Motor activity is primarily controlled by the….
A. parietal lobe
B. temporal lobe
C. frontal lobe
D. occipital lobe
The correct answer and explanation is :
The correct answer is C. frontal lobe.
The motor activity of the body is primarily controlled by the frontal lobe of the brain, particularly the primary motor cortex, which is located in the precentral gyrus of the frontal lobe. The motor cortex is responsible for generating neural impulses that control the execution of voluntary muscle movements.
Here’s how the process works:
- Primary Motor Cortex: The primary motor cortex, located in the frontal lobe (specifically in the precentral gyrus), plays a key role in voluntary movement. Neurons in this area send signals to the muscles, controlling fine motor movements such as writing, speaking, and more complex coordinated actions.
- Motor Homunculus: Within the primary motor cortex, the layout of the neurons is organized in a way that is proportional to the amount of motor control required by each part of the body. This organization is known as the motor homunculus, where larger areas are dedicated to more intricate movements like those of the hands, face, and fingers.
- Premotor Cortex: The premotor cortex, also located in the frontal lobe, assists in planning and coordinating voluntary movements. It helps organize movements before they are executed by the primary motor cortex.
- Supplementary Motor Area (SMA): This area of the frontal lobe is involved in the coordination of complex movements and in motor planning. It helps organize and initiate sequential movements.
- Cerebellum and Basal Ganglia Support: Though motor activity is initiated by the frontal lobe, the cerebellum and basal ganglia play a supportive role. The cerebellum ensures that movements are smooth and coordinated, while the basal ganglia help refine movement and control the initiation and cessation of motor actions.
In summary, while several regions of the brain work together to control motor activity, the frontal lobe, with its motor cortex, is the primary control center for voluntary movements.