Alpha waves are most prominent during which condition?

Alpha waves are most prominent during which condition?

• A. Deep sleep
• B. REM sleep
• C. Intense concentration
• D. Relaxed wakefulness with eyes closed

Answer: (D)

Alpha waves reflect a relaxed, awake brain state with eyes closed. They appear as a regular 8–12 Hz rhythm, most pronounced over the back of the head (occipital region) when a person is quietly resting and not processing sensory input. This state is known as the posterior dominant rhythm, and it diminishes when you open your eyes or concentrate, a phenomenon called alpha blocking. In deep sleep the EEG shows slow, high-amplitude delta waves, not alpha. REM sleep resembles wakefulness in some ways with low-amplitude, mixed-frequency activity and characteristic sawtooth patterns, but not the clear alpha rhythm. Intense concentration typically produces faster beta activity and desynchronization, which lowers alpha. So relaxed wakefulness with eyes closed best explains the prominent alpha activity.

Alpha waves reflect a relaxed, awake brain state with eyes closed. They appear as a regular 8–12 Hz rhythm, most pronounced over the back of the head (occipital region) when a person is quietly resting and not processing sensory input. This state is known as the posterior dominant rhythm, and it diminishes when you open your eyes or concentrate, a phenomenon called alpha blocking.

In deep sleep the EEG shows slow, high-amplitude delta waves, not alpha. REM sleep resembles wakefulness in some ways with low-amplitude, mixed-frequency activity and characteristic sawtooth patterns, but not the clear alpha rhythm. Intense concentration typically produces faster beta activity and desynchronization, which lowers alpha. So relaxed wakefulness with eyes closed best explains the prominent alpha activity.