Which symptom indicates loss of inhibition in spastic dysarthria?

In spastic dysarthria, increased muscle tone is a key symptom that reflects the loss of inhibition in the neural pathways responsible for motor control. This condition often arises due to damage in areas of the brain that regulate voluntary movement, particularly the upper motor neurons. When there is a loss of inhibitory control, it results in hyperactivity of motor pathways, causing muscles to become excessively contracted, which is perceived as increased tone or rigidity.

Increased muscle tone affects speech production by reducing the ability to control movements, leading to a harsh or strained voice quality and difficulties with precision in articulation. Understanding this symptom is crucial for diagnosing and treating speech disorders associated with spastic dysarthria, as it provides insight into the underlying neurophysiological changes that impact motor function.