Amyotrophic lateral sclerosis (ALS)

Definition

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease that affects motor neurons in the brain and spinal cord, leading to muscle weakness and atrophy. The condition is characterized by the gradual degeneration and death of these motor neurons, which ultimately results in the loss of voluntary muscle control, impacting mobility, speech, and swallowing.

5 Must Know Facts For Your Next Test

1. ALS is often referred to as Lou Gehrig's disease after the famous baseball player who was diagnosed with it.
2. The exact cause of ALS remains unclear, but both genetic and environmental factors are thought to play a role in its development.
3. There are two types of ALS: sporadic, which is the most common form, and familial, which runs in families and is caused by inherited gene mutations.
4. Symptoms typically begin with muscle twitching and weakness, leading to difficulty in speaking, swallowing, and eventually breathing.
5. Currently, there is no cure for ALS, but treatments focus on managing symptoms and improving quality of life for those affected.

Review Questions

• How does the degeneration of motor neurons in ALS affect muscle function and overall physical abilities?
  • In ALS, the degeneration of motor neurons disrupts the communication between the brain and the muscles. As these neurons die, the brain's ability to initiate voluntary movements diminishes, leading to muscle weakness and atrophy. This affects physical abilities by making it increasingly difficult for individuals to perform basic tasks such as walking, speaking, and even breathing as the disease progresses.
• What are the differences between sporadic and familial ALS, particularly in terms of their genetic implications?
  • Sporadic ALS occurs without a known family history and is the most common form of the disease, accounting for about 90-95% of cases. In contrast, familial ALS is hereditary and results from specific gene mutations that can be passed down through generations. Understanding these differences helps in identifying individuals at risk for familial ALS and highlights the role genetics may play in certain cases of sporadic ALS.
• Evaluate the current treatment options for ALS patients and their effectiveness in managing the disease's progression.
  • Current treatment options for ALS primarily focus on symptom management rather than curing the disease. Medications like riluzole can slow disease progression modestly by reducing damage to motor neurons. Supportive therapies, including physical therapy, occupational therapy, and speech therapy, aim to maintain quality of life and functionality for as long as possible. While these treatments can help manage symptoms and improve daily living activities, they do not halt the progression of ALS itself, indicating a significant need for further research into more effective therapies.

Related terms

Motor Neurons: Nerve cells that transmit signals from the brain and spinal cord to muscles, enabling movement.

Skeletal Muscle Atrophy: The wasting or loss of muscle tissue due to disuse, malnutrition, or diseases such as ALS.

Gene Mutations: Changes in the DNA sequence that can lead to diseases, including certain hereditary forms of ALS linked to specific genes.