Dementia and the Brain
Module 3 - Lesson 1 of 5
Introduction
Different parts of the brain have different functions. Knowing how disease or injury affects different parts of the brain may help explain symptoms associated with dementia, traumatic brain injuries, and mental illness. Explaining something is different from understanding how a person experiences it, but explaining is a good place to start.
Dig In
The Seven Areas of the Brain
What does each of these do?
- Frontal Lobe - Allows us to reason, plan, move, express emotions, and solve problems. It is often called the 'CEO of the brain.'
- Parietal Lobe - Underlies orientation to time, place and person, and recognition
- Occipital Lobe - Helps make sense of what we see.
- Temporal Lobe - Helps perceive the world, recognize sounds, store memory, and use speech.
- Brain stem - Regulates basic vital life functions such as breathing, heartbeat, and blood pressure.
- Hippocampus - Converts short-term memory to more permanent memory, and helps recall spatial relationships in the world around us. It is critical for new learning.
- Amygdala - Regulates emotional responses, especially the fear response.
Healthy and Diseased Brains
If you could slice a brain like a loaf of bread and look at the surface, this image shows how it would look:
On the left side of the picture, a slice of a normal brain is shown. On the right side, you see the changes in the brain of a person with Alzheimer’s.
Notice how brain has shrunk and the grooves (sulci) are wider and deeper due to the death of brain cells. Cells die because of a buildup of plaques and tangles. Fewer brain cells mean fewer chemicals (neurotransmitters). This makes it harder for cells to communicate with one another. Medications used to slow Alzheimer's progress work by making more of those neurotransmitters available.
Early Symptoms of Alzheimer's
Damage to the brain cells in Alzheimer's usually starts in the hippocampus; therefore, the earliest symptoms of dementia due to Alzheimer's will be problems with short-term memory and new learning.
Depending on which areas of the brain are affected, you may notice other symptoms in a person living with dementia:
- Repeats same questions
- Gets lost easily
- Likes to walk
- Has trouble following directions
- Gets disoriented about time, people, and places
- Becomes frustrated while doing tasks if hurried
- Doesn’t recognize you, themselves or their family
- Neglects personal safety, hygiene, and nutrition
Wrap Up: Lesson 1
Different parts of the brain are responsible for different actions. Dementia is a brain disorder with many causes. Some causes, like drugs and depression, may be reversible. Other causes, like Alzheimer's or vascular disease, are irreversible. Dementia affects all parts of the brain over time.