Final answer:
Delta waves, with their low frequency and high amplitude, are seen in deep sleep or general anesthesia.
Step-by-step explanation:
In deep sleep or general anesthesia, the EEG waveforms seen are characterized by low frequency, high amplitude delta waves. These delta waves, with a frequency of less than 3 Hz, have the lowest frequency and highest amplitude among all brain wave patterns. During this stage, an individual's heart rate and respiration slow dramatically, making it difficult to wake someone from sleep.