Essay: Distinguish between the different forms of apraxia. How may they be best explained?

Title: Apraxia

Distinguish between the different forms of apraxia. How may they be best explained?

Apraxia is a disorder of the nervous system in which an individual is unable to perform tasks or movements when asked, irrespective of the fact that he has understood the command and is willing to do it. Not only this, the muscles required to perform the task are also functional and the task is not new to the patient either.

Apraxia is the inability to carry out useful or skilled acts while motor power and mental capacity remain intact. The areas of the brain affected all are parts of the cerebral cortex and include the parietal lobes, frontal lobes (especially the premotor cortex, supplementary motor area), or corpus callosum and rarely some part of temporal lobe. These areas can be of the dominant side or the non-dominant side.

These areas of the brain control movement of the voluntary muscles. Any damage to these, results in the disturbance in performance of movements intended by an individual.  Apraxia can arise from many diseases or maybe a result of trauma to the brain. The damage affects the brain’s ability to correctly signal instructions to the body. There are several conditions that can lead to apraxia but most common are stroke and head injury.It is not age-specific that is apraxia can occur to newborn as well as to a man of age 60. Therefore, it is a disease that can affect people of all ages. Heilman (2008), defined apraxia in negative terms, characterizing it as “a disorder of skilled movement not caused by weakness, akinesia, differentiation, abnormal tone or posture, movement disorders such as tremors or chorea, intellectual deterioration, poor comprehension, or uncooperativeness (Heilman, 2008).”

Signs and symptoms:

A person suffering from apraxia has no physical paralysis yet he/she would be unable to perform simple voluntary movements like combing hair. Prompts or commands are heard but not executed. The movements made somehow are very clumsy, inappropriate and not in control. Apraxia also causes movements that are completely unintentional. There are speech disturbances and gait disturbances. Based on areas of body affected by the disease, apraxia has been divided into several types which may or may not occur at the same time in one patient. The forms of apraxia are enlisted below:

 Oculomotor apraxia

 Bucco-facial or orofacial apraxia

 Limb-kinetic apraxia

 Ideational apraxia

 Ideomotor apraxia

 Apraxia of speech or verbal apraxia

 Constructional apraxia

Oculomotor Apraxia:

Ocular motor apraxia is defined the absence or disturbance in the control of voluntary purposeful eye movements. Individuals suffering from oculomotor apraxia find it difficult to move their eyes in a particular direction. In other words, their saccades (i.e. the normal, quick, simultaneous movement of both eyes in the same direction) are not normal. Because of this, people with oculomotor apraxia have to turn their head to see things in their side (peripheral) vision.Nonetheless, vertical eye movements are unaffected. This condition is accompanied with the difficulty to coordinate movements which is known as ataxia (Anheim, Mathieu, et al. 2008).

There is another condition also known as apraxia of eyelid opening. It is characterized by inability of voluntarily open the eyes. The pathophysiology is not much understood but it does include the inhibition of the muscle responsible for opening of the eye lid that islevatorpalpabrae leading to this condition   (Anheim, Mathieu, et al. 2008).

Bucco-facial or Orofacial Apraxia:

This is the most commonly occurring form of apraxia. Oral apraxia is an inability to make intentional movements involving the buccal or oral muscles. A person with this problem would be unable to protrude his tongue but will be able to do reflexively. Hence these don’t include the movements required for one to speak.Similarly, movements of the Bucco-facial muscles such as whistling or licking of lipscannot be performed by the affected individual. Oral apraxia may also be mistaken for aphasia, because some tests for aphasia also include performing movements such as ‘lick your lips’. (Rothi, 2014).

Limb-kinetic Apraxia:

Loss of hand and finger dexterity resulting from inability to connect or isolate individual movements. Limb-kinetic apraxia can be characterized by difficulty in making precise movements with the limbs such as an arm or leg. This can include using tools such as screwdriver or a toothbrush or threading a needle and picking up small objects. Hence all fine motor skills are greatly affected as movements become disoriented and mutilated.

An individual suffering from this type of apraxia is not able to perform even the simplest of daily routine tasks. It becomes impossible for him/her to button a shirt or tie a shoelace. This loss of fine motor skills is a very huge cause of dependence in such patients. They are unable to lead an independent life and may require the help of a nurse or all time care taker to perform these tasks (Vanbellingen, Tim, et al., 2010).

Ideational apraxia:

The patient suffering from ideational apraxia does not know what to do. This terminology can be confusing not only because definitions of ideational and conceptual apraxia vary among authors (Ochipa et al., 2012) states that because a distinction between the two is debated by some. Still it may be defined as impairment in carrying out sequences of actions requiring the use of various objects in the correct order to achieve an intended purpose accompanied by the loss of tool action knowledge. In other words, it is the loss of perception of the use of the tool and its performance. Leading to disoriented and inappropriate movements initiated and executed when handed over with one. An example could be combing of hair with a tooth brush or trying to scribble when a screwdriver is given in hand of an individual suffering from ideational apraxia. Characteristics of this disorder include a disturbance in the concept of the sequential organization of voluntary actions (Fukutake, 2013). Some clinical examples are as follows:

The patient does not know what to do with toothbrush, toothpaste or shaving cream. He uses tools inappropriately (i.e. smears toothpaste on face, uses washcloth to wash sink instead of face, eats soap, toothbrush as hairbrush. He sequences activities steps incorrectly so that there are errors in the result of task (i.e. put socks on top of shoes, washing body without soap, attempting to drink milk without opening container).

Liepmann was the first to conduct tests on these patients in his laboratory (Hanna &Rothi, 2010).  He discovered that patients with ideational apraxia made sequential errors. His experiments included performing simple acts such as lighting a candle. The patients were provided with a match box and a candle. Some patients tried lighting the candle with the match box itself. Others brought the match stick to the candle without lighting it first. This showed that the patients could accurately identify the objects but were not able to peform the designated taks. There was a deficit in the execution of a particular act despite knowing and understanding the functions of the tools especially in a multiple-object task (Cooper, 2008).

For ideational apraxia, not one anatomical area has been identified, but damage to left hemisphere is most common. The damage therefore, is typically thought to involve left parieto-occipital and parieto-temporal regions. It can, rarely though also be due to the injury of left frontal, frontotemporal and temporal regions with or without sub-cortical involvement. Collectively, it an autonomous syndrome, associated with damage in the left hemisphere affecting semantic memory rather than the motor co-ordination.

Since damage to the brain is irreversible, ideational apraxia hasn’t had a treament plan yet established. Nonetheless, phycial and ocuupational therapy is avaible to delay and slow down the progression of the disease. Hence its treament approach is in many ways similar to that of ideomotor apraxia (Unsworth, 2007).

Ideomotor Apraxia:

Ideomotor apraxia is the disorder of goal-directed movement. Patient knows what to do but not how to do it. Disturbance of timing, sequencing and spatial organization of gestural movement.

Anatomically there are diverse lesions in left hemisphere (parietal lobe, frontal lobe, and bundles connecting the two) and may also involve the thalamus and basal ganlia. Right handed patients with unilateral lesions of the left hemisphere suffer from bilateral defects, which are less severe in left limb.

Ideomotor apraxia impinges on one’s ability to carry out ordinary, well-known actions on command. It is hence the disturbance of voluntary movement in which a person cannot translate and idea into movement, i.e. breakdown with the planning of the task despite understanding the concept of the task.

Such a patient may experience following difficulties:

1. Sequencing of movements

2. Choppy, clumsy, or irregular movements

3. Inability to adjust grasp during tool

4. Unable to perform task on command

The patient may describe the method, through which the task can be performed, know what an object is, and can still perform automatic movements, such as cutting with scissors. However, their disturbance when asked to do something upon request for example poor ability to copy or gesture, such as wave good bye.

Ideomotor clinical examples include: Awkward or clumsy movements, Difficulties when planning movements to cross midline (i.e. adjusting the grasp on a hairbrush when moving it from one side of the head to other to turn the bristles toward the hair),  difficulty in orienting the upper extremity or hand to conform to objects such as picking up a juice bottle with the radial side of the hand down or via picking up bottle with a pinch grip on the lip of the bottle instead of a typical cylindrical grip on the base   (Manuel, Aurelie L., et al. 2012).

Apraxia of speech or Verbal Apraxia:

Verbal apraxia is a disorder involving difficulty coordinating mouth and speech movements. It is referred to as apraxia of speech by organizations including the American Speech Language Hearing Association (ASHA).  By definition it is “neurologic speech disorder that reflects an impaired capacity to plan or program sensorimotor commands necessary for directing movements that result in phonetically and prosodically normal speech” (Duffy, 2013).

A baby who does not coo or babble may display a symptom of apraxia of speech, per ASHA. A young child may only say a few consonant sounds, and an older child may have difficulty imitating speech. An adult also has thisdifficulty. Individuals with apraxia of speech know what words they want to say, but their brains have difficulty coordinating the muscle movements necessary to say all the sounds in the words. Thus, they may say something completely different or make up words (e.g., “bipem” or “chicken” for “kitchen”) according to an ASHA report.This situation can become quite frustrating for the person.

A person diagnosed with apraxia may also have aphasia, a condition caused by damage to the brain’s speech centers.This results in difficulty reading, witting, speaking, and understanding when others speak.

In some cases, people with acquired apraxia of speech recover some or all their speech abilities on their own. Children with developmental apraxia of speech will not outgrow the problem on their own. Speech-language therapy is often helpful for these children and for people with acquired apraxia who do not spontaneously recover all their speech abilities.

In severe cases, people with acquired or developmental apraxia of speech may need to use other ways to express themselves. These might include formal or informal sign language, a language notebook with pictures or written words, or an electronic communication device that writes and produces speech  (Binger et al, 2008).

Constructional apraxia:

Constructional apraxia is an inability to reproduce patterns or join component parts into a whole. This condition is assessed through observation of a patient completing activities such as drawing, copying, or building three-dimensional objects (Lezak, Howieson, &Loring, 2014). Impairments in processing spatial forms observed in constructional apraxia can occur in the absence of apraxia of singular motor movements.

Constructional apraxia can also be defined as the inability of patients to copy accurately drawings or three-dimensional constructions. It is a common disorder after right parietal stroke, often persisting after initial problems such as visuospatial neglect have resolved.

Recent studies suggest qualitatively different types of constructional apraxia determined by the location of brain insult. In general, patients with right hemisphere impairment make more coordinate type errors (e.g., distance and angular distortions).On the other hand, those with left hemispheric impairment tend to commit categorical errors (e.g., position exchanges and pattern reversals) (Laeng, 2008).

Conclusion:

In a nutshell, apraxia is not just a psychological disorder but is a serious mental condition which raises concerns for individuals as well as their families on medical grounds. It is a disease which refers to the inability to perform movements without the presence of any physical or motor disability in the peripheral areas of the body. This generally occurs when there is a lesion in the parietal cortex of the brain due to cell injury, trauma or electrolyte imbalance in the brain. As mentioned above, apraxia has many subtypes which are explained per the problem they highlight.

For instance, the most common type of apraxia is Ideomotor apraxia and can be described as the inability or difficulty to perform planned movements, the next type in limb-kinetic which refers to difficulty in motor functions, ideational apraxia which is inability to perform daily functions, speech apraxia which is also very common and refers to difficulty in formulating and speaking words even though the speech construction is complete on the level of the dominant cerebral cortex. Apraxia can also be classified as constructional which is the inability to draw objects and figures and oculomotor which as its name suggests is a lesion in the optic pathway followed by the oculomotor nerve and causes difficulty in completing eye movements. Per recent research and several clinical trials mentioned above, apraxia can be treated mostly with therapy depending on its type and severity. Various forms and subdivisions of physiotherapy have now been introduced in medical sciences which enable fast recovery and cure of several neurological and psychological disorders.

This involves a new format of speech therapy which runs along mechanical training to ensure motor function of the muscles which enable speech in the larynx, occupational therapy to overcome the psychological aspects of apraxia and lack of confidence in patients with apraxia and most importantly the relevant type of motor or physiotherapy in patients with motor function disabilities. Apraxia should be ruled out as a symptom to a secondary disease or a disease itself upon clinical assessment initially. It is treatable condition but can result to be fatal if not caught on time and managed with care. It is an ideal condition to illustrate the proverb “prevention is better than cure.”

References:

Heilman KM. Apraxia. In: Heilman KM, Valenstein E, editors. Apraxia. New York: Oxford University Press; 2008.

Anheim, Mathieu, et al. “Clinical and molecular findings of ataxia with oculomotor apraxia type 2 in 4 families.” Archives of neurology 65.7 (2008): 958-962.

Rothi, Leslie J. Gonzalez, and Kenneth M. Heilman. Apraxia: the neuropsychology of action. Psychology Press, 2014.

Vanbellingen, Tim, et al. “Comprehensive assessment of gesture production: a new test of upper limb apraxia (TULIA).” European Journal of Neurology 17.1 (2010): 59-66.

Ochipa C, Rothi LJ, Heilman KM. Conceptual apraxia in Alzheimer’s disease. Brain 2012; 115(Pt 4): 1061–71.

Fukutake T. (2013). “Apraxia of tool use: An autopsy case of biparietal infarction”. European Neurology. 49 (1): 45–52.

Hanna-Pladdy B, Rothi LJ (2010). “Ideational apraxia: Confusion that began with Liepmann.” Neuropsychological Rehabilitation. 11: 539–47.

Cooper RP (2008). “Tool use and related errors in ideational apraxia: The quantitative simulation of patient error profiles”. Cortex. 43 (3): 319–37

Unsworth, C.A. (2007). Cognitive and Perceptual Dysfunction. In S. B. O’Sullivan, & T. J. Schmitz (Eds.), Physical Rehabilitation (5th Ed.) (p.1182). Philadelphia: F.A. Davis Company.

Manuel, Aurelie L., et al. “Inter-and intrahemispheric dissociations in ideomotor apraxia: a large-scale lesion–symptom mapping study in subacute brain-damaged patients.” Cerebral Cortex (2012): bhs280.

Duffy, J. R. (2013). Motor speech disorders: Substrates, differential diagnosis, and management. St. Louis, MO: Elsevier.

Binger, C., Kent-Walsh, J., Del Campo,S., Hickman, S., Marquez, C., &Rivera, D. (2008, November).Teaching educators and parents tosupport language development in AAC. Paper presented at the annual ASHA Convention, Miami,FL.

Lezak, M. D., Howieson, D. B., &Loring, D. W. (2014). Neuropsychological Assessment (4th ed.). New York: Oxford University Press.

Laeng, B. (2008). Constructional apraxia after left or right unilateral stroke. Neuropsychologia, 44:1595–1606.