A reduction or absence of psychomotor activity that results in a masklike facial expression and impaired postural reflexes. A classic characteristic of Parkinson's disease.
A condition characterized by involuntary, purposeless, rapid motions such as flexing and extending the fingers, raising and lowering the shoulders, or grimacing.
A term describing any substance produced outside of the body that may be taken into the body (e.g. medication, food, or environmental toxin).
A common experience of patients taking medication for Parkinson's disease in which they experience periods of greater symptomatic control ("on" time) altering with periods of lesser symptomatic control ("off" time).
A slowly progressive, degenerative neurologic disorder characterized by resting tremor, pill-rolling of the fingers, masklike facies, shuffling gait, forward flexion of the trunk, loss of postural reflexes, and muscle rigidity and weakness.
A decrease or change in motor or muscle movements that leads to unsteadiness and hesitation in movement and gait when the individual starts or stops walking; occurs in Parkinson's disease.
Resistance of the muscles to passive movement; leads to the "cogwheel" rigidity seen in Parkinson's disease.