According to a recent study, sleep spindles, which are short spikes in brain activity that happen during one sleep phase and are recorded by the EEG, may control anxiety in persons with post-traumatic stress disorder (PTSD).
Related information
If this topic is personally relevant, the general page on Trauma and PTSD may be a helpful starting point. Trauma-related difficulties can also overlap with anxiety and depression.
If symptoms are persistent, severe, or affecting daily life, it can be helpful to speak with a qualified mental health professional.