Retrieval of sentence relations: Semantic vs. syntactic deep structure

Two experiments on unaided and cued recall of sentences presented in context are reported. Key nouns in the sentences were arranged to have uniform surface functions, but to vary independently in deep syntactic category and semantic function. Cued recall for sentences in which the semantic function of actor and recipient coincided with the syntactic function of deep subject and object, respectively, was better than for sentences which did not have this normal semantic-syntactic coincidence. Unaided recall was not different for the two types of sentences. Models of sentence processing may have to represent both types of information as available to the language user.     

Syntactic awareness and verbal performance from preschool to fifth grade

Children from preschool to fifth grade were given two independent series of language tasks. The first tested aural sentence memory and was designed to assess children's ability to exploit syntactic structure and semantic cohesion to facilitate sentence recall. The second tested children's syntactic awareness, as reflected in their ability to correct grammatically deviant sentences. Results showed increases with grade level both in children's syntactic awareness and in their use of linguistic structure in sentence recall. Further, syntactic awareness increased with age, independently of vocabulary age. Syntactic awareness was significantly related both to reading achievement and to the use of syntactic structure and semantic structure to facilitate sentence recall, even with the effects of vocabulary age and grade statistically controlled. Although strongly correlated with verbal ability, syntactic awareness appears to constitute a higher-order language skill that is associated with other aspects of verbal performance.This research was carried out at the University of Melbourne and was supported by a University of Melbourne Research Development Grant.     

Syntactic complexity and elaborative processing

Memory for sentences as a function of the syntactic complexity of the sentences was examined. Sentence complexity was varied through a manipulation that involved presenting sentences in either self-embedded forms or more standard forms. Subjects performed an incidental semantic orienting task on a set of sentences varying in complexity and were subsequently tested for their recognition memory of the sentences. In Experiment 1, subjects were tested for their memory of both surface characteristics and meaning of the sentences. There were no differences caused by sentence complexity for memory for meaning. Memory for surface structure, however, was a function of sentence complexity such that there was better memory for the more complex sentences. Experiment 2 replicated the finding that the more complex sentences produced better recognition memory for surface structure. The results are interpreted within a framework that suggests that increased syntactic complexity produces more elaboration, which in turn produces better memory.     

Levels of processing of normal and ambiguous sentences in different contexts

Summary An experiment was conducted to investigate the effect of depth of semantic analysis on the recall of sentences presented for comprehension. The depth of semantic analysis was varied by presenting 48 subjects with 24 unambiguous or lexically ambiguous sentences that were either preceded by a picture or not. Each picture showed either one or both interpretations of the respective ambiguous sentence. The sentence remained on display until the subject had pressed a key to indicate that he had understood its meaning. After the presentation of all the sentences the subjects were tested for recall. Ambiguous sentences were equally well understood as unambiguous sentences, but were better recalled when their ambiguity had been noticed. The subject's awareness of sentence ambiguity, and hence the depth of semantic analysis, was found to depend on the pictorial context in which the sentences were presentend. The pictorial context was also found to affect the depth of processing of unambiguous sentences, which, when presented without a picture, were more time-consuming in comprehension and less well recalled than when preceded by a picture. These findings provide the background for a discussion of the interrelations between the comprehension of sentences, the depth of their semantic processing, and the recall of these sentences.The author gratefully acknowledges the assistance of Lorenz Sichelschmidt in collecting and analyzing data and B. Jankowski in the translation of this paper from an original German version     

Syntactic and semantic contributions to sentence comprehension in agrammatism

Five aphasic subjects, who demonstrated agrammatic speech, and eight control subjects were presented with a sentence-picture matching task in which the factors of syntactic complexity, semantic reversibility, and sentence plausibility were independently varied. A subset of the sentences was patterned after that presented by A. Caramazza and E. Zurif (1976, Brain and Language, 5, 572-583) who concluded that Broca's aphasics rely on semantic constraints instead of syntactic information for sentence comprehension. Our aphasic subjects showed the same pattern of performance on this subset of sentences. However, the results from the full set of sentence materials we tested show that the aphasic subjects could perform some sentence level syntactic analyses, even when syntactic information conflicted with semantic constraints. The aphasic subjects correctly interpreted most active and passive sentences. They failed, however, to assign thematic roles and adjectives in center-embedded relative sentences, and instead relied on nonsyntactic information. These results show that both semantic and syntactic information contributed to sentence comprehension in the aphasic subjects we tested, in contrast to previous claims that syntactic and semantic processes are completely dissociated in this population.     

An event-related fMRI study of syntactic and semantic violations

We used event-related functional magnetic resonance imaging to identify brain regions involved in syntactic and semantic processing. Healthy adult males read well-formed sentences randomly intermixed with sentences which either contained violations of syntactic structure or were semantically implausible. Reading anomalous sentences, as compared to well-formed sentences, yielded distinct patterns of activation for the two violation types. Syntactic violations elicited significantly greater activation than semantic violations primarily in superior frontal cortex. Semantically incongruent sentences elicited greater activation than syntactic violations in the left hippocampal and parahippocampal gyri, the angular gyri bilaterally, the right middle temporal gyrus, and the left inferior frontal sulcus. These results demonstrate that syntactic and semantic processing result in nonidentical patterns of activation, including greater frontal engagement during syntactic processing and larger increases in temporal and temporo-parietal regions during semantic analyses.     

Working memory and planning during sentence production

Speakers retrieve conceptual, syntactic and lexical information in advance of articulation during sentence production. What type of working memory (WM) store is used to hold the planned information before speaking? To address this question, we measured onset latencies when subjects produced sentences that began with either a complex or a simple initial noun phrase, while holding semantic, phonological or spatial information in WM. Although we found that subjects had longer onset latencies for sentences beginning with a complex noun phrase, showing a phrasal scope of planning, the magnitude of this complexity effect was not affected by any type of WM load. However, subjects made more syntactic errors (but not lexical errors) for sentences beginning with a complex noun phrase, suggesting that advance planning for these phrases occurs at a syntactic rather than lexical–semantic level, which may account for the lack of effect with various types of WM load in the current study.     

Syntactic form and semantic function

The experiments reported here were designed to investigate the effects on linguistic performance of varying the interaction between the syntactic form of sentences and their semantic function. The experimental task required subjects to decide whether pairs of sentences had the same or a different meaning. The results of Experiment I confirmed the prediction that the times taken to decide about pairs of affirmative and negative sentences would be shorter when the negative was performing its natural function of signalling a change of meaning. To a lesser extent, performance on pairs of active and passive sentences was facilitated when the two sentences meant the same thing. These results were found both with “meaningful” sentence material and with abstract x-y sentences. A second experiment provided a control for the possibility that the results were due to syntactic derivational factors rather than to the semantic function interaction.     

Cue utilization following different forms of encoding in mildly, moderately, and severely demented patients with Alzheimer's disease

The ability of patients with Alzheimer's disease (AD) to utilize semantic category cues in order to improve memory performance was examined. Categorizable lists of words or objects were presented under five different encoding conditions: (a) nouns, (b) objects, (c) objects with a semantic orienting question, (d) objects with self-generated motoric acts, and (e) objects with experimenter-instructed motoric acts. Subjects were asked to memorize the items for a free recall test, and were subsequently provided with the category names in a cued recall test. Mildly, moderately, and severely demented AD patients, and a group of normal older adults participated in the study. Results showed that normal older adults and mildly demented AD subjects were able to utilize cues to improve memory performance in all conditions. Moderately demented patients utilized cues in all conditions except in the verbal condition (condition [a]), whereas severely demented patients utilized cues only in the motoric condition (condition [e]). These results suggest that the ability to utilize category cues following a motoric encoding is preserved later in AD than the ability to utilize cues after a semantic encoding.     

Presupposition and Implication of Truth: Linguistic Deficits following Early Brain Lesions

Twenty-four children (4–17 years) with unilateral left (N = 14) or right (N = 10) hemisphere damage and 24 age-matched controls were tested on their ability to presuppose the truth of factive sentences e.g., “Max knew that he locked the door,” and to infer the truth or falsity of implicative sentences “Max remembered to lock the door.” Experimental sentence types varied according to the type of inference, the semantic features of the verb (factive vs. implicative), the presence and type of negation (lexical or syntactic), and the syntax of the complement (tensed or infinitive). Relative to age-matched controls, left lesion subjects were deficient in both their presupposition and implication performance, particularly when such inferences required the computation of negation scope. Right lesion subjects exhibited a somewhat more selective deficit; one limited to implication, but not presupposition, and one limited to lexical but not syntactic forms of negation.     

Children's recall of contextually integrable and nonintegrable episodic events

The hypothesis of this study is that children's deficiency in encoding input information may be attributed partially to a failure to fully integrate target and contextual information. Second and fourth grade children and college adults were shown sentences varying in internal integrability in a cued recall task for target nouns in the sentences. The sentences were internally semantically Congruous, Incongruous, or Anomalous. In acquisition, the subjects were told either to read the sentences (Read Encoding) or to rate the likelihood of the occurrence of the sentential event (Integration Encoding). The results showed large developmental differences in both levels of recall and the Congruity effect (superior recall for the Congruous relative to the Anomalous sentences) in the Read condition. These differences were minimized in the Integration condition. These patterns suggest young children are deficient in the contextual integration of episodic events, and, as a result, make inefficient use of semantic information in the encoding of input information.     

Sentence production and working memory

Previous research has shown that subjects can make up sentences faster from related noun pairs than from unrelated pairs. Two experiments tested the proposal that for the related pairs a subject simply has to access stored information but must make up an appropriate relation for unrelated pairs. In both studies the subjects were asked on some trials to remember a digit preload while they made up their sentences. Contrary to an initial prediction, the latencies were faster rather than slower with a preload. Furthermore, a surprise recall test at the end of Experiment 2 showed that there was no difference in the recall of related and unrelated pairs. The results were interpreted as evidence that semantic work was necessary for both types of noun pairs, and that the subjects did less semantic work with a digit preload. This interpretation was further supported by the finding that with the preload the subjects produced a narrower range of semantic relations between the noun pairs.     

Neural correlates of metonymy resolution

Metonymies are exemplary models for complex semantic association processes at the sentence level. We investigated processing of metonymies using event-related functional magnetic resonance imaging (fMRI).During an 1.5 Tesla fMRI scan, 14 healthy subjects (12 female) read 124 short German sentences with either literal (like “Africa is arid”), metonymic (“Africa is hungry”), or nonsense (“Africa is woollen”) content. Sentences were constructed so that they obey certain grammatical, semantic, and plausibility conditions and were matched for word frequency, semantic association, length and syntactic structure. We concentrated on metonymies that were not yet fossilised; we also examined a wide variety of metonymic readings.Reading metonymies relative to literal sentences revealed signal changes in a predominantly left-lateralised fronto-temporal network with maxima in the left and right inferior frontal as well as left middle temporal gyri. Left inferior frontal activation may reflect both inference processes and access to world knowledge during metonymy resolution.     

Dissociation of algorithmic and heuristic processes in language comprehension: Evidence from aphasia

Three groups of aphasic patients, Broca's, Conduction, and Wernicke's, and a nonaphasic patients control group were tested for comprehension of object-relative center-embedded sentences. The sentences were of three types: sentences in which semantic constraints between words allowed the subjects to assign a correct semantic reading of the sentence without decoding the syntax, sentences in which semantic constraints were relaxed and for which a correct reading was only possible with knowledge of syntactic relationships among words, and sentences which described highly improbable events. The subjects' task was to choose which of two pictures captured the meaning expressed in the sentence. Broca's and Conduction aphasics performed near perfectly on sentences where they could use semantic information. Their performance dropped to chance when they had to use syntactic information. These results support a neuropsychological dissociation of heuristic and algorithmic processes based primarily, though not exclusively, on semantic and syntactic information, respectively.     

Social inference and individual differences in aggression: Evidence for spontaneous judgments of hostility

This research examined the hypothesis that aggressive vs. nonaggressive individuals differ in their spontaneous trait inferences, i. e., inferences made without any conscious intention of inferring characteristics of an actor. We anticipated that spontaneous processing conditions would be more revealing of aggressive/nonaggressive differences than would conditions that prompt deliberate inference processes. We used a cued-recall paradigm. Aggressive and nonaggressive subjects were instructed to memorize sentences that were open to either hostile or nonhostile interpretations. Sentence recall was then cued by either hostile dispositional terms or by words that were linked semantically to the element of the sentences. Within the spontaneous inference condition, semantic cues prompted twice as much recall as hostile cues among nonaggressive subjects, whereas dispositional cues aided recall more than semantic cues among aggressive subjects. As predicted, within the delinerate inference conditions there were no aggressive/nonaggressive differences. The nature of spontaneous vs. deliberate inferential processes and the advantages of spontaneous inference paradigms for testing predictions about schema-based processing in aggression are discussed. © 1995 Wiley-Liss, Inc.     

Comprehending Semantic and Grammatical Violations in Italian. N400 and P600 Comparison with Visual and Auditory Stimuli

Arguments about the existence of language-specific neural systems and specifically about the independence of syntactic and semantic processing have focused on the event-related brain measures (ERPs) as tool to monitoring moment-by-moment the cognitive processes underlaid. In the present experiments, the available evidence indicates that the ERP response to semantic anomalies is at least partially distinct from the ERP response to syntactic anomalies and that two distinct processes are activated in sentences comprehension. ERPs were recorded from 10 electrodes while subjects read (Experiment 1) or listened (Experiment 2) to sentences containing semantic or syntactic violations. Final-words that were inconsistent with the sentence context elicited a negative-going wave at about 400 ms poststimulus, whereas penultimate-word incongruous with the grammatical structure (subject–verb non-agreement) elicited a positive-going wave about 600 ms poststimulus. No differences based on the perceptual modality of the stimulus (visual or auditory) nor different ERP correlates as a function of task-relevance (explicit/implicit task induction) were found. The implications of our results for Italian language are explained.     

Making sense of sentences in schizophrenia: electrophysiological evidence for abnormal interactions between semantic and syntactic processing

Event-related potentials to critical verbs were measured as patients with schizophrenia and healthy controls read sentences word by word. Relative to their preceding context, critical verbs were (a) congruous, (b) incongruous and semantically unrelated to individual preceding words (pragmatic-semantic violations), (c) incongruous but semantically related to individual preceding words (animacy-semantic violations), or (d) syntactically anomalous. The N400 was modulated normally in patients, suggesting that semantic integration between individual words within sentences was normal in schizophrenia. The amplitude of the P600 to both syntactic and animacy-semantic violations was reduced in patients relative to controls. The authors suggest that, in schizophrenia, an abnormality in combining semantic and syntactic information online to build up propositional meaning leaves sentence processing to be primarily driven by semantic relationships between individual words.     

汉语句子理解中语义分析与句法分析的关系

两个实验研究了中文句子理解中句法分析与语义分析的关系。实验1采用被试者自控阅读速度的方法,要求被试者对每个句子(合理句或不合理句)进行语法判断。结果表明,在歧义词(AW)和解歧词(DAW)上,合理句与不合理句的错误率存在显著差异,而反应时差异不显著。实验2研究了语境对句子理解的作用。结果表明,在有语境和无语境条件下,两类句子在歧义词和解歧词上的反应时,均有明显的差异。这些结果支持了句子理解中句法与语义加工的弱相互作用模型。     

语义信息复杂度对二语者英语被动句加工的影响

采用英语所独有且非常重要的句法结构——被动语态作为语言材料,选取某些可以在句子中的词汇顺序基本没有变化的情况下转换为汉语句式（汉语“被”字句）的“直译型”被动句以及必须根据其意义进行句式转换方能形成相应的汉语句式（汉语主动句）的“意译型”被动句作为实验材料,探讨了在动词语义复杂条件下二语熟练度（包括晚期中等熟练者和高熟练者）对被动句加工过程的影响。结果表明：高熟练者正确率均高于中等熟练者,说明在动词语义复杂的情况下熟练度依然可以预测英语被动句实时加工的程度和水平。此时,语义违例的正确率最高、反应时最短,句法违例句则与之相反。双违例引发的N400效应显著,正确句和句法违例均未引发负向的N400;高熟练者P600的波幅明显高于中等熟练者,句法违例和双违例引发的P600效应最显著。行为指标支持语言间句法加工相似性效应——直译句反应快、正确率高。ERP数据则得出了与之相反的结果：直译句比意译句诱发出更大的N400效应,意译句则引发了较大的P600。上述结果进一步说明二语熟练度对语言间句法加工相似性效应具有很强的调节作用。     

Normalization in paraphrase and recall: Effects of processing,grammatical article type,and retention interval

Investigations of semantic normalization of discourse have not generally controlled for perceived connectiveness of materials, depth of processing, and retention interval. The current experiment investigated semantic normalization in paraphrase and recall as a function of whether sentences were paraphrased or merely copied, of whether sentences were perceived by subjects to be connected or unrelated, and of retention interval. Results indicated that significantly more normalization occurred in paraphrase than in recall, that more normalization and better recall occurred when sentences were perceived as related, and that there was more normalization and better recall when sentences were paraphrased than when they were copied. No significant differences in normalization were found as a function of retention interval. Results are discussed in terms of depth of processing and a need for learners to integrate congruent and discrepant material into cohesive entities by use of grammatical articles, article changes, and intrusions that psychologically connect unrelated sentences.