Does this look like what you're getting? (n.b. I'm using the reprex package here, which ensures that you can run the code and get the same thing. I copied and pasted the data from the table you have above using the datapasta package. For on using reprex in the community site, check out the reprex FAQ.).
dat <- tibble::tribble(
~participant, ~gender, ~age, ~name, ~stimulusNr, ~stimulusFinalSound, ~stimulusSyllableCount, ~response, ~reactionTime, ~accuracy,
1, "W", 20, "Leonie", 27, "V", 2, "right", "4.658.930.309.931.340", 1,
1, "W", 20, "Leonie", 48, "K", 2, "left", "8.419.140.877.029.390", 1,
1, "W", 20, "Leonie", 43, "V", 2, "left", "3.019.711.804.252.690", 1
)
tibble::glimpse(dat)
#> Observations: 3
#> Variables: 10
#> $ participant <dbl> 1, 1, 1
#> $ gender <chr> "W", "W", "W"
#> $ age <dbl> 20, 20, 20
#> $ name <chr> "Leonie", "Leonie", "Leonie"
#> $ stimulusNr <dbl> 27, 48, 43
#> $ stimulusFinalSound <chr> "V", "K", "V"
#> $ stimulusSyllableCount <dbl> 2, 2, 2
#> $ response <chr> "right", "left", "left"
#> $ reactionTime <chr> "4.658.930.309.931.340", "8.419.140.877.02…
#> $ accuracy <dbl> 1, 1, 1
Created on 2018-10-08 by the reprex package (v0.2.1.9000)