The lowest level of the motor control hierarchy is the __________.

• A. projection level
• B. segmental level
• C. cerebellar level
• D. precommand level

Answer: (B)

Verified step by step guidance

1. Understand the motor control hierarchy: The motor control system is organized into different levels, each responsible for specific functions. These levels include the segmental level, projection level, and precommand level.
2. Define the segmental level: The segmental level is the lowest level of motor control. It involves reflexes and automatic movements controlled by the spinal cord circuits. This level is responsible for basic motor patterns such as walking and withdrawal reflexes.
3. Define the projection level: The projection level is the middle level of motor control. It includes the motor cortex and brainstem nuclei, which send signals to the spinal cord to control voluntary movements.
4. Define the precommand level: The precommand level is the highest level of motor control. It involves the cerebellum and basal nuclei, which plan and coordinate movements before they are executed.
5. Compare the levels: Based on the definitions, the segmental level is the lowest level of the motor control hierarchy, as it handles basic reflexes and automatic movements without higher-level processing.