stroke, Parkinson’s, ALS, concussion, CTE, sleep, pain, and more. Follow