Apraxia: causes, symptoms and treatment

There are multiple causes that can lead to brain injury. Similarly, the repercussions of an injury to the nervous system can produce a wide variety of symptoms depending on the area affected and the type of damage that has occurred.

Examples of this may be speech comprehension problems, perception of stimuli through the senses or problems related to the motor system. Within this last type of problem can be found the difficulty or loss of capacity at the time of perform sequential movements, which are used on a daily basis when performing very different Actions. We are talking about apraxias.

A little preamble: what kind of movements do we make?

To understand what an apraxia is, it is necessary to take into account the great diversity of movements that we do. Whether they are volunteers or not, the capacity of movement has allowed the human being to develop as a species and be able to carry out highly complex actions.

Some of the main movements that the human being performs are the following.

1. Reflexes

These types of movements tend to be intense reactions of little complexity and duration., generally due to the activation of a bundle of specific nerve fibers. These are small movements made involuntarily.

2. Voluntary movements

Voluntary movements are those that we carry out with a specific goal, at a conscious level and that at least originally need the attention of the individual to be able to perform correctly. With enough practice, they can become automated.

3. Automatic movements

This time a behavior is carried out voluntarily, but it is automatedIn other words, conscious attention to the sequence of actions is not required to carry it out beyond choosing the starting and / or ending moment. These are sequences of actions internalized thanks to practice and the habituation of the person to perform them, such as For example, the set of actions that we carry out to have a soup, ride a bike, drive, sit or even talk or to walk. It is in these types of movements that apraxias appear.

Describing the concept of apraxia

Once the brief explanation above is taken into account, it is easier to explain the concept of apraxia. It is understood as such cessation or high difficulty of the ability to perform purposeful movements that require sequencing and coordinating movements, making it impossible to perform certain automatic movements.

This alteration is generally due to a brain injury, maintaining the subject who suffers the ability to understand the action that is asks you to do, being the task easy to perform or being this already known by the individual and maintaining muscular functioning Right. Generally, the individual does not present anosognosia, so he is fully aware of his deficit.

Most known types of apraxia

As we have mentioned, apraxia implies an inability to perform sequences of coordinated movements in a sequential and orderly manner.

However, nor there is only one typology of this problem, with a large number of kinds of apraxia. Some of the main ones are reflected below.

1. Ideational apraxia

In this type of apraxia, subjects have a difficulty not only in carrying out coordinated tasks, but also in imagining them, in many cases not being able to imagine the correct sequencing necessary to carry out a specific behavior. However, the individual actions that make up the sequence can be done correctly.

It is also considered as ideational apraxia (although in this case it is also called conceptual) the difficulty to use objects due to the same causes, that is, ignorance of the sequence of actions necessary to use, for example, a hair comb. It is common in neurodegenerative diseases such as dementia due to Alzheimer's disease or Parkinson's, as well as in lesions of the dominant hemisphere and the corpus callosum.

2. Ideomotor apraxia

This type of apraxia is the most common in clinical practice. On this occasion, the subjects can correctly imagine the sequence of actions necessary to carry out a certain behavior, although they are not able to carry it out physically.

In ideomotor apraxia the deficit is found in a difficulty in planning the movement. Within this typology, different subtypes could be found, such as orofacial apraxia, of the speech, limbs and axial (the axis of the body, which affect actions such as sitting and position). They are frequent in bilateral lesions and cortico-basal degenerations, being generally affected both sides of the body.

3. Constructive apraxia

Regarding constructive apraxia, is based on difficulty in construction or drawing due to difficulties in spatial perception and eye-hand coordination. Thus, there is no correct association between the visually perceived image and the movements necessary to carry out the elaboration. Some subjects with this type of problem are unable to recognize the differences between the stimulus given to them asks to copy and its elaboration, getting to discuss if the problem is of movement or of integration between information.

Also called visuoconstructive deficit, this type of apraxia is used as an indicator of cognitive deterioration due to its early appearance in Alzheimer's patients. It usually occurs in patients with lesions in the right hemisphere, but a large number of cases have been observed in which the damaged hemisphere is the left. The lesion is usually located in the parieto-occipital region, which is coherent taking into account the lack of coordination between vision (which is located mainly in the occipital lobe) and movement (present in the parietal).

Possible causes

Apraxia, as a result of brain injury, can have a wide variety of causes. Although the list of possible causes is much more extensive, some of them may be the following.

Cardiovascular accidents

Whether it is a hemorrhage or if we are talking about a stroke, cardiovascular accidents usually cause the death of part of the brain, being the most common cause of apraxia and other disorders related to brain injury.

Head injuries

A contusion that affects the brain can cause serious damage to the brain, which may or may not be reversible.. Depending on the area damaged by the blow, or the possible kickback (that is, the blow produced in the side opposite the injury due to rebounding against the skull), apraxia may appear with ease.

Brain tumors

The presence of a strange and growing mass in the brain causes damage to various areas of the brain, both due to the tumor itself and to the pressure exerted on the brain against the skull. If these damages occur in the areas responsible for the motor system or in areas of association that integrate the coordination of movements, the appearance of apraxia is greatly facilitated.

Neurodegenerative disease

Disorders that present with a progressive deterioration of the nervous system are closely linked to the presence of apraxias. In fact, one of the characteristics of cortical dementias is the presence of aphasic-apraxo-agnosic syndrome, which includes the progressive appearance of speech problems, movement sequencing, and perceptual and intellectual abilities.

Treatment

Being generally the product of brain injuries, apraxias are problems whose form of treatment will vary greatly depending on their cause. Although difficult to recover and although in some cases sequelae may remain, the type of treatment performed in general tends to use therapy on a physical level, and rehabilitation or compensation of functions losses.

Bibliographic references:

• Ardila, A. (2015). Kinetic, ideomotor, ideational and conceptual apraxia. Journal of Neuropsychology, Neuropsychiatry and Neurosciences, Vol.15, Nº1, pp. 119-139

• Bradley, W.G.; Daroff, R.B. et al. (2004) Clinical Neurology: diagnosis and treatment. Vol I. Fourth edition. Page 127-133.

• Garcia, R. and Perea, M.V. (2015). Constructive and dressing apraxia. Journal of Neuropsychology, Neuropsychiatry and Neurosciences, 15, 1, 159-174.

• Greene, J.D.W. (2005). Apraxia, agnosias and higher visual function abnormalities. J Neurol Neurosurg Psychiatry; 76: v25-v34.