A. Waveforms for LPP at CPz for control and sleep restricted participants. Solid line indicates positive images, broken grey line indicates negative images, and light grey line indicates neutral images. Note the different pattern of the LPP in sleep restricted participants, where the LPP is larger for positive (relative to neutral) and similar to the negative (relative to neutral). B. Waveforms for LPP at CPz for control and sleep restricted participants. Solid lines indicate controls, and broken lines indicate sleep restricted participants. The red and navy lines are amplitudes to neutral stimuli, and the blue and green lines are amplitudes to positive stimuli. Note the different pattern of the LPP in sleep restricted participants, where the LPP is larger for positive (relative to neutral).