Repetition suppression, the phenomenon that the second presentation of a stimulus attenuates neural activity, is typically viewed as an automatic consequence of repeated stimulus presentation. However, a recent neuroimaging study has suggested that repetition suppression may be driven by top-down expectations. Here we examined whether and when repetition suppression can be modulated by top-down expectation. Participants listened to auditory stimuli in blocks where tone repetitions were either expected or unexpected, while we recorded ongoing neural activity using magnetoencephalography. We found robust repetition suppression in the auditory cortex for repeated tones. Interestingly, this reduction was significantly larger for expected than unexpected repetitions, both in terms of evoked activity and gamma-band synchrony. These findings indicate a role of top-down expectation in generating repetition suppression and are in line with predictive coding models of perception, in which the difference between expected and actual input is propagated from lower to higher cortical areas.

Our perception is facilitated if we know where and when a sensory stimulus will occur. This phenomenon is accounted for by spatial and temporal orienting of attention. Whereas spatial orienting of attention has repeatedly been shown to involve spatially specific modulations of ongoing oscillations within sensory cortex, it is not clear to what extent anticipatory modulations of ongoing oscillations are involved in temporal orienting of attention. To address this, we recorded magnetoencephalography while human participants performed a tactile discrimination task. We cued participants to the left or the right hand, after which a tactile stimulus was presented at one of several fixed temporal delays. We thus assessed whether and how ongoing sensorimotor oscillations are modulated during tactile anticipation. We provide evidence for three phenomena. First, orienting to an upcoming tactile event involves a spatially specific contralateral suppression of alpha- and beta-band oscillations within sensorimotor cortex. Second, this modulation is deployed with temporal specificity, and this is more pronounced for beta-band compared with alpha-band oscillations. Third, the contralateral suppression of beta-band oscillations is associated with faster responses to subsequently presented tactile stimuli. Control measures showed that these results cannot be explained by motor planning or execution. We conclude that the modulation of ongoing oscillations within sensory cortex reflects a unifying mechanism underlying both spatial and temporal orienting of attention.

Flexible behavior requires guidance not only by sensations that are available immediately but also by relevant mental contents carried forward through working memory. Therefore, selective-attention functions that modulate the contents of working memory to guide behavior (inside-out) are just as important as those operating on sensory signals to generate internal contents (outside-in). We review the burgeoning literature on selective attention in the inside-out direction and underscore its functional, flexible, and future-focused nature. We discuss in turn the purpose (why), targets (what), sources (when), and mechanisms (how) of selective attention inside working memory, using visual working memory as a model. We show how the study of internal selective attention brings new insights concerning the core cognitive processes of attention and working memory and how considering selective attention and working memory together paves the way for a rich and integrated understanding of how mind serves behavior.

Frequency-specific patterns of neural activity are increasingly interpreted as transient bursts of isolated events rather than as rhythmically sustained oscillations. This has potentially far-reaching implications for theories of how such oscillations originate and how they shape neural computations. As this debate unfolds, we explore alternative interpretations and ask how best to distinguish between them.