Electrophysiological Evidence for Sentence Comprehension - Wings

word order strongly affects sentence comprehension in SLI children (Babić, 1995);
therefore, child’s failure to comprehend the stimulus sentence and a very probable
problem of keeping the child’s attention would definitely affect the measurements. Since
the experiment is designed primarily for children, it will be referred to as the ‘tense-chi’
experiment.
The experiment consists of 200 stimulus sentences. One hundred sentences have a
violation in tense, i.e. a mismatch between the auxiliary and main verb, as in the ‘tense’
experiment. The main verb follows the auxiliary verb, which is a clitic after the first word
in the sentence (as described and prescribed in Croatian grammars, e.g. Katičić, 1986).
The direct object follows the main verb. Therefore, each stimulus sentence consists of
three (phonological) words: the subject and its clitic (auxiliary verb), the main verb and
the object. The stimuli were presented visually in a word-by-word manner. Each word
was presented for 600 ms with ISI of 1100 ms. The interval between the sentences was
1700 ms. The sequence file was designed to allow slowing down the sequence if the
stimuli were too fast for SLI children. As in all other experiments, after each 35-40
sentences a pause was inserted to allow participants head movements and more intensive
eye blinking. The participants were asked to make a grammaticality judgment after each
sentence by pressing the button on the response pad.
4.2.4. Behavioral tests
Reaction time. Two kinds of behavioral tests were employed: reaction time was measured
in all ERP experiments in order to keep the participants alert. However, in ‘case’ and
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