Ah ha! #49 will find.
Figure 2. Cartoon of Large and Jones’s  theory of oscillatory attention (based on ). The ‘hills’ at the bottom represent pulses of attentional resource concen- tration, which are distributed in time according to a phase oscillator, whose period and phase can become entrained to rhythmical external stimuli (represented by vertical black bars). When the attentional oscillator is not entrained, attentional pulses are broad (large period), representing a relatively temporally unfocused state. They become narrower (more focused in time) when the oscillator is entrained, and drift again when the external stimuli cease. Performance is best when target stimuli occur at expected times (peaks of the attentional pulses).
49 Large, E.W. and Jones, M.R. (1999) The dynamics of attending: how people track time-varying events. Psychol. Rev. 106, 119–159
50 Barnes, R. and Jones, M.R. (2000) Expectancy, attention and time. Cogn. Psychol. 41, 254–311