Contents

Results & outcomes

Hypothesis 1

Firstly, a typical P300 effect should be visible

difference wave target - standard

DW_tar_sta

a typical P300 pattern could be observed (second component).

Hypothesis 2

The behavior of the repetition positivity after a deviant could:

  • decrease

  • vanish

difference wave last - first repetition

DW_lr_fr

no difference could be found. Also in the Grandaverage standard there is no component looking like a repetition positivity. As no repetition positivity could be found, I can not analyze the second hypothesis

Grandaverage standard

ga_sta

Grandaverage last repetition

ga_lr

Discussion

The P300 effect could be observed indicating that the oddball task itself has worked. The absence of the repetition positivity cound have several reasons:

  1. there is no difference in RP between the first and kast repetition This is rather unlikely as in ther Grandaverage of the standard and also the last repetition there was no component indicating the RP

  2. The Design of the study was different to other studies investigating RP - with this desing the RP effects do not show up Other studies investigating the RP did use the first deviant as the new standard so the standard changed several times. Moreover ther participants had the eyes closed in this experiment but not in the previous experiments investigating the RP

  3. I would have needed further steps in the preprocessing part Some electrodes of some participants were still noisy

Grand averages

Grandaverage standard

ga_sta

Grandaverage target

ga_tar

Grandaverage non target

ga_nontar

Grandaverage first repetition

ga_fr

Data analyses Poster & manuscript