Apraxia is a neurological symptom that involves the inability to perform purposeful movements on demand. People with apraxia are not physically paralyzed, but they lack the ability to control the muscles required to perform certain tasks. It is usually the result of damage to the parietal lobe of the brain, which is associated with planning and executing movements.
People with apraxia may also experience seizures, aphasia (an inability to speak and understand language), memory loss and confusion.
There are various kinds of apraxia that affect different types of movement, including:
- Ideomotor apraxia. Inability to mimic or perform a movement (e.g. hammer a nail, brush hair, blow out a match, cough) in response to a verbal command.
- Ideational apraxia. Inability to correctly perform a series of movements to accomplish certain tasks (e.g., writing, bathing, dressing, eating or brushing teeth). Patients also may not know how to appropriately use certain tools or objects. For instance, a pen may be used in the manner of a comb.
- Verbal apraxia. Inability to coordinate lip, mouth and tongue movements in order to speak. People with verbal apraxia may be unable to say a word correctly and consistently (they can say a word correctly one moment but not the next).
- Buccofacial apraxia. Inability to perform movements of the face and mouth (without typically affecting a patient’s ability to speak). Patients with verbal apraxia may not be able to lick their lips, blow, cough or wink upon verbal command.
Additional types of apraxia that some experts believe should not be considered true forms of apraxia include constructional apraxia, limb-kinetic apraxia and oculomotor apraxia.
Apraxia can be caused by anything that causes neurological damage. This may include certain developmental disorders present at birth, traumatic brain injury and dementia. Treatment for apraxia is focused on rehabilitating the patient and attempting to recover motor skills. This may or may not be successful, depending on the type of apraxia and the patient’s age and health. People with apraxia may be dependent on caregivers for many aspects of their daily lives.
Apraxia is the inability to perform purposeful movements on demand. It is a neurological symptom, rather than a muscular one. It occurs in people whose muscles and senses are properly functioning. People who experience apraxia understand the command and are familiar with the task involved, but are unable to coordinate their movements to carry out the activity.
Apraxia is a symptom of neurological damage that most often occurs as a result of damage to the parietal lobe of the brain. This part of the brain is associated with planning and executing skilled movements of the eyes and limbs, as well as voice muscles. In some cases, apraxia can occur when other parts of the brain are damaged.
People who experience apraxia may have trouble performing complex tasks such bathing or dressing. They may also have difficulties using tools (e.g. scissors, pencils, hammers) or they may use tools inappropriately (e.g. attempting to write with a screwdriver). In some cases, apraxia may affect the ability to purposefully move the muscles of the lips, mouth and tongue, making it difficult to talk. When any of these difficulties are mild rather than severe, it is called dyspraxia.
Apraxia does not indicate reduced intelligence or mental capacity. However, in some cases, it may indicate certain disorders (e.g., dementia) that can result in a decline in mental capacity. Most often, patients are aware of the apraxia and their inability to perform certain tasks, which can cause them to become frustrated and depressed. In some cases, the patient or caregiver may be unaware of the true extent of the apraxia. This may happen if the patient becomes uninterested and lethargic in daily activities, as often occurs in the latter stages of Alzheimer’s disease or following a stroke.
Other symptoms related to apraxia
People who experience apraxia may also experience additional symptoms of neurological damage, including:
- Aphasia. Aphasia is a loss of the ability to use and understand language. It is the result of damage to the part of the brain (usually the left side) that is associated with language. Some people describe aphasia as listening to a foreign language. Both aphasia and apraxia are common symptoms of a stroke.
- Ataxia. This inability to coordinate or control muscle movements may sometimes also occur in patients with apraxia.
- Seizures. Damage that causes apraxia may also trigger seizures. Seizures occur when the neurons (nerve cells) in the brain suddenly increase their activity, causing an electrical storm that can overwhelm the brain.
- Memory loss and confusion. Apraxia that is a symptom of certain conditions such as Alzheimer’s disease, dementia or a traumatic brain injury, may be accompanied by some degree of memory loss and confusion. This may be temporary, permanent or degenerative.
In some cases, people who experience apraxia may experience weakness, numbness or tingling in their affected body parts.
Types and differences of apraxia
There are many different types of apraxia. A patient may experience just one type of apraxia or more than one type at the same time. In addition, the type and severity of dysfunction associated with these types can vary from person to person.
Types of apraxia include:
- Ideomotor apraxia. Inability to mimic or perform a task or movement (e.g. hammer a nail, brush hair, blow out a match, cough) upon verbal command. Patients may be able to perform an activity when it occurs spontaneously, but not when suggested by others. For example, a patient may be able to scratch his or her head spontaneously, but be unable to do so when asked. Ideomotor apraxia is the most common type of apraxia seen in clinical settings.
- Ideational apraxia (also known as conceptional apraxia). Inability to perform tasks that require a specific series of events to occur, or a loss of knowledge of how tools or certain objects are to be used. For example, the various steps involved with using a pen and writing (e.g., picking up pen, removing cap, placing cap on other end, placing pen tip on paper) may be confused. A patient with ideational apraxia may attempt to write with the pen cap on, or with the wrong end of the pen. Patients may have no trouble performing the individual steps, but are not able to put the steps together appropriately (e.g., putting on socks before shoes). Additional types of tasks that may be difficult for patients with ideational apraxia include bathing, eating and brushing teeth.
- Verbal apraxia. Inability to coordinate lip, mouth and tongue movements in order to speak. Contrary to how it may appear, people with verbal apraxia do not have any muscular deficiencies in their face. People with verbal apraxia may be unable to say a word correctly or they may be able to say a word correctly one day but not the next. Often, patients cannot put sounds and syllables in correct order to form words. Long, complex words may be more difficult than short, simple words. Patients with verbal apraxia may appear to be fumbling for the correct word or sound while speaking. They may also be unable to add the correct emphasis of certain sounds or words to convey meaning while speaking.
Vocal dysfunction experienced can range from mild (e.g., a few, occasional speech problems) to severe (e.g., unable to produce any intelligible sounds). Verbal apraxia may be one of the most common types of apraxia, according to the National Organization for Rare Disorders. Verbal apraxia can be acquired as a result of injury or disease, or it may be a developmental disability (e.g., a birth defect). Acquired verbal apraxia is more common in adults.
- Buccofacial apraxia (also known as orofacial apraxia) involves difficulty with movements of the face and mouth but does not typically affect a patient’s ability to speak. Verbal apraxia is sometimes considered a more severe form of buccofacial apraxia. This type of apraxia involves the inability to perform facial movements upon verbal command, such as whistling, coughing, winking, blowing or licking the lips. This is a very common type of apraxia, according to National Institute of Neurological Disorders and Stroke (NINDS).
Some additional types of apraxia are not considered true forms of apraxia by some experts. This is because actions may be performed, albeit not perfectly. These include the following:
- Constructional apraxia. Inability to draw, copy or construct simple figures. People with constructional apraxia may have difficulty imagining the spatial relationship between objects. For example, a patient with constructional apraxia may draw several unconnected straight lines when instructed to draw a “cube.” In addition, patients with this type of apraxia may have difficulty following a map.
- Limb-kinetic apraxia. Inability to make precise and exact movements with fingers, hands, arms and legs. Patients with this type of apraxia typically appear to operate slowly or clumsily with tools and objects. They may not be able to move their fingers quickly (e.g., tapping fingers) or to grasp objects with their fingers.
- Oculomotor apraxia. Difficulty in moving the eyes (e.g., lifting the eyelids) upon verbal command.
Potential causes of apraxia
Any disease or condition that affects the parietal lobe or other areas of the brain associated with motor function can produce a variety of symptoms, including apraxia. These conditions may include:
- Childhood speech apraxia. The most common cause of apraxia in children, childhood speech apraxia is a developmental disorder that is present from birth. It typically affects more boys than girls and is thought to be caused by some kind of neurological dysfunction. However, evidence of brain lesions or other differences in brain structure are not present in imaging tests. Childhood speech apraxia is more common in families with a history of communication disorders, leading some to suggest that genetics may play a role.
- Dementia. Collection of symptoms that include memory loss and reduced mental capabilities (e.g., intellectual functioning, reasoning). Apraxia is often associated with dementia. Many different conditions can cause dementia, including Alzheimer’s disease. Alzheimer’s disease is the most common cause of dementia among people over the age of 65, according to the National Institute of Neurological Disorders and Stroke (NINDS). Alzheimer’s disease occurs when neurons in the brain die or break their connections with other neurons. When this happens in the neural networks or parts of the brain associated with motor function, apraxia may occur.
- Stroke. A stroke is a life-threatening event in which part of the brain is deprived of adequate oxygen (hypoxia). Also known as a cerebrovascular accident or a “brain attack,” a stroke occurs when a blood vessel in the brain bursts or becomes clogged by a blood clot or other mass. This prevents oxygen and other nutrients from getting to nerve cells in the affected area of the brain. These nerve cells can die within minutes, and the area of the body that they control can cease to function. A stroke can cause a number of symptoms, including apraxia.
- Traumatic brain injury. Apraxia may occur if a traumatic head injury damages the part of the brain that is associated with motor function.
- Brain tumor. Tumors can cause pressure to build in the brain and disrupt neuron functioning. This can lead to apraxia, which may come on suddenly or gradually. In some cases, removal of the tumor may restore motor function, although sometimes the damage is permanent.
- Corticobasal ganglionic degeneration. This is a degenerative neurological disorder that is more prevalent in people over 60. People with corticobasal degeneration experience a slow decline in cognitive ability because of the gradual death of brain cells in the cerebral cortex and the basal ganglia. If the brain cells that affect motor functioning are affected, it can cause apraxia.
Treatment and prevention of apraxia
Treatment for apraxia usually relies on an accurate diagnosis of the underlying cause. Patients may not realize that they have apraxia until they are asked to perform a task. Once apraxia has been identified in a patient, a physician may rule out potential contributing factors, such as muscle weakness or language and comprehension problems, which may be interfering with the patient’s ability to perform the task. A physician may refer the patient to a neurologist. Several imaging tests may be conducted, including computed axial tomography (CAT) scans, MRIs (magnetic resonance imaging) and x-rays. Blood tests or a spinal tap may also be conducted.
Once the underlying cause is diagnosed, treatment for apraxia is aimed at rehabilitating patients and recovering their motor function abilities. This may include physical therapy and occupational therapy. Apraxia caused by certain neurological disorders may require treating the underlying condition. What treatment is used will depend on the disorder or condition causing the apraxia. The recovery process can be long and frustrating, after which time the patient may or may not recover complete control of motor skills. Treatment is more successful if it is started as soon as possible.
Other factors which affect recovery include the extent of the neurological damage, the level of a patient’s motivation, and the age and health of the patient. Children who are born with childhood speech apraxia can be treated with speech/language therapy but may never speak as fluently as other children. In severe cases, verbal apraxia that results in an inability to communicate effectively may require the use of gestures, sign language or other means of communication. Devices that can aid communication (e.g., a computer that writes and produces speech) may also be required.
An important part of the recovery process for the patient is the education of the patient’s family and friends. Caregivers and others should be aware of the nature of the patient’s limitations and should be educated about how to communicate with the patient, especially in the case of verbal apraxia. People with apraxia may become dependent on caregivers for many aspects of their daily life.
In most cases, apraxia cannot be prevented. Because some cases of apraxia are caused by stroke, one way of preventing apraxia may be to protect the body against stroke. This may include eating a healthy diet, quitting smoking and controlling high blood pressure. People can also prevent head injuries, which may cause apraxia, by wearing a seatbelt while traveling in a car and wearing protective head gear while operating a motorcycle or while playing contact sports.
Questions for your doctor regarding apraxia
Preparing questions in advance can help patients to have more meaningful discussions with healthcare professionals regarding their condition. Patients may wish to ask their doctor the following questions related to apraxia:
- Why do you think I have apraxia? Could it be something else?
- What type of apraxia do I have?
- Will my apraxia get worse?
- What do you think is causing my apraxia?
- Can the cause of my apraxia be treated? How?
- Do I have brain damage that may be causing my apraxia? Is this damage permanent?
- Are there certain activities that should be monitored or restricted (e.g., dressing, cooking)?
- Will physical, occupational or speech therapy help me? Can you recommend a therapist?
- Will I be able to regain motor function?
- Would psychological counseling, either individually or in a group, be helpful?
- Given my current limitation, can you recommend strategies to help me communicate with others?