Lernposter über Schlafphasen

Educational poster titled 'Sleep Stages & Cycles'. Shows a hypnogram/cycle graph across the night with NREM stages 1-2-3 and REM (90-120 min cycles). Illustrations of brain waves: beta/alpha for awake, theta for N1, sleep spindles for N2, delta for N3, and beta-like for REM. Pie chart showing ~75% NREM and ~25% REM. Icons for eye movements, muscle activity, heart rate changes. Colourful study guide infographic with blue tones for sleep stages.