Hello all!
I am refering to the paper of Henson et al 2002 NeuroImage 15, 83-95,
about the Latency differences.
I would like to use this technique.
I am right when I proceed as follows?
a) integrate temporal derivatives into my first level model
b) calculate the beta for the hrf_<each condition> as a [1 0]
c) calculate the beta for the td_<each condition> as a [0 1]
d) use the image calculator to create the latency_image_<each condition>
using the formula
2C/(1+exp(D beta2/beta1)) - C;
where C=1.78, D=3.1 (Henson et al 2002, Neuroimage 15, p86)
e) enter these latency_images into the second level stats (ANOVA).
f) And the last question: Is the above formula correctly entered into
the ImageCalculator when doing:
f = '(2*1.78./(1+exp(3.1*i2./i1))) - 1.78' ( I mean, I do get some
imges, but are they correct??)
Thank you very much for verification!
Markus
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