Paradoxical insomnia, previously known as sleep state misperception, occurs when someone consistently underestimates how much sleep they get. Someone with paradoxical insomnia may believe that they only got a few hours of sleep when in reality they slept for an adequate length of time. Someone with paradoxical insomnia may believe they are suffering from insomnia but typically doesn’t show the daytime symptoms inherent to insomnia, such as fatigue or delayed reaction time. It’s unclear what causes paradoxical insomnia, but it can be very distressing to those who have it because they feel their sleep challenges are dismissed or ignored by clinicians. Fortunately, it can usually be treated effectively, often with cognitive behavioral therapy for insomnia (CBT-I).