https://sccn.ucsd.edu/eeglab/download/eeglab_jnm03.pdf

EEGLAB: an open source toolbox for analysis of single-trial EEG dynamics including independent component analysis.

The emergence of a unified cognitive moment relies on the coordination of scattered mosaics of functionally specialized brain regions. Here we review the mechanisms of large-scale integration that counterbalance the distributed anatomical and functional organization of brain activity to enable the emergence of coherent behaviour and cognition. Although the mechanisms involved in large-scale integration are still largely unknown, we argue that the most plausible candidate is the formation of dynamic links mediated by synchrony over multiple frequency bands.

The brainweb: phase synchronization and large-scale integration.

Classical theories of sensory processing view the brain as a passive, stimulus-driven device. By contrast, more recent approaches emphasize the constructive nature of perception, viewing it as an active and highly selective process. Indeed, there is ample evidence that the processing of stimuli is controlled by top-down influences that strongly shape the intrinsic dynamics of thalamocortical networks and constantly create predictions about forthcoming sensory events. We discuss recent experiments indicating that such predictions might be embodied in the temporal structure of both stimulus-evoked and ongoing activity, and that synchronous oscillations are particularly important in this process. Coherence among subthreshold membrane potential fluctuations could be exploited to express selective functional relationships during states of expectancy or attention, and these dynamic patterns could allow the grouping and selection of distributed neuronal responses for further processing.

/pdf/dynamic-predictions-oscillations-and-synchrony-in-top-down-g571k2ka9j.pdf

Dynamic predictions: Oscillations and synchrony in top–down processing

EEG alpha oscillations: The inhibition–timing hypothesis

Dynamic functional connectivity: Promise, issues, and interpretations

http://www.ini.uzh.ch/~johannes/vonstein_ijp2000.pdf

Different frequencies for different scales of cortical integration: from local gamma to long range alpha/theta synchronization.

Perception and cortical responses are not only driven “bottom-up” by the external stimulus but are altered by internal constraints such as expectancy or the current behavioral goal. To investigate neurophysiological mechanisms of such top-down effects, we analyzed the temporal interactions of neurons on different levels of the cortical hierarchy during perception of stimuli with varying behavioral significance. We found that interareal interactions in a middle-frequency range (θ and α; 4–12 Hz) strongly depend on the associated behavior, with a phase relationship and a layer specificity indicating a top-down-directed interaction. For novel unexpected stimuli, presumably processed in a feed-forward fashion, no such interactions occurred but high-frequency interactions (γ; 20–100 Hz) were observed. Thus corticocortical synchronization reflects the internal state of the animal and may mediate top-down processes.

https://www.pnas.org/content/pnas/97/26/14748.full.pdf

Top-down processing mediated by interareal synchronization

This paper discusses the notion of representation and outlines the ideas and questions which led to the organization of this volume. We argue for a distinction between the classical view of referential representation, and the alternative concept of system-relative representation. The latter refers to situated cognitive processes whose dynamics are merely modulated by their environment rather than being instructed and determined by it.

Understanding representation in the cognitive sciences

This study was performed to test the usefulness of the EEG as a research instrument for music psychology in individuals. Measuring the degree of functional interrelatedness of brain areas by coherence estimates has turned out to be more efficient than amplitude mapping. Therefore, the method, based on the analysis of EEG periods of at least 1 min, has been expanded to estimate all possible coherence values between the 19 electrodes (i.e., 171 values) and to observe any significant changes in those values caused by different musical tasks. This report concerns observations in a total of 49 healthy subjects (29 male and 20 female). The main goal of this study was to determine the degree of engagement of either hemisphere in the processing of music. Two items were shown to indicate hemispheric involvement: (1) the topographic distribution of "focal points of coherence" (brain areas participating in coherence changes with respect to a great number of other brain areas) and (2) the number of intrahemispheric coherence increases. In most cases, both items seem to focus on the same hemisphere. Taking these as parameters for hemispheric engagement, the following principal observations were made: the beta bands (and particularly their uppermost ranges) seem to play a major role in the processing of music; the hemispheric engagement, however, need not be the same for each frequency band. No hemisphere seems to be preferred. When listening to music is shifted between different styles, laterality may change. When the same tasks are repeated at several weeks9 intervals, a fairly large degree of consistency is found. Imagining music and composing clearly differs from listening by activating many more coherence increases in the beta band and by an increasing percentage of hemispheric interaction. This kind of analysis may also provide some clues as to how a piece of music is processed by an individual. The coherence changes observed may represent events taking place in a system of differential attention that selects and orders the sensory inputs before the musical material is further processed at higher order hierarchical levels.

EEG Coherence and Musical Thinking

Position Paper. Different Facets of Representation. Computational Approaches. Cognition as a Dynamical System. Relevance of Action for Representation. Symbol Grounding and Language. Communication and Social Coupling. Qualitative Aspects of Representation and Consciousness. Constructivism. Appendix.

Astrid von Stein

Papers

Different frequencies for different scales of cortical integration: from local gamma to long range alpha/theta synchronization.

Top-down processing mediated by interareal synchronization

Understanding representation in the cognitive sciences

EEG Coherence and Musical Thinking

Understanding representation in the cognitive sciences : does representation need reality?