Changes

The interplay of two significant processes regulates the sleep-wake system.  

The interplay of two significant processes regulates the sleep-wake system.  

a) Process S is the homeostatic drive for sleep. It is regulated by the neurons found in the preoptic area of the hypothalamus of the brain. These neurons contain molecules that inhibit neuronal communication and turn off the arousal systems during sleep.  

'''a) Process S''' is the homeostatic drive for sleep. It is regulated by the neurons found in the preoptic area of the hypothalamus of the brain. These neurons contain molecules that inhibit neuronal communication and turn off the arousal systems during sleep.  

b) Process C promotes wakefulness and alertness. The circadian system regulates it. Wakefulness is generated by an ascending arousal system from the brainstem. This activates forebrain structures by transmitting sensory information to the cerebral cortex and activating the nerve cells to interpret and analyze the sensory inputs.  

'''b) Process C''' promotes wakefulness and alertness. The circadian system regulates it. Wakefulness is generated by an ascending arousal system from the brainstem. This activates forebrain structures by transmitting sensory information to the cerebral cortex and activating the nerve cells to interpret and analyze the sensory inputs.  

Through the synchronization of the circadian system, process C assists in keeping sleep-wakefulness cycles coordinated with environmental light-dark cycles.  

Through the synchronization of the circadian system, process C assists in keeping sleep-wakefulness cycles coordinated with environmental light-dark cycles.