>do you have any experience with the effect of repetition of (picture)
>stimuli on the BOLD response? Is there any habituation or saturation
>etc., an if so, after how many repetitions?
You may have a look at
Bandettini et al: Characterization of cerebral blood
oxygenation and flow changes during prolonged brain
activation. HBM, 5:93-109, 1997
Condon et al: Habituation-like effects cause a significant
decrease in response in MRI neuroactivation during visual
stimulation. Vision Research, 37,9:1243-1247, 1997
Krueger et al: Stimulus dependence of oxygenation-sensitive
MRI responses to sustained visual activation. NMR in
Biomedicine, 11:75-79, 1998
We tested several stimuli and protocols with results
according to Bandettini et al. Furthermore one has to think
of statistical power issues concerning the number of images
(see mailbase archive) and the effects of attention. The
latter should be considered carefully especially when you
plan protocols lasting for more than about four minutes.
Best regards,
Christian Kaufmann
Max Planck Institute of Psychiatry
NMR Study Group
Kraepelinstrasse 2-10
80804 Munich
Germany
www.mpipsykl.mpg.de
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