Kam, J. W. Y., Dao, E., Farley, J., Fitzpatrick, K., Smallwood, J., Schooler, J. W., et al. (2011). Slow fluctuations in attentional control of sensory cortex. Journal of Cognitive Neuroscience, 23(2), 460-470. doi:10.1162/jocn.2010.21443.