Ch. 12 The Central Nervous System

Amerman - Human Anatomy & Physiology 2nd Edition

Amerman2nd EditionHuman Anatomy & PhysiologyISBN: 9780136873822Not the one you use?Change textbook

Amerman 2nd Edition

Ch. 12 The Central Nervous System

Problem L2.1

Chapter 12, Problem L2.1

Huntington's disease is characterized by a loss of normal inhibition mediated by the basal nuclei. Predict the symptoms you are likely to see with this disease.

Verified step by step guidance

Understand the role of the basal nuclei: The basal nuclei are clusters of neurons in the brain that play a critical role in regulating motor control, coordination, and inhibition of unnecessary movements. They help ensure smooth and purposeful movements by suppressing involuntary or excessive motor activity.

Recognize the impact of Huntington's disease: Huntington's disease is a genetic disorder that leads to the degeneration of neurons in the basal nuclei, particularly in the striatum. This degeneration disrupts the normal inhibitory function of the basal nuclei, leading to a loss of control over motor activity.

Predict motor symptoms: Without proper inhibition from the basal nuclei, patients are likely to experience involuntary movements known as chorea. These movements are jerky, uncoordinated, and can affect various parts of the body, including the limbs, face, and trunk.

Consider cognitive and behavioral symptoms: In addition to motor dysfunction, the degeneration of neurons in Huntington's disease can affect cognitive processes and emotional regulation. Symptoms may include difficulty with decision-making, memory loss, mood swings, and depression.

Summarize the progression of symptoms: Huntington's disease is progressive, meaning symptoms worsen over time. Early stages may involve subtle motor or cognitive changes, while later stages can lead to severe motor impairment, difficulty swallowing, and significant cognitive decline.

Verified video answer for a similar problem:

This video solution was recommended by our tutors as helpful for the problem above.

Was this helpful?

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Basal Nuclei Function

The basal nuclei, or basal ganglia, are a group of nuclei in the brain that play a crucial role in coordinating movement and regulating voluntary motor control. They help inhibit unwanted movements and facilitate desired actions. Dysfunction in these structures can lead to motor symptoms such as tremors, rigidity, and involuntary movements, which are characteristic of disorders like Huntington's disease.

Huntington's Disease Pathophysiology

Huntington's disease is a genetic neurodegenerative disorder caused by the mutation of the HTT gene, leading to the progressive degeneration of neurons, particularly in the basal ganglia. This degeneration results in a loss of inhibitory control over motor functions, leading to symptoms such as chorea (involuntary jerking movements), cognitive decline, and psychiatric issues. Understanding this pathophysiology is essential for predicting the symptoms associated with the disease.

Motor Symptoms of Huntington's Disease

The motor symptoms of Huntington's disease primarily include chorea, which is characterized by irregular, unpredictable movements, and dystonia, which involves sustained muscle contractions. As the disease progresses, patients may also experience bradykinesia (slowness of movement) and rigidity. These symptoms arise from the imbalance between excitatory and inhibitory signals in the brain, particularly due to the loss of function in the basal nuclei.

Recommended video:

4:31

Primary Motor Cortex & Primary Somatosensory Cortex

Related Practice

Textbook Question

Mark the following statements about the brain as true or false. If a statement is false, correct it to make a true statement.

The four main components of the brain are the cerebrum, the diencephalon, the cerebellum, and the brainstem.

Textbook Question

Mark the following statements about the brain as true or false. If a statement is false, correct it to make a true statement.

The right and left lateral ventricles are the largest of the ventricles in the brain and are located in the diencephalon.

views

Textbook Question

Mark the following statements about the brain as true or false. If a statement is false, correct it to make a true statement.

Humans use only 10% of their brains.

views

Textbook Question

Why must a cell body be intact for an axon to regenerate? (Hint: What structure is housed only in the cell body, and what are its functions?)

views

Textbook Question

How could you tell the difference between an injury that damaged the cerebellum and one that damaged the basal nuclei?

views

Textbook Question

Why do injuries to the hippocampus interfere with the formation of new declarative memories but do not impact memories already encoded in long-term memory? Why do such injuries not affect the formation of nondeclarative memories?

views