To my knowledge, there are only a few experimental studies that have tested children’s interpretation of parallelism and contrastive stress in structures with pronouns.13 Most of these studies, with the exception of
one (Chomsky, 1971), provide results indicating that children can implement parallelism but fail to correctly interpret contrastive stress.14
Maratsos (1973) tested children’s interpretation of contrastive stress in sentences exemplified in (18) and (19), using an act out task.15
13A few studies have indicated that children are sensitive to contrastive stress but are
unable to use it in the same way adults do in structures without parallelism (in comprehension Hornby, 1973; Tavakolian, 1974; and in production Hornby & Hass, 1970; Cutler & Swinney, 1987).
14 Chomsky (1971) used an act out task to test pronouns that received contrastive
stress in sentences such as (i), where the unstressed pronoun was reduced.
(i) THE HORSE pushed the man, and then the elephant came along and pushed
‘im/HIM.
She tested 34 children of which 29 performed adult-like on stressed pronouns.
15 Like in Chapter 2, italics indicate coreference and capitals indicate contrastive
(18) Ann jumped over the old woman, and then Harry jumped over
her/HER.
(19) Ann jumped over the old woman, and then she/SHE jumped over Harry.
He found that children perform at chance level with stressed pronouns in both subject and object position. Their performance on the unstressed conditions was significantly above chance (80%). In a similar study using the same paradigm and testing only pronouns in the object position of the second conjunct, McDaniel & Maxfield (1992) also found that children’s performance on parallelism is above chance. They found chance performance on contrastive stress in the same children.
As was already discussed in Chapter 3 (see section 3.3.3.), Solan (1983) tested children’s comprehension of parallel structures with pronouns. To summarise, he found that children apply parallelism of thematic roles, which, according to him, is unlike that of adults who use both parallelism of thematic and of grammatical roles equally often. Another study that was discussed in Chapter 3 (see section 3.2.4, p.p. 103) was conducted by Baauw, Ruigendijk & Cuetos (in preparation). They tested the comprehension of parallelism and contrastive stress by Spanish children and agrammatic aphasic patients, and used exactly the same materials (pictures) I used in Experiment 3. They found that both groups had more difficulties with stress than with parallelism. With regard to latter, the children and agrammatic patients they tested performed better on the conditions where the pronoun was in the subject position of the second conjunct. They follow Zuckerman, Vasić, Ruigendijk & Avrutin’s (2002) claim that children and agrammatic patients use topic preference as a default mechanism when they run into problems with pronoun resolution in these constructions. This claim is also in line with the claim I make in Chapter 2 about the pattern of errors in agrammatism.
5.4.2 Experiment 7
5.4.2.1 Subjects
28 children (mean age= 5.3) were tested in this experiment, whose results are compared to a control group of 15 adults (age 35-84, mean age 56.6).
5.4.2.2 Materials and procedure
A picture selection task was used to test the children’s interpretations of pronouns in sentences testing subject and object parallelism and
contrastive stress. The experiment testing these two types of sentences was embedded in Experiment 5, discussed in section 5.2.2.2.
The four conditions that were relevant for this study were represented by 48 sentences in total, 12 per condition (see Appendix F for all test sentences). The experimental conditions were the following:
Unstressed subject pronoun and Unstressed object pronoun testing the
parallelism constraint; Stressed subject pronoun and Stressed object pronoun testing the comprehension of contrastive stress.
Children were tested with the picture selection task used and described in Chapter 3. The only difference was that, in the experiment with children the characters portrayed in the pictures were Teletubbies. For a detailed discussion of experimental items, see section 3.2.2, Chapter 3. Examples of the experimental items are given below (Unstressed/Stressed subject pronoun in (20) and Figure 5.3; Unstressed/
Stressed object pronoun in (21) and Figure 5.4).
(20) Eerst heeft Tinky-Winky Dipsy geknepen en daarna heeft hij/HIJ Lala geknepen.
First Tinky-Winky pinched Dipsy and then he/HE pinched Lala. (21) Eerst heeft Lala Po geknepen en daarna heeft Tinky-Winky
haar/HAAR geknepen.
Figure 5.3
Figure 5.4
Unstressed/Stressed object condition
5.4.2.3 Results
The percentages of correct responses by children, controls and agrammatic aphasic patients (results from Experiment 3, Chapter 3, section 3.2.3) are given in Table 5.6 (for individual data, see Appendix F, Table F.3). I examined whether the whole group of 28 children that were tested in this experiment performed differently from chance-level on the four experimental conditions. Children always pointed at either the correct picture or the direct distractor. Therefore, as before, I assume that chance level performance on this task was 50%, regardless of the fact that 33% would be the real chance level when randomly chooses between
three pictures. A binomial test showed that their results on all four conditions did not differ from chance (Unstressed subject pronoun - p=0.06; Unstressed object pronoun - p=0.07; Stressed object pronoun - p=0.08;
Stressed subject pronoun - p=0.05).
Table 5.6
Percentages correct responses on all four experimental conditions.
I also compared children’s performance on the two conditions testing parallelism (Unstressed subject pronoun and Unstressed object pronoun conditions). There was no significant difference between their performances on these two conditions (Wilcoxon Signed Ranks Test - Z=-. 158, p<0.875). The two stressed conditions also did not differ from each other (Wilcoxon: Z=-1.132, p<0.258).
In order for children to correctly interpret contrastive stress, they must first correctly apply the parallelism constraint. I checked whether children who can apply parallelism are also able to interpret contrastive stress. I therefore isolated 18 children who showed above chance level performance on parallelism. They were treated as a separate group, whose results are also reported in Table 5.6. This group of children performed above chance on the Unstressed subject pronoun (binomial test - p=0.0005) and Unstressed object pronoun (binomial test - p=0.034) conditions and at chance on the Stressed subject pronoun (binomial test – p=0.733) and Stressed object pronoun conditions (binomial test - p= 0.088). There was no difference between their responses on the Unstressed subject
pronoun condition vs. Unstressed object pronoun condition (Wilcoxon: Z=-
1.045, p<0.296). They performed significantly better on the Stressed object
pronoun condition than on the Stressed subject pronoun condition
(Wilcoxon: Z=-1.924, p<0.054).
For the 18 children that performed above chance on the parallelism constraint, I grouped the conditions together based on the expected antecedent, in order to check their error pattern. In both the Unstressed
subject pronoun and Stressed object pronoun conditions, the pronoun refers
to the subject in the first conjunct. In the Unstressed object pronoun and
Stressed subject pronoun conditions, on the other hand, the pronoun refers
to the object of the first conjunct. I compared the results of the two
Unstressed subject pronoun Unstressed object pronoun Stressed subject pronoun Stressed object pronoun Children (n=28) 55.2 54.9 50.4 51.7 Children (n=18) 61.8 57.3 48.4 55.9 Controls (n=15) 96.4 79.9 45.8 56.7 Broca’s (n=8) 76.6 57.5 81.3 83.5
conditions where the subject was the expected response to the two conditions where the object was the expected response and I found a significant difference between the two sets of results in both children (t(18)=1.98, p=0.03) and adults (t(15)=2.23, p=0.02). Both children and adult controls made significantlyfewererrors on conditions where the pronoun in the second clause referred to the subject DP of the previous clause.
5.4.3 Discussion
The group of 28 children I tested in this experiment performed at chance on all experimental conditions. These children, when treated as a group, failed to apply parallelism. They also failed to shift reference when contrastive stress was applied to these structures. Their performance was equally poor on all experimental conditions. These results clearly indicate that children’s problems with pronouns are not limited to structures where Rule-I is at play. In the structures tested here it is related to a failure to assign reference through discourse operations of parallelism, whose mechanics I discussed in detail in Chapter 3 (sections 3.1.2. and 3.3.3.).
The 18 children that scored above chance on the unstressed conditions (parallelism conditions) and were treated as a separate group performed at chance on the contrastive stress conditions. They filed to shift reference in the contrastive stress conditions. I further examined the pattern of errors of this group in order to compare their error pattern to the one exhibited by the agrammatic patients I tested, and the Spanish children and agrammatic patients tested by Baauw et al. (in prep). I found a similar pattern in children as in agrammatic patients (see Chapter 3 for details) as well as in the Spanish children and agrammatic patients reported by Baauw et al. (in prep); children’s scores were significantly higher on conditions where the pronoun referred to the subject than on the conditions where the pronoun referred to the object of the first clause.
I would like to argue that, like Broca’s aphasic patients, children have problems with the parallelism requirement. Recall that in order to apply parallelism, the syntactic and lexical-semantic information for both conjuncts needs to be retained in working memory so that it can be properly mapped onto discourse. Once this information is incorporated in the file cards representing events and individuals, the relationship between these also needs to be kept in working memory. I assume that children also have limited processing capacity and the application of the parallelism constraint goes beyond their capacity. Nevertheless, their
errors are not random. Like in agrammatic patients, in the pre-school children I tested the default mechanism of topic preference provides the antecedent for the pronoun.