Question

get your zzzs
if youve ever had a sleepless night, you know that a lack of sleep can make you feel sluggish. yet failing to get a good nights sleep can also have more serious consequences. sleep plays an important role in the process of learning new information. a lack of sleep reduces a persons ability to pay attention and concentrate, which makes learning more difficult. in addition, sleep is necessary for remembering information. in 2009, researchers discovered that brain patterns called sharp wave - ripple complexes consolidate memories - that is, fix them in the brain - and transfer them to long - term storage. these brain waves happen most often during the deepest phases of sleep. thus, you may have a hard time remembering what you learned during the day if you dont get enough sleep.
what is the main, or central, idea of the passage?
sharp wave - ripple complexes, which often occur during deep sleep, are important for long - term storage of memories.
failing to get enough sleep may cause a person to feel sluggish.
without enough sleep, a person may have a hard time learning and remembering information.

Explanation:

The passage starts by stating the general feeling of sluggishness from lack of sleep, then focuses on how lack of sleep affects learning (reduces attention and concentration) and memory (due to the role of sharp - wave ripple complexes during deep sleep). The main idea encompasses both learning and memory aspects related to lack of sleep.

Answer:

Without enough sleep, a person may have a hard time learning and remembering information.