Cover legend: Slow activity transients (SATs) in infant rat visual cortex. SATs are the cortical activity induced in visual cortex by phase 3 retinal waves. Wide-band depth EEG recordings from layer 4 of a P10 rat show prominent infra-slow potentials containing beta-band (15-30 Hz) oscillations. A 120 s trace containing two SATs is shown in green. The background image is a Morlet-wavelet transform of the signal between 0.5 and 50 Hz (log scale) plotted using a black–red–yellow–white (low to high) color translation. This analysis shows the frequencies associated with neural events, including the prominent beta-band oscillations (red color surrounded by the green line) that exclusively occur during SATs. For exact x and y axes and for more information, see the article by Colonnese and Khazipov in this issue (pages 4325–4337).