Even the strongest among us can find the first 15 minutes after waking up difficult.This is due to the fact that your brain isn't fully functional yet. This is known as sleep inertia. When you first wake up, you may experience sleep inertia, which occurs because a portion of your brain is still asleep. Forced desynchrony experiments have revealed that sleep inertia has a distinct impact on cognition compared to homeostatic and circadian drives and that sleep inertia is greatest during biological night awakenings. Insomniacs do not believe they are getting enough sleep at night.They may struggle to fall asleep or wake up repeatedly throughout the night or early in the morning.Insomnia becomes a problem when it interferes with your daily activities.Stress, an irregular sleep pattern, poor sleeping habits, mental health disorders such as anxiety and depression, physical ailments and pain, drugs, neurological abnormalities, and specialized sleep disorders are all common causes of insomnia.