Martha N. Havenith

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Many complex systems give rise to events that are clustered in space and time, thereby establishing a correlation structure that is governed by power law statistics. In the cortex, such clusters of activity, called "neuronal avalanches," were recently found in local field potentials (LFPs) of spontaneous activity in acute cortex slices, slice cultures, the(More)
The analysis of neuronal information involves the detection of spatiotemporal relations between neuronal discharges. We propose a method that is based on the positions (phase offsets) of the central peaks obtained from pairwise cross-correlation histograms. Data complexity is reduced to a one-dimensional representation by using redundancies in the measured(More)
The synchronized activity of cortical neurons often features spike delays of several milliseconds. Usually, these delays are considered too small to play a role in cortical computations. Here, we use simultaneous recordings of spiking activity from up to 12 neurons to show that, in the cat visual cortex, the pairwise delays between neurons form a preferred(More)
Stimulus-induced changes in oscillation frequencies may affect information flow in the brain. We investigated whether the oscillation frequency of spiking activity in cat area 17 changes as a function of the drifting direction of sinusoidal gratings. Oscillation frequencies were tuned to specific drifting directions, such that some directions induced higher(More)
Recent evidence indicates that sub-millisecond delays in neuronal spiking activity may be relevant for neural coding. Estimates of these delays are usually made from cross-correlation histograms (CCH) binned to 1ms. We investigated the degree to which it is possible to measure delays with sub-millisecond precision when one computes CCHs with bin sizes > or(More)
Recent studies suggested that small time delays among synchronized responses can convey information about visual stimuli. We compared these delays across different types of synchronized signals: single-unit action potentials, multi-unit action potentials, and local field potentials obtained with invasive recordings from cat visual cortex and(More)
The investigation of distributed coding across multiple neurons in the cortex remains to this date a challenge. Our current understanding of collective encoding of information and the relevant timescales is still limited. Most results are restricted to disparate timescales, focused on either very fast, e.g., spike-synchrony, or slow timescales, e.g., firing(More)
Recent studies suggested that small time delays among synchronized responses can convey information about visual stimuli. We compared these delays across different types of synchronized signals: single-unit action potentials, multi-unit action potentials, and local field potentials obtained with invasive recordings from cat visual cortex and(More)
Gerald Hahn , Thomas Petermann, Martha N. Havenith, Shan Yu , Wolf Singer , 5 Dietmar Plenz, and Danko Nikolić 3 6 7 8 Department of Neurophysiology, Max-Planck Institute for Brain Research, Frankfurt/M, Germany 9 Section on Critical Brain Dynamics, Porter Neuroscience Research Center, National Institute of Mental 10 Health, Bethesda, USA 11 Frankfurt(More)
In the past two decades, functional Magnetic Resonance Imaging has been used to relate neuronal network activity to cognitive processing and behaviour. Recently this approach has been augmented by algorithms that allow us to infer causal links between component populations of neuronal networks. Multiple inference procedures have been proposed to approach(More)
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