![]() ![]() ![]() In situations where the ongoing spiking of a large population of neurons is correlated, this is problematic ( Averbeck et al., 2006). To successfully process information about a stimulus, the brain must be capable of elevating the signal of said stimulus above the noise generated by ongoing neuronal activity ( Harris and Thiele, 2011). idling inhibition ), we provide empirical evidence in support of a new perspective: alpha/beta power decreases are a proxy for information processing. ![]() While numerous domain-general processes have already been ascribed to alpha/beta oscillations (e.g. Given their ubiquity, it stands to reason that these decreases reflect a highly general brain process. These task-induced power decreases are ubiquitous, and can be observed across species (including humans, macaques, rodents and cats ), sensory modalities (including visual, auditory, and somatosensory domains), and cognitive tasks (including perception, memory formation/retrieval, and language processing ). Alpha/beta activity displays an intimate link to behaviour engaging in a cognitive task produces a large reduction in the alpha/beta power (amplitude squared). When recording from the human scalp, it is the alpha and beta frequencies (8–12 Hz 13–30 Hz) that dominate. Often referred to as ‘neural oscillations’, these rhythmic fluctuations can be observed throughout the brain at frequencies ranging from 0.05 Hz to 500 Hz ( Buzsáki and Draguhn, 2004). Neuronal activity fluctuates rhythmically over time. These results indicate that alpha/beta power decreases parametrically track the fidelity of both externally-presented and internally-generated stimulus-specific information represented within the cortex. Critically, we found this effect in three unique tasks: visual perception, auditory perception, and visual memory retrieval, indicating that this phenomenon transcends both stimulus modality and cognitive task. When correlating this metric with concurrently-recorded alpha/beta power, we found a significant negative correlation which indicated that as post-stimulus alpha/beta power decreased, stimulus-specific information increased. Using representational similarity analysis, we quantified the amount of stimulus-specific information represented within the BOLD signal on every trial. Twenty-one participants completed an associative memory task while undergoing simultaneous EEG-fMRI recordings. Reducing the amplitude of these oscillations, therefore, may enhance information processing. On a macroscopic level, such synchronisation can contribute to alpha/beta (8–30 Hz) oscillations. When networks of task-irrelevant neurons fire in unison, they mask the signal generated by task-critical neurons. Massed synchronised neuronal firing is detrimental to information processing. ![]()
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