Tremor causes may be a normal bodily response or may be due to a more serious issue, such as a neurological condition. There are also at least four main tremor types and each one is triggered by a different condition. Some tremor causes are due to conditions, such as Parkinson’s disease, dystonia, multiple sclerosis or alcoholism, while others are due to the body’s response to gravity or may be hereditary.
A tremor is an uncontrolled and involuntary movement, which includes muscle contraction. The four main tremor types are resting tremor, postural tremor, essential tremor and intention tremor. Just as distinct categories of tremors exist, so do distinct tremor causes and characteristics.
A resting tremor is one that occurs when the body is at rest. These tremors tend to not just cause involuntary movement, but also involve muscle contraction and appear to be less active when the body is moving. One of the most common tremor causes for this category is a neurological disorder known as Parkinson’s disease.
A postural tremor occurs when the body is held in a certain position against gravity. For instance, a postural tremor may be noticed when attempting to extend the arms in front of the body and hold them in that position for a period of time. A person’s arms may begin to involuntarily shake no matter how much concentration is projected into steadying the limbs. Tremor causes for this type are simply the body’s reaction to working against gravity. Postural tremors may, however, also be found in people with neurological damage.
An essential tremor is the type that more commonly affects older people. It can, however, affect anyone at any age and appears to even be hereditary in some cases. Other tremor causes for this type are not completely known although researchers do know that essential tremors occur more frequently in people with a neurological disorder, such as dystonia.
An intention tremor is also known as a kinetic tremor. This type generally follows intentional movement and occurs in one specific part of the body. For instance, an intention tremor may occur in the hands after typing a letter or in the arms after holding a child. This type also goes away once the limb is resting again. Tremor causes for kinetic types may include multiple sclerosis, alcoholism or stroke.
In cases of brain disorders or disease, underlying tremor causes may pose a threat to an individual’s health and quality of life, but tremors, alone, are not life-threatening. A person may also be affected by more than one tremor type at a time. For instance, a person with a neurological disorder may display symptoms of a resting tremor as well as an essential tremor. Even perfectly healthy people may, from time to time, experience a postural tremor as well as an intention tremor.