Using ambiguous nomenclatures to extensively describe different behaviors is far from optimal. The word “oscillator” is widely used but loosely defined in the cognitive neuroscience field. Finally, we provide a framework for refocusing questions away from the presence of an oscillation and toward an ever greater specificity of the kinds of nonlinear dynamics which could yield the neural and behavioral data that we study. We then use this mathematical model to test (and often reject) certain commonly assumed predictions. We do so by first providing a grounded definition of an oscillator, both generally and by means of simple mathematical equations that can be used to generate valid predictions of its behavior. Instead, we seek to reground ourselves in dynamic systems theories that have studied oscillations in detail and to ensure that the predictions and assessment criteria that we agree upon as a field are adequately justified. Our goal is not to decide whether oscillators do or do not play a critical role in brain function nor to discuss the advantages of such a mechanism. A basic analysis of how oscillations are generated will reveal 2 important points: (1) the line between oscillation and not is blurred-a leaky integrate-and-fire model is both an oscillator and a model of evoked responses-and (2) there is great heterogeneity in their possible mechanisms, each leading to different behaviors and predictions. Presumably, the goal of our research is to study not the phenomena but their underlying mechanisms. Oscillations may be generated by any number of means. We suggest that the question itself is ill-posed. What predictions can we use to tease these hypotheses apart, particularly, when the predicted neural recordings are so similar? This passive system relies on some added mechanisms (such as the contingent negative variation, e.g., ) to support higher-order processes. Perhaps the data can be explained by a passive system whose seeming rhythmicity only reflects the rhythm of the input. These papers propose a neural oscillator in the auditory cortex entrained to acoustic stimuli to support a number of important cognitive functions in audition such as attention, prediction, and segmentation. In this field, a wealth of data provides evidence for rhythmic activity approximately 4 Hz in the auditory cortex that tracks the rhythms in sound. This is because it focuses the field on determining the presence of an oscillation as being a satisfying end goal of a research program, while, instead, it is only a starting point.Īn example of this kind of dialog persists in the domain of speech and sound perception. It is our feeling, as researchers who have certainly contributed to this debate, that the discussion no longer provides any tangible benefits to the field. The result is that more effort is spent on debating an oscillation’s presence than profiting from its advantages. On the other hand, there exists a reactive trend invoking words like “epiphenomenon,” “evoked response,” and “exhaust fumes” which seeks to explain away any oscillative finding (perhaps even when they are). On the one hand, there is a tendency to doggedly look for (and often find) oscillations everywhere (perhaps even where they are not). A close look at their work could guide neuroscience toward an explanation of neural function and its consequences.ĭespite the potential advantages, it seems that at least a portion of the field is stuck in a loop, debating whether neural oscillations are or are not a useful concept worthy of study. Engineers and physicists have studied oscillators to build and understand physical phenomena long before neuroscientists grew interested in them. Second, oscillatory dynamics are extremely well studied. While these rhythms may occur at different timescales, their presence across brain regions and species is more the rule than the exception. Why is research on oscillations so pervasive throughout the field? First, because oscillatory behavior seems to be one of those exceedingly illusive universals of brain function. For a century, their implication and role have been studied in nearly every cognitive domain and species. It is documented here for convenience.Neural oscillations are a critical phenomenon in neuroscience. This structure is part of the Platform SDK and is not declared in Dsound.h. For formats that require additional information, this structure is included as the first member in another structure, along with the additional information. Only format information common to all waveform-audio data formats is included in this structure. The WAVEFORMATEX structure defines the format of waveform-audio data.
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