Stimuli on each trial varied either only by a rotated vowel (in the vowel test) or only by a rotated consonant (in the consonant test); trials were repeated for all possible rotated vowel and consonant combinations.
The task was to search for a rotated T among an array of 24 items and respond present or absent via button press (see Fig. 1).
Three factors F1, F2 and F3 (F1 > F2 > F3 in importance) were chosen for a rotated component matrix.
This holds for all categories of rotated objects except hands.
For the rotated targets and rotated distractors condition, no significant differences between non-blinkers and blinkers were found in latency (ps>.12) or amplitude (ps>.36) for electrode Pz using independent samples t-tests.
For the rotated QAM, the optimal rotation angles are investigated for the MIMO system according to the maximizing AMI criterion.
Relative to the variability of cortical responses [27], the temporal precision of the first occurrence of each pattern was rather high: The range of jitter (min-max) across trials was ∼15 ms for "Z", ∼23 ms for "enlarged B", and ∼21 ms for "rotated A".
Following factor extraction and factor rotation, a weighted (synthetic) Q-sort is produced for each rotated factor by using a weighted averaging method to calculate the score for each statement in the factor array [ 27].
The size of this effect was reduced in Experiment 1b, but this probably reflects the fact that the difference in frequency between the endpoint stimuli was much larger for the spectrally rotated stimuli (60 Hz for speech, 200 Hz for the spectrally rotated speech).
A mask was then created for the rotated map.
