While Parkinson’s disease is primarily recognized for how it affects the limbs through symptoms like tremors and stiffness, it also brings about significant changes to the face. These facial alterations are a common aspect of the condition, yet they are frequently misunderstood by the general public. The impacts on facial muscles can influence non-verbal communication, which in turn can affect social interactions.
Understanding the Mask-Like Expression
A defining facial symptom of Parkinson’s disease is a reduction in spontaneous facial expression, a condition known medically as hypomimia. This can manifest as a persistent serious, sad, or apathetic look that does not reflect the person’s actual emotional state. This “mask-like” appearance is often accompanied by a noticeably reduced blinking rate, which can give the impression of staring. The combination of a still face and infrequent blinking can make it difficult for others to interpret social cues.
The root cause of this masked expression is not emotional or psychological, but rather a motor symptom stemming from the disease’s core pathology. Parkinson’s is characterized by the loss of dopamine-producing nerve cells in the brain. Dopamine is a chemical messenger that helps regulate muscle movement throughout the body. Its deficiency leads to bradykinesia, or slowness of movement, and rigidity, which is muscle stiffness.
These same motor control issues that affect walking and balance also impact the 42 individual muscles of the face. The stiffness and slowness in these small muscles make it difficult to form expressions quickly or automatically, so smiling or frowning becomes a conscious and challenging effort. This symptom can appear gradually and its severity can range from a slight decrease in expressiveness to a near-complete immobilization of the face.
Related Oral and Swallowing Issues
Beyond the mask-like expression, Parkinson’s disease affects other muscles in the facial and oral areas. One common issue is sialorrhea, or drooling. This is not caused by an overproduction of saliva, but by the automatic act of swallowing becoming less frequent, allowing saliva to pool in the mouth and escape.
Another related symptom is hypophonia, which is characterized by soft, quiet speech. The voice may become monotone and breathy, losing its normal pitch and emotional inflection. The combination of a quiet, flat voice and a masked facial expression can make communication especially difficult, as both verbal and non-verbal emotional cues are diminished.
Many individuals experience dysphagia, or difficulty swallowing. This involves the complex coordination of muscles in the mouth and throat, which can be impaired by the disease. Difficulty swallowing can affect eating and drinking, and in some cases, may lead to more serious health concerns such as choking or aspiration, where food or liquid enters the lungs.
Managing Facial and Oral Symptoms
A proactive approach to managing these symptoms can help maintain muscle function and improve communication. Specific facial exercises, sometimes referred to as “facial aerobics,” can be beneficial. These exercises involve intentionally making exaggerated facial movements, such as holding a wide smile, puckering the lips, frowning intensely, and raising the eyebrows for several seconds. Performing these movements in front of a mirror can provide visual feedback and help ensure the expressions are being fully formed.
Speech therapy is important for managing oral motor symptoms. Programs like the Lee Silverman Voice Treatment (LSVT LOUD) are specifically designed for people with Parkinson’s. This therapy focuses on the principle of “thinking loud” to recalibrate the individual’s perception of their own voice volume, resulting in speech that is easier for others to hear and understand.
For managing sialorrhea, simple strategies can be effective. Consciously making an effort to swallow more frequently throughout the day can help manage saliva buildup. Chewing sugar-free gum or sucking on hard candy can also stimulate the swallowing reflex. Adjustments to a person’s primary Parkinson’s medications, which work to increase dopamine levels, may also lead to improvements in these facial and oral motor symptoms.