What is a key feature of muscle control in spastic dysarthria?

• A. Loss of inhibitory control
• B. Complete paralysis
• C. Increased flexibility
• D. Reduced muscle tone

Answer: (A)

A key feature of muscle control in spastic dysarthria is the loss of inhibitory control. In this condition, the upper motor neurons, which are responsible for providing inhibitory signals that help regulate muscle tone and movement, are damaged or dysfunctional. This leads to an excessive excitatory influence on the muscles, resulting in increased muscle tone or spasticity. As a result, individuals with spastic dysarthria may exhibit rigid or stiff muscle movements, making the coordinated control of speech muscles more challenging.

The other options do not accurately describe the characteristics of spastic dysarthria. Complete paralysis is not typical of this disorder, as individuals may still have some volitional control, albeit impaired. Similarly, increased flexibility is contrary to the hallmark of spasticity, which is characterized by tight and stiff muscles. Reduced muscle tone is not observed in spastic dysarthria; instead, the condition is associated with heightened muscle tone due to the underlying neurological dysfunction.