Visual working memory, which can only hold three of four objects at a time, is thought to be based on synchronized brain activity across a network of brain regions. Now a new study has allowed us to get a better picture of how exactly that works. Both the maintenance and the contents of working memory were connected to brief synchronizations of neural activity in alpha, beta and gamma brainwaves across frontoparietal regions that underlie executive and attentional functions and visual areas in the occipital lobe. Most interestingly, individual VWM capacity could be predicted by synchrony in a network centered on the intraparietal sulcus.
Human working memory is based on dynamic interaction networks in the brain
 Neuronal synchrony reveals working memory networks and predicts individual memory capacity. Proceedings of the National Academy of Sciences. 107(16), 7580 - 7585.(2010).