AW: [Eeglablist] alpha like noise
i.kirk at auckland.ac.nz
Wed Oct 19 13:55:14 PDT 2005
All v. good refs
-you might want to look at Worden et al., J. Neurosci 20 RC63, 2000
On 19 Oct 2005 at 9:16, Sarnthein Johannes wrote:
> Hi Maarten,
> You are probably looking at real data, leave it in.
> There are several reports of cognitive alpha processes,
> for example in expectancy and also working memory.
> See some references below.
> Petsche H, Kaplan S, von Stein A, Filz O.
> The possible meaning of the upper and lower alpha frequency ranges for
> cognitive and creative tasks. Int J Psychophysiol. 1997
> Von Stein et al.
> von Stein A, Sarnthein J.
> Different frequencies for different scales of cortical integration:
> from local gamma to long range alpha/theta synchronization. Int J
> Psychophysiol. 2000 Dec 1;38(3):301-13
> Jensen et al
> Klimesch Group
> Basar Schurmann Group
> and some others
> -----Ursprüngliche Nachricht-----
> Von: eeglablist-bounces at sccn.ucsd.edu
> [mailto:eeglablist-bounces at sccn.ucsd.edu] Im Auftrag von Maarten
> Mennes Gesendet: Dienstag, 18. Oktober 2005 11:32 An:
> eeglablist at sccn.ucsd.edu Betreff: [Eeglablist] alpha like noise
> Dear all,
> During some of the tasks we used in our lab we encountered a sort of
> alpha-wave-like noise in our EEG-data (see figures in attachment).
> However, subjects were fully awake and had their eyes opened.
> This alpha-noise was sometimes stimulus locked as in the attached
> figure, however, most of the time present in clear bursts. In addition
> this noise was not always limited to the posterior channels where you
> would expect the true alpha waves.
> We did try a number of techniques in order to filter this noise out,
> but did not succeed. ICA for example could not confine this noise to
> one component.
> Has anyone else on this group encounterd this kind of noise in your
> data and if so, what did you do in order to prevent or filter out
> these wave-patterns?
> Would using more electrodes than the current 19 enable ICA to isolate
> this noise in more confined components?
> yours sincerely,
> Maarten Mennes
> Maarten Mennes
> Ph.D. Student
> Laboratory for Neuropsychology
> Department of Pediatrics
> UZ Gasthuisberg, O&N
> Herestraat 49
> 3000 Leuven
> Disclaimer: http://www.kuleuven.be/cwis/email_disclaimer.htm
> eeglablist mailing list eeglablist at sccn.ucsd.edu
> Eeglablist page: http://sccn.ucsd.edu/eeglab/eeglabmail.html
> To unsubscribe, send an empty email to
> eeglablist-unsubscribe at sccn.ucsd.edu
Ian Kirk, PhD
Research Centre for Cognitive Neuroscience,
Department of Psychology,
University of Auckland, Private Bag 92019,
Auckland, New Zealand.
Tel: (09)373-7599 X 88524(office) 88421(lab)
e-mail: i.kirk at auckland.ac.nz
More information about the eeglablist