Listening to music can help with sleep
For teens, does wearing headphones with music playing while sleeping affect the quality of their sleep? Also, does listening to music while studying impact the quality of studying? --
The effect of music on sleep has been studied several times, but most studies have looked at classical or soothing music. In most of the trials I read, music at bedtime improved the quality and duration of sleep. If your teens are anything like my teens were, however, classical or soft music is unlikely to be their choice. Also, the trials did not examine the effect of headphones, which may alter the different head positions people use when falling asleep.
As far as the studying question goes, there clearly are differences among people. However, in several studies that included school-aged children, adolescents and young adults, studying in silence led to better reading comprehension compared with a noisy room, highly arousing music (such as heavy metal) or less arousing music (pop vocal music).
However, those listening to "low arousal" music had better scores than those listening to noise. People listening to highly arousing music scored worst in reading comprehension and reaction time.
Many people feel they study best with music. Some researchers have found that music that is well-known and doesn't demand much attention is least likely to interfere with learning.
In giving good advice about drinking alcohol, you never mention it causing damaged brain cells. A neurologist once told me that a brain scan of an alcoholic patient showed the ravages of alcohol. He granted that even much less drinking would cause some damage. When I asked him about the two martinis he had routinely before dinner, he shrugged. He died at 73, probably due to his genes. I wouldn't try to connect alcohol to cause of death, only the sharpness of one's brain till the end.
A very recent study just looked at the effect of moderate drinking on brain outcomes. They looked at changes on the brain scans in specific areas of the brain. They found that drinking even moderate amounts -eight standard drinks per week -- increased the likelihood of brain atrophy (in the U.S., a "standard drink" is 14 grams of alcohol, about what is in 12 ounces of most beer, a 5-ounce glass of wine or a standard "shot" of distilled spirits).
People who drank less alcohol had a nonsignificant amount of atrophy (but did not have any degree of protection). The study had flaws, relying on self-reporting, and had a relatively small sample group; however, the results certainly are plausible.
In addition, the more alcohol people drank, the more likely they were to have rapid decline in their cognitive ability.
There were fewer women in the study, and researchers could not make meaningful comments about men versus women; however, because of men and women's average size, as well as the relative size and activity of the liver, it would be expected that women might have a greater effect for the same amount of alcohol.
Based on this study, I agree with the neurologist you spoke to. Even moderate amounts of alcohol may adversely affect the brain as we age. This new information should be considered in future guidelines on alcohol use.