Which type of brain wave is associated with drowsiness or relaxation?

• A. Delta waves
• B. Beta waves
• C. Alpha waves
• D. Theta waves

Answer: (C)

The association of alpha waves with drowsiness or relaxation arises from their specific characteristics in the context of brain activity. Alpha waves typically have a frequency of 8 to 12 Hz and are most prominent during states of calmness and relaxation, especially when the eyes are closed but the individual is not in deep sleep. This brain wave activity indicates a transition phase from wakefulness to the early stages of sleep, commonly observed during meditation or light relaxation.

In contrast, delta waves are associated with deep sleep and have a much lower frequency, while beta waves, characterized by a higher frequency, are indicative of active thinking and alertness. Theta waves, which are slower than alpha waves, are typically linked to lighter stages of sleep or deep relaxation but do not fully encapsulate the serene state that alpha waves represent during wakefulness. Thus, alpha waves are the key indicators of drowsiness or relaxation, making them the correct choice in this scenario.