Which statement is FALSE?
a. The reticular formation is responsible for our different levels of arousal and consciousness.
b. The thalamus serves as a relay station for incoming sensory information.
c. The medulla is responsible for the initiation and execution of physical movements.
d. The cerebellum is concerned mainly with the coordination of physical movements.
The correct answer and explanation is:
The correct answer is c. The medulla is responsible for the initiation and execution of physical movements.
Explanation:
The medulla is part of the brainstem and is primarily involved in regulating vital functions such as heart rate, blood pressure, and respiration. It does not play a direct role in the initiation and execution of physical movements. The medulla is more concerned with autonomic functions necessary for survival, like breathing and heart rate control. The initiation and coordination of voluntary physical movements are more closely associated with the motor cortex in the cerebrum, as well as with structures like the basal ganglia and cerebellum.
Explanation of Other Statements:
- a. The reticular formation is responsible for our different levels of arousal and consciousness.
- This statement is true. The reticular formation, a network of neurons located in the brainstem, plays a crucial role in regulating the sleep-wake cycle, alertness, and overall consciousness. It helps control the transition between sleep and wakefulness and plays a role in maintaining arousal levels.
- b. The thalamus serves as a relay station for incoming sensory information.
- This statement is true. The thalamus acts as a relay station, processing and transmitting sensory signals (except for smell) to the appropriate regions of the cerebral cortex. It is a crucial hub in sensory perception and motor control.
- d. The cerebellum is concerned mainly with the coordination of physical movements.
- This statement is true. The cerebellum is located at the back of the brain and is primarily responsible for the coordination of voluntary movements. It helps in maintaining posture, balance, and fine motor control. The cerebellum also plays a role in motor learning and the timing of movements.
In summary, the medulla does not initiate and execute voluntary movements; that function is more associated with other areas of the brain like the motor cortex.