FIAS Scientific Report 2011 - Frankfurt Institute for Advanced Studies ...

Non-stationarity of neuronal activity
(LOEWE Neuronale Koordination Forschungsschwerpunkt Frankfurt (NeFF))
Collaborators: D. Nikolić, R.C. Mureşan, W. Feng, W. Singer
When computing a cross-correlation histogram, slower signal components can hinder the detection of
faster components, which are often in the research focus. For example, precise neuronal
synchronization often co-occurs with slow co-variation in neuronal rate responses. We developed a
method – dubbed scaled correlation analysis – that enables the isolation of the cross-correlation
histogram of fast signal components. The method computes correlations only on small temporal scales
(i.e. on short segments of signals such as 25 ms), resulting in the removal of correlation components
slower than those defined by the scale. Scaled correlation analysis has several advantages over
traditional filtering approaches based on computations in the frequency domain. Among its other
applications, the method can assist the studies of precise neuronal synchronization.
Figure: Time resolved auto-correlation of local field potentials computed with (top) and without scaled
correlation (bottom).
Related publication:
D. Nikolić, R.C. Mureşan, W. Feng and W. Singer, Scaled correlation analysis: A better way to
compute a cross-correlogram. European Journal of Neuroscience (to appear)
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