What is the frequency range of alpha waves during early sleep? 14-30Hz 4-7Hz 1-3Hz 8-13Hz

The correct answer is **8-13Hz**. Here's why:* **Alpha waves** are a type of brainwave associated with a relaxed, awake state. They are typically present when someone is closing their eyes and resting.* **During early sleep**, the brain transitions from alpha waves to **theta waves**, which have a frequency range of **4-7Hz**. * **Delta waves** (1-3Hz) are associated with deep sleep.Therefore, the frequency range of alpha waves is not relevant to early sleep.