Controlled and automated processes

Humans have two different mechanisms available for executing voluntary movements: Feedback movements are characterised by maximum control and are normally used for unlearned movements. On the other hand, automatic feed-forward movements are characterised by maximum efficiency and are used for learned movements.

Glossary

Volitional movement → Intentional, i.e. deliberately controlled movements that are consciously controlled but can also be executed automatically.

closed loop movements → Consciously controlled movements under proprioceptive or visual detailed control.

open loop movements → Automated movements that had to be learned beforehand and are already fully planned in advance before execution.

Effer copy → A copy of the desired movement result for automated open-loop movements. The efference copy is then used to check the success of the movement.

Content

Basically, the brain works on two different levels: Consciousness and Subconsciousness. Even though we feel that our consciousness actually controls our being, the processing capacity of the subconscious mind is much greater. Much of the information and stimuli perceived unconsciously cannot even enter our consciousness because this information is filtered through the thalamus. Every second (!), about 10 million bits of information enter our brain, and the conscious mind would be completely overwhelmed by processing this amount of information. It is assumed that only about 1% of the information in the brain can be processed consciously. Of course, this also has consequences for the organisation before learning processes, where a lot of information has to be processed (see alsoimplicit learning ). But the decision-making processes are also mostly unconscious, without us realising it. Conscious thinking is organised serially, so that information must be processed one after the other. In contrast, unconscious thinking is organised in parallel and therefore can process an extremely large amount of information simultaneously. Our brains face a similar resource problem when planning and executing movements. The serious difference between consciously controlled and unconsciously automated movements is described below.

Control of arbitrary movements

Humans have two fundamentally different mechanisms at their disposal for executing voluntary movements. These two movement mechanisms differ in many aspects. "Closed loop" controlled movements are characterised by maximum control and are normally used for unlearned movements. On the other hand, automated "open-loop" movements are characterised by maximum efficiency and are used for learned movements.

Controlled movements

In the case of "closed-loop" controlled movements, deviations detected during execution are constantly readjusted with the help of sensory or visual feedback. For these movements, there is a more precise idea of the desired form before the execution begins, but there is no plan for a holistic basic movement pattern. This may not have been learned yet - for example, when trying to play a new instrument or learning to write. One starts performing the movement slowly and then, depending on the feedback, continuously adjusts the movement during the execution. As a result, the muscles are constantly being activated and deactivated. Since the move has already been controlled during execution, there is no subsequent control after the move has been completed, as the result of the move has normally been obtained in the best possible way.

Movement is controlled during execution and deviations are corrected immediately.

only very slow movements are possible
conscious control of movements requires a lot of attention.
Closed-loop motions are normally used when the motion has not yet been learned and therefore needs to be controlled in detail or for extraordinary spatial precision requirements. However, because of the relatively slow reaction time (about 250 ms for a conscious motor response to a stimulus) and the inertia of the eye tracking movement, such a movement must proceed at a very slow pace. An example of this is drawing precise lines by model, where a certain shape is drawn with slow movements and deviations can be corrected immediately. It takes about 1-2 seconds to accurately calligraph a letter according to the pattern, while it takes only 200ms to write a letter normally.

Automatic movements

The execution of automatic "open-loop" movements largely escapes conscious control of the movements. An example of this is speed writing, where a spelling mistake is only discovered after the letter or even the word has been written. Automatic movements underlie all our learned voluntary movements (such as grasping, catching). The degree of automation can even be used as a direct measure of performance in high-performance sports.

In the case of automated movements, a complete motor plan for implementation is already designed before execution begins. Through movement patterns learned and stored in motor memory, a holistic movement sequence is planned. A copy of this movement sequence and the desired effect is then made and stored in the brain (effect copy), which is later used to check the result of the movement. The decisive point of this control strategy is that no feedback-controlled movement corrections are made during movement execution, as these corrections would hinder the smooth and fast movement process. Therefore, these movements can be very complex and at the same time extremely fast. At the same time, the learned automatic movements are very effective - all the muscles involved ideally work in perfect harmony.

Properties of automatic movements:

the result of the movement is predicted
no information is processed during movement
the result of the move is compared to the prediction
Deviations are taken into account in the next move
feed-forward movements can be executed with any degree of complexity

Automated movements must first be learned and optimized (seethe Fitt learning model ). In principle, the learning of automatic movements corresponds to the continuous and repeated search for a solution for a specific task. Already during learning, control over movement execution is continuously reduced. Instead, a different learning mechanism is used. After the move is completed, a follow-up check is performed, and the deviations from the planned result of the move are used for the corrected planning of the next move. This mechanism leads to subsequent learning of specific executions of this movement.

What does this mean for my teaching practice?

Automated movements, such as routine handwriting, self-organize and are no longer controlled during execution. Only when writing is automated is working memory not loaded and available for other tasks such as text comprehension or grammar.

Reflection question

How can the control of automated movements still be guaranteed? For example, even fast handwriting remains legible.

Quiz

1) Controlled closed loop movements

A) are completely planned in advance
B) are executed quickly
C) are subject to sensory and visual control

2) Automated movements

A) are beyond conscious control
B) can still be controlled during execution

Answers

1️⃣ → C) are subject to sensory and visual control
2️⃣ → A) are beyond conscious control