Automatic movements: a definition
Automatic movements are an essential part of our daily lives, often performed without our paying any attention. They are regulated by specific neuronal circuits, in particular the extrapyramidal and cerebellar systems.
Automatic movements are motor actions that do not require conscious attention and are often learned and repeated. They are in contrast to voluntary movements, which require conscious planning and control.
The role of the extrapyramidal and cerebellar systems
- The extrapyramidal system: This system is mainly involved in controlling posture, muscle tone and automatic movements. It plays a crucial role in the fluidity and coordination of movements. The basal ganglia, an important part of this system, are involved in programming and initiating movements.
- Cerebellum: The cerebellum is essential for movement coordination, balance and posture maintenance. It receives information about movements in progress and compares it with an internal representation of the desired movement, enabling movements to be adjusted in real time.
Examples of automatic movements
- Walking: A complex movement involving numerous joints and muscles, coordinated automatically.
- Eye movements: Eye movements to follow an object or focus on a point are automatic.
- Everyday gestures: Eating, drinking and dressing are actions that become automatic with practice.
- Reflexes: Reflexes such as the patellar reflex are automatic motor responses to sensory stimulation.
Automatic movement disorders
Dysfunctions in the extrapyramidal or cerebellar systems can lead to automatic movement disorders. These disorders may manifest as :
- Tremor: Involuntary oscillations of a part of the body.
- Rigidity: Increased muscle tone, making movement more difficult.
- Akinesia: Decreased range and speed of movement.
- Dysmetria: Difficulty assessing distances and adjusting the strength of movements.
- Balance problems: Difficulty maintaining a stable position.
Associated diseases
Many neurological diseases can affect automatic movements, including :
- Parkinson's disease: characterised by tremors, rigidity and akinesia.
- Multisystem atrophy: a degenerative disease that affects several systems, including the nervous system.
- Stroke: can lead to motor disorders depending on the area of the brain affected.
- Brain tumours: can compress the brain structures involved in controlling movement.
To sum up
Automatic movements are essential to our daily lives and are regulated by complex neural circuits. The extrapyramidal and cerebellar systems play a crucial role in the coordination and fluidity of these movements. Disorders of these systems can lead to significant difficulties in daily life.
Go further