By Jacob Ahlstrom | Posted - Dec 23rd, 2020





No More Saying, “ALS Does Not Affect the Mind”!

Stephen Hawking lived with ALS (Amyotrophic Lateral Sclerosis) for 55 years. After he passed, his life was celebrated by recounting how brilliant his mind was even though it was trapped in a fallen body. It was originally thought that Amyotrophic Lateral Sclerosis (ALS) attacks the body, but leaves the mind unaffected. A recent article published in reminds us that ALS is not that simple. 

This false understanding of ALS, found in both medical and public literature, contradicts the research-based fact that ALS can affect the mind. With over a decade’s worth of research, there is no more ignoring the truth, ALS can cause cognitive and behavioral deficits in most patients.  

One known cognitive effect is called frontotemporal dementia and is found in 10% to 15% of ALS cases with another 33% to 50% of cases manifesting more subtle cognitive defects. Frontotemporal dementia is brain decay in the foremost part of the brain. This area of the brain is responsible for personality, behavior, and language processing.  

The question for researchers then is when are these cognitive symptoms most prevalent? In the study, Crockford and his team use a large sample size to answer this question: 

“Are the cognitive and behavioral symptoms in ALS more prevalent at more advanced stages of disease?”  


Using specific tests to identify a cognitive and behavioral decline in ALS patients, they were able to identify greater rates of cognitive loss and behavioral issues in further disease stages. The cognitive decline includes the loss of comprehension, language, and letter fluency. As for behavior, most caregivers reported their patient having at least one behavioral issue such as apathy (the loss of sympathy/empathy), different eating behaviors, lack of self-control, or psychosis (a.k.a. losing connection with reality).  

Using a tool called the King’s ALS Staging System the researchers investigated mental impairment during 4 different stages of ALS. After further investigation, the research team found that up to 80% of the patients suffered some sort of cognitive or behavioral loss.  

Table: Summary of cognitive, behavioral, and psychological issues across ALS King Stages  

Kings Stage 

Sage 1 (Disease Onset) 

Stage 2 (early progression)

Stage 3 (late progression) 

Stage 4 (nutritional or respiratory failure) 

Cognitive Impairment  





Behavioral Impairment 




















Table stage progressions measure ALS as it progresses from its first area of involvement with each stage progression reflecting the spread to a new area (upper limbs, lower limbs, or bulbar region)  

This is fairly substantial data, and it proves that cognitive and behavioral issues are common. So why do both professionals and patients believe that there is no evidence of a cognitive and behavioral decline in ALS patients? It may have to do with the fact that it took a century for researchers to acknowledge the fact that cognitive and behavioral issues occur in ALS. Now we have more than 10 years of research clarifying this truth. Researchers have even identified the gene responsible for frontotemporal dementia in ALS. Even so, the most common Google results still say that ALS does not affect the mind. More progressive literature will even claim that ALS “usually” does not affect the mind. But even these claims do not give us the whole truth because these symptoms are more common than people would like to admit. It is time to stop spreading this lie. 

In a survey of over 350 patients and caregivers, 90% reported not having been told that cognitive or psychological symptoms can arise in ALS by their doctor. Are we to assume that cognitive and behavioral issues are not a big enough problem to address compared to the weight of the other problems caused by ALS? Cognitive and behavioral impairment are just as much a part of the disease as any other aspect and ignoring these impairments makes it harder to fight this disease.  

Doctors have reported that their actual reason for keeping this information from patients is to spare patients from further distress. The outcome of this methodology is patients and caregivers who were told that the mind would go unaffected are unexpectedly faced with cognitive and behavioral symptoms without any tools or resources to respond. Because neurologists are not acknowledging the problem, caregivers and patients start blaming themselves, not the disease, when problems arise.  

Another issue is that neither patient nor caregiver knows to look for symptoms, much less how to identify them if they arise.  

In this same survey, 62% of patients and 71% of caregivers said they wished they had been told about these issues. It can be a hard truth to accept that this devilish disease has an even more sinister twist to it than we had originally understood, but it is the truth of the disease and ignoring this will only make things worse. We need to know what we are facing because we cannot beat a disease that we do not fully understand. We are the underdogs and we need to know everything we can about our undefeated opponent if we are going to stand a chance to fight it. Let’s do this together and fight ALS.  


Jacob Ahlstrom
About the Author

Jacob Ahlstrom - Jacob is a Neuroscience undergraduate at Brigham Young University. Jacob's interest in researching and writing about ALS is fueled by his hope to make the process easier for everyone else. Over the last year he has worked alongside Seth Christensen to find ways to educate and connect ALS patients.