According to the previous researches, insomniacs show cortical hyperarousal such as high proportion of high frequency EEG around sleep onset or NREM sleep. Also, Insomniacs shows cortical hyperarousal while they are waking, so this characteristic is known to be 24 hours hyperarousal. However, there is few research that how cortical hyperarousal is related to the insomniacs’ symptoms. This research investigates the relationship of waking EEG(High beta 4) which indicates cortical hyperarousal and insomnia symptom focused on sleep latency. In current study's result, Sleep onset latency showed significant positive correlation with Beta 4 from Occipital, Frontal, Parietal, Central, Left Temporal area. The result shows the possibility that insomniacs cannot reduce their waking High Beta, which means hyperarousal, so, their sleep onset latency increases when they try to fall asleep.

The Relationship Between Cortical Arousal and Sleep Latency in Primary Insomniacs