You could be in the category of a morning person or a night owl. However, if you are one of those innumerable people who has enrolled in a good foreign language school to learn a new language, it can help if you are an insomniac, according to a study conducted by Duolingo. The study concluded that if a person makes a regular practice of practicing the foreign language he or she is learning prior to going to bed at night, there is a greater likelihood of remembering it well.
To explore the subject even further, many studies have claimed that sleep has a positive influence on learning. In 2016, a study was conducted that investigated the relationship between sleep and repeated practice have on information retention in the long-run. It was particularly effective for getting familiar with the vocabulary of a foreign language. The study was conducted on 40 participants who practiced vocabulary on foreign languages, 50 percent of them learned in the evening and reviewed the lesson the next day morning. The other 50 percent did the reverse. They learned the lesson in the morning and reviewed the lesson in the same evening. Seven days later and then 6 months later, the retention of these participants were assessed by the researchers. It was discovered by the researchers that the participants who slept between learning and reviewing the lessons enjoyed retention for a longer time period.
But practicing a foreign language before going to sleep at night is not the only way. You should make a daily habit of learning the new language and do it consistently.