Verified by 
In our last post, we began our discussion of why language breaks down in dementia. In this week’s post, we will continue this exploration by focusing on the interaction between communication, the body, and how both are affected by dementia.
Slurred speech suggests problems with control of the voice muscles.
Speech arises from the coordinated actions of the lips, mouth, tongue, and vocal cords. When dementia causes damage to the part of the frontal lobes that sends the signals to these voice muscles or to the connections between them, difficulty articulating words and sentences will occur. Strokes are the most common disorder that disrupts this part of the brain, so slurred speech is most commonly seen in vascular dementia, although several other causes of dementia may also cause slurred speech, as can other neurologic disorders. When people have slurred speech due to dementia or another neurologic problem, it is often worse if someone is sick, drinking alcohol, or even just tired.
The meaning of words and objects can deteriorate in dementia
We discussed last week how the temporal lobes are our collection of knowledge, with the left temporal lobe storing our vocabulary of people and objects, and the right temporal lobe containing different qualities of those people and objects. It should then not be surprising that when dementia affects the temporal lobes, knowledge of people and objects become lost. When this loss occurs, not only is there difficulty searching for the name of an object, there is also difficulty in understanding what the object is, what qualities it has, and what it is used for. Note that although word-finding difficulties occur in any stage of dementia, loss of object knowledge generally occurs in the middle or late stages.
The right temporal lobe helps with emotional and other non-linguistic parts of communication
Think about how you could say the same sentence in three different ways:
- As a simple statement: She went to the store.
- As a question: She went to the store?
- With anger: She went to the store!
It is your right temporal lobe that can comprehend and help communicate different meanings even when the words spoken are the same. It also understands people and things, but instead of understanding who and what they are, it is concerned with how you feel about them—such as whether you love them, are curious about them, or find them annoying—in addition to what qualities they have as we mentioned above.
Non-linguistic and non-verbal communication are often preserved in dementia
Emotional and other aspects of non-linguistic communication are often preserved well into the moderate and severe stages of dementia. So, even when your loved one may not understand what you are saying, they will likely understand the kindness in your tone of voice, the happiness of your smile, and the caring in your touch. If, on the other hand, you are feeling frustrated or annoyed or angry, you may also be expressing these emotions through your face, body language, and tone of voice. Think about how you might communicate with someone who speaks a different language and knows just a few words of English. While you are speaking the words, make sure that you are also using your actions and tone of voice to demonstrate what you are trying to say.
Key questions
Q: So, now he has the hearing aids, but he still doesn’t seem to understand what I’m saying.
- As dementia progresses, many people have trouble understanding spoken language due to the disease affecting the temporal lobes. Try to use simpler words and sentence structure. The tone of voice, facial expressions, and actions may allow you to communicate even if comprehending words is completely gone.
Q: My husband’s speech is so slurred when he is tired that I can’t understand what he is saying. He sounds like a drunk but I know he hasn’t had any alcohol. What’s going on?
- Several dementias, including vascular dementia, can cause slurred speech. There are other causes, such as medication side effects, so it’s always important to make sure that your loved one sees their doctor if their speech is slurred.
- If their speech suddenly becomes slurred over a matter of minutes (or they wake up that way), they should immediately go to their doctor or the emergency room, as it could be due to a stroke.
Stay tuned for my next post, where I will discuss how dementia affects vision.
© Andrew E. Budson, MD, 2019, all rights reserved.
References
Budson AE, O’Connor MK. Seven Steps to Managing Your Memory: What’s Normal, What’s Not, and What to Do About It, New York: Oxford University Press, 2017.
Budson AE, Solomon PR. Memory Loss, Alzheimer’s Disease, & Dementia: A Practical Guide for Clinicians, 2nd Edition, Philadelphia: Elsevier Inc., 2016.
