Oscillatory Control over Representational States in Working Memory

In the visual world, attention is guided by perceptual goals activated in visual working memory (VWM). However, planning multiple-task sequences also requires VWM to store representations for future goals. These future goals need to be prevented from interfering with the current perceptual task. Recent findings have implicated neural oscillations as a control mechanism serving the implementation and switching of different states of prioritization of VWM representations. We review recent evidence that posterior alpha-band oscillations underlie the flexible activation and deactivation of VWM representations and that frontal delta-to-theta-band oscillations play a role in the executive control of this process. That is, frontal delta-to-theta appears to orchestrate posterior alpha through long-range oscillatory networks to flexibly set up and change VWM states during multitask sequences. Neural oscillations serve important regulating functions in the interaction between working memory and sensory input in sequences of visual selection tasks.During multitask sequences, alpha (∼10 Hz) oscillations above visual cortex regulate which sensory working memory representation in early visual cortex is activated and, therefore, interacts with the current sensory input, and which information is (temporarily) deactivated, to prevent such interaction.Delta-to-theta (∼2–8 Hz) oscillations above frontal brain regions orchestrate alpha oscillations above visual cortex during both the initialization and switching of representational states in VWM when executing multitask sequences.