Praxias
When we speak about praxias, we normally refer to the neurological process that allows us to organize, plan and perform motions and skills of all types in an efficient manner, from a lower to a greater difficulty, that are performed to reach an objective or to accomplish something. Normally they will be previously learned movements or actions that are performed when faced with a specific stimulus.
It will probably be easier to understand what exactly is a praxia if we give some examples. In this way, some of the more common praxias are the movement of a key when entering a lock, the motion we make when brushing our teeth, the motions we make when grabbing a spoon and bringing it to our mouth, among many others.
As a result, the majority of any actions performed by individuals are praxias. And, as expected for voluntary ideomotor tasks, the pyramidal tracts (responsible for motor activities started unconsciously), the extrapyramidal system (responsible for the control and adjustment of automatic and unconscious movements) and the premotor cortex, are the main mechanisms that have an influence on praxias.
How do we use praxias?
As we explained in the previous section, praxias are learned, coordinated movements that allow us to reach a specific objective. Moreover, these movements will be performed automatically and, as a result, they are performed completely unconsciously. Obviously, praxias are very useful in our daily lives. The use of automated movements according to a stimulus or object allows us to develop in a more efficient manner. And this is exactly what allows us to perform multiple activities quickly, without even “thinking about it”, as some might say. Imagine how you life would be, your daily interactions with the rest of the world, if every one of your movements had to be performed in a completely conscious way, monitoring and controlling each step of that movement or task.
Moreover, praxias have one more advantage. By allowing us to imitate actions or movements, they also allow us to learn from the actions or movements of others. And, as many of you know, this is one of the main ways in which human beings learn and develop throughout their lifetimes. Summarizing, praxias are fundamental in enabling us to interact with the world that surrounds us in a more efficient manner.
Main Types of Praxias
In general, there are five main types of praxias: ideomotor, ideatory, constructional, facial and dressing praxias. Next, we will define each of these types in more detail:
Ideomotor: this type of praxia defines the intentional performance of a gesture or simple movement. Normally, those gestures or movements will be performed in response to an order, stimulus or to imitate a movement like putting a scared face or imitating how to use a key.
Ideatory: these praxias are related with the capacity to start a sequence of gestures in order to use real-world objects. For example, grabbing a jar and filling a glass with water or removing a screw with a screwdriver.
Constructional: is the capacity to plan and perform the movements needed to copy a drawing, model an object, complete a puzzle or follow a recipe.
Facial: they define the voluntary performance of movements or gestures with different parts of the face, like the lips, eyes, tongue, etc.
Dressing: although it is not a special “type” because it could be included with other ideatory praxias, it is normally given more importance when dealing with neurological patients. Normally understood as knowing where each garment goes and knowing how to dress oneself.
Exercises to Stimulate Praxias
As we have seen in previous sections, praxias can involve both motor and cognitive functions. This means that a multidisciplinary approach, once more, will be very beneficial for those patients that need to use exercises to stimulate praxias. In other words, the collaborative work among speech and language pathologists, neuropsychologists, occupational therapists and physiotherapists will be key to obtain the best possible outcomes.
As a result, there are multiple ways to stimulate praxias from both a physical and cognitive perspective. When we look at physical exercises, we see that showing patients a spoon and having them use it to bring soup towards their mouth is a good way to train ideomotor praxias, for example. As a result, Rehametrics has several exercises that use real-world environments where patients will have to use different types of objects to perform movements or gestures. Some examples are the exercises called Bimanual Coordination, Simultaneous Coordination or Elbow Flexo-extension. For cognitive exercises, we find different types of tasks called Kitchen or Closet, among others.
Patients with Apraxia
Praxias collaborate very closely with the other cognitive functions so as a result, when a neurological injury takes place, they can also be affected. If this occurs, we would be facing an apraxia. Apraxias represent the difficulty or impossibility to perform correctly those movements learned before the injury or neurological condition took place. Generally speaking, an apraxia can occur when an injury takes place that affects the prefrontal cortex, the primary or secondary motor cortex, the cerebellum or the basal ganglia and the posterior brain (formed by the temporal, parietal and occipital lobes).
The main clinical symptoms associated with that condition are the inability to perform a movement in response to an object, the inability to manipulate an object correctly or to imitate a movement adequately. As a result, an individual that suffers from an apraxia will have some of the capabilities mentioned above affected. For example, a person suffering from an ideomotor apraxia will be unable to put an idea into practice. This could mean that this person would could tie his or her shoelaces (which is an automatic action) but will be unable to use a TV remote control correctly (because he or she will not know what that object is used for).
