Cognitive strategies in discourse processing: A comparison of Chinese and English speakers

Three experiments tested the hypothesis that, when processing a normative language, individuals tend to adopt the discourse processing strategies that they use in their native language. In a natural language processing task, native speakers of English and Chinese read English passages that were heavily loaded with zero anaphora. Native Chinese speakers found the passages more comprehensible than did native English speakers, presumably because zero anaphora occurs much more often in Chinese than in English. However, in an artificial laboratory task, native Chinese speakers did not find it easier to recover the missing referents than did native English speakers, suggesting that the two groups were equally capable of reference retrieval although they differed in their natural language discourse-processing strategies. These results suggest that the strategies used for processing foreign-language discourse are influenced by those used to process native-language discourse.This research was supported in part by Dean's Small Grants from the Graduate School of the University of Colorado to Liang Tao and United States Army Research Institute Contracts MDA903-90-K-0066 and MDA903-93-K-0010 to the University of Colorado (Alice Healy, Principal Investigator).We thank Barbara Fox, Lise Menn, and Nanfang Jiang for stimulating discussions about this research.An earlier version of this paper was presented at the First International Conference on Chinese Linguistics held in Singapore, 1992.     

The resilience of gesture in talk: gesture in blind speakers and listeners

Spontaneous gesture frequently accompanies speech. The question is why. In these studies, we tested two non‐mutually exclusive possibilities. First, speakers may gesture simply because they see others gesture and learn from this model to move their hands as they talk. We tested this hypothesis by examining spontaneous communication in congenitally blind children and adolescents. Second, speakers may gesture because they recognize that gestures can be useful to the listener. We tested this hypothesis by examining whether speakers gesture even when communicating with a blind listener who is unable to profit from the information that the hands convey. We found that congenitally blind speakers, who had never seen gestures, nevertheless gestured as they spoke, conveying the same information and producing the same range of gesture forms as sighted speakers. Moreover, blind speakers gestured even when interacting with another blind individual who could not have benefited from the information contained in those gestures. These findings underscore the robustness of gesture in talk and suggest that the gestures that co‐occur with speech may serve a function for the speaker as well as for the listener.     

Spike coding from the perspective of a neurone

In this paper, we compare existing methods for quantifying the coding capacity of a spike train, and review recent developments in the application of information theory to neural coding. We present novel methods for characterising single-unit activity based on the perspective of a downstream neurone and propose a simple yet universally applicable framework to characterise the order of complexity of neural coding by single units. We establish four orders of complexity in the capacity for neural coding. First-order coding, quantified by firing rates, is conveyed by frequencies and is thus entirely described by first moment processes. Second-order coding, represented by the variability of interspike intervals, is quantified by the log interval entropy. Third-order coding is the result of spike motifs that associate adjacent inter-spike intervals beyond chance levels; it is described by the joint interval histogram, and is measured by the mutual information between adjacent log intervals. Finally, nonstationarities in activity represent coding of the fourth-order that arise from the effects of a known or unknown stimulus.     

Reading skill and the identification of words in discourse context

Word identification latencies and word prediction accuracy were compared for groups of skilled and less skilled young readers in three experiments. In each experiment, discourse context reduced identification latencies for less skilled as well as skilled readers. This was true both when context was heard and when it was read. The general relationship between word predictability and latency was the same for skilled readers and for less skilled readers, but only less skilled readers’ identification latencies were affected by word length and word frequency when the word appeared in context. When subjects predicted the word before identifying it, correctly predicted words were identified more quickly than words not predicted correctly, and skilled readers were more accurate in prediction than were less skilled readers. Although reading-related differences in the use of discourse context may characterize other aspects of reading comprehension, the use of context in identifying words is not a major source of reading difficulty.     

Discrimination and production of English vowels by bilingual speakers of Spanish and English

The goal of this study was to examine whether listeners bilingual in Spanish and English would have difficulty in the discrimination of English vowel contrasts. An additional goal was to estimate the correlation between their discrimination and production of these vowels. Participants (40 bilingual Spanish- and English-speaking and 40 native monolingual English-speaking college students, 23-36 years of age) participated (M age = 25.3 yr., Mdn = 25.0). The discrimination and production of English vowels in real and novel words by adult participants bilingual in Spanish and English were examined and their discrimination was compared with that of 40 native monolingual English-speaking participants. Stimuli were presented within triads in an ABX paradigm. Novel words were chosen to represent new words when learning a new language and to provide a more valid test of discrimination. Bilingual participants' productions of vowels were judged by two independent listeners to estimate the correlation between discrimination and production. Discrimination accuracy was significantly greater for native English-speaking participants than for bilingual participants for vowel contrasts and novel words. Significant errors also appeared in the bilingual participants' productions of certain vowels. Earlier age of acquisition, absence of communication problems, and greater percentage of time devoted to communication contributed to greater accuracy in discrimination and production.     

Personal self and collective self: when academic choices depend on the context of social comparison

This research examines the impact of same-sex versus opposite-sex social comparisons on the perception of one’s own abilities at school and subsequent reported marks and academic choices. During their final year, male and female high school students were asked to describe themselves either in comparison with boys in their class, in comparison with girls in their class or without any explicit social comparison (control group). The interaction effects of gender and comparison context on academic selfconcept, school marks and academic choices indicated that gender differences depend on the comparison context. Particularly, as predicted, gender differences disappeared in the same-sex social comparison condition, and even became inverted for the intended academic choices. Here, boys intended to choose more than girls Preparatory Courses for Higher Education (PCHE) in the opposite-sex social comparison condition, while girls more often chose a prestigious PCHE than boys in the same-sex social comparison condition. The theoretical, methodological and practical implications of these findings are discussed.     

Risky economic choices and frontal EEG asymmetry in the context of Reinforcer-Sensitivity-Theory-5

This study investigated individual risky choice behavior in a gambling task and its relation with traits proposed by the Reinforcer-Sensitivity-Theory-5 (RST-5; Corr & McNaughton in Neuroscience and Biobehavioral Reviews, 36(10), 2339–2354, 2012) as well as with frontal EEG asymmetry. As assumed by the RST-5, the results showed independent influences of approach/avoidance and gain/loss sensitivities on participants’ behavior in risky choices. Individual approach/avoidance sensitivity was predicted by trait measures of the behavioral approach system (BAS) and the behavioral inhibition system (BIS), while no such correlation was present for gain/loss sensitivity. EEG recordings revealed relatively stronger left-frontal cortical activity for trials with approach motivation compared to conflict and avoidance motivation. On the individual level, relatively stronger left-frontal cortical activity was associated with trait BAS. In addition, activity changes in frontal EEG asymmetry were associated relatively higher behavioral approach sensitivity. We conclude that frontal EEG asymmetry is an especially useful neuronal marker of BAS sensitivity and that the traits proposed by the RST-5 (measured by frontal EEG asymmetry and self-report) can be used to explain individual differences in risky choice behavior.     

Perceptual scaling of voice identity: common dimensions for different vowels and speakers

The aims of our study were: (1) to determine if the acoustical parameters used by normal subjects to discriminate between different speakers vary when comparisons are made between pairs of two of the same or different vowels, and if they are different for male and female voices; (2) to ask whether individual voices can reasonably be represented as points in a low-dimensional perceptual space such that similarly sounding voices are located close to one another. Subjects were presented with pairs of voices from 16 male and 16 female speakers uttering the three French vowels “a”, “i” and “u” and asked to give speaker similarity judgments. Multidimensional analyses of the similarity matrices were performed separately for male and female voices and for three types of comparisons: same vowels, different vowels and overall average. The resulting dimensions were then interpreted a posteriori in terms of relevant acoustical measures. For both male and female voices, a two-dimensional perceptual space was found to be most appropriate, with axes largely corresponding to contributions of the larynx (pitch) and supra-laryngeal vocal tract (formants), mirroring the two largely independent components of source and filter in voice production. These perceptual spaces of male and female voices and their corresponding voice samples are available at: section Resources.     

Change of perspective in discourse comprehension: encoding and retrieval processes after brain injury

Damage to frontal areas has been associated with nonaphasic language disturbances in which word and sentence level processes remain largely intact but text level processes are impaired. Most studies providing evidence for these language deficits have concentrated on text production. To study text comprehension of nonaphasic patients, we adopted the paradigm of Anderson and Pichert (1978) that was developed to separate encoding from retrieval processes. Subjects read a story under one of two alternative perspectives and subsequently recalled it. After this first recall, they were instructed to now adopt the second perspective and to recall the story once more. Twenty-four brain-injured patients participated. Each patient's lesion was evaluated with respect to the involvement of right- and/or left-frontal regions. Seven patients showed unilateral left-frontal lesions, five patients unilateral right-frontal lesions, four patients had bilateral frontal damage, and the lesions of the remaining eight patients did not involve frontal areas. The only factor predicting behavioral results was the presence of a left-frontal lesion. For patients without frontal lesions and patients with unilateral right-frontal lesions, we replicated previously reported results. Encoding relevant information was recalled better than other information. Furthermore, the switch of perspective aided recall of perspective relevant information during the second recall. In contrast, patients with left-frontal or bilateral frontal lesions could not make use of the perspective instructions. While they showed comparable recall performance, as well as sensitivity to the relative ease of information, neither the encoding instructions nor the switch instructions had an impact on the recall patterns. These results suggest that left-frontal damage leads to an impairment of goal directed text processing skills.     

Cues, consequences and therapeutic talk: effects of social context and coping statements on pain

The present study examined the effects of two types of coping statements on tolerance of experimentally-induced pain when the Ss either thought the experimenter knew or did not know their statements. When Ss thought no one knew their statements, no therapeutic effects were shown. When Ss knew the experimenter knew the statements, the Ss tolerated the pain longer and showed specific effects depending on the specific type of coping statement used. The implications of this study for distinguishing informational, self-instructional and social-motivation effects in therapy are discussed.     

Hemispheric contributions to lexical ambiguity resolution in a discourse context: evidence from individuals with unilateral left and right hemisphere lesions

In the present study, a cross-modal semantic priming task was used to investigate the ability of left-hemisphere-damaged (LHD) nonfluent aphasic, right-hemisphere-damaged (RHD) and non-brain-damaged (NBD) control subjects to use a discourse context to resolve lexically ambiguous words. Subjects first heard four-sentence discourse passages ending in ambiguous words and after an inter-stimulus interval (ISI) of either 0 or 750 ms, made lexical decisions on first- or second-meaning related visual targets. NBD control subjects, at the 0 ms ISI, only activated contextually appropriate meanings, though significant effects, as a group, were only seen in second-meaning biased contexts. Surprisingly, at the 750 ms ISI, these subjects activated both appropriate and inappropriate meanings in first-meaning biased contexts. With respect to the LHD nonfluent aphasic patients, the majority activated first meanings regardless of context at the 0 ms ISI, though effects for the group were not significant. At the 750 ms ISI, these patients again activated first meanings regardless of context, with significant effects for the group only seen in first-meaning biased contexts. With regard to the RHD patients, the majority activated second meanings regardless of context at the 0 ms ISI and first meanings regardless of context at the 750 ms ISI, though, as a group, the effects were not significant. In light of our previous findings (Grindrod & Baum, 2003, submitted), the present data are interpreted as supporting the notion that damage to the left hemisphere disrupts either lexical access processes or the time course of lexical activation, whereas damage to the right hemisphere impairs the use of context and leads to activation of ambiguous word meanings based on meaning frequency.     

Speech production and the predictability of words in context

The purpose of the experiments was to examine the function of hesitation pauses in speech. Pauses were conceived of as anticipating increase of information in subsequent speech and as involving acts of choice.

This hypothesis was tested by relating the incidence of pauses within sentences to the transition probabilities of the words constituting them. Estimates of these probabilities were obtained experimentally by an adaptation of Shannon's guessing technique and were based on reverse as well as forward guessing. The hypothesis was borne out by the facts; hesitancy in speech was shown to be closely related to uncertainty of prediction (entropy) and fluency of utterance to redundancy. These results are shown to be in line with the facts of language statistics. Their theoretical implications for the concept of information and for understanding the processes of speech organization is discussed.     

Global justice in the context of transnational surrogacy: an African bioethical perspective

Theoretical Medicine and Bioethics - The ongoing debate on how best to regulate international commercial surrogacy defies consensus, as the most cogent normative and jurisprudential...     

Contrasting five different theories of letter position coding: evidence from orthographic similarity effects

Five theories of how letter position is coded are contrasted: position-specific slot-coding, Wickelcoding, open-bigram coding (discrete and continuous), and spatial coding. These theories make different predictions regarding the relative similarity of three different types of pairs of letter strings: substitution neighbors, neighbors-once-removed, and double-substitution neighbors. In Experiment 1, we used an illusory word paradigm and found that neighbor-once-removed similarity contexts resulted in fewer illusory word reports than substitution neighbors but more illusory words than double-substitution neighbors. In Experiments 2 and 3, we used a masked form priming technique with a lexical-decision task. The pattern of facilitation was as predicted by spatial coding but was incompatible with slot-coding, Wickelcoding, and both versions of open-bigram coding. These results provide further support for the SOLAR (self-organizing lexical aquisition and recognition) model of visual word identification.     

Distinguishing the time course of lexical and discourse processes through context, coreference, and quantified expressions

How does prior context influence lexical and discourse-level processing during real-time language comprehension? Experiment 1 examined whether the referential ambiguity introduced by a repeated, anaphoric expression had an immediate or delayed effect on lexical and discourse processing, using an eye-tracking-while-reading task. Eye movements indicated facilitated recognition of repeated expressions, suggesting that prior context can rapidly influence lexical processing. However, context effects at the discourse level affected later processing, appearing in longer regression-path durations 2 words after the anaphor and in greater rereading times of the antecedent expression. Experiments 2 and 3 explored the nature of this delay by examining the role of the preceding context in activating relevant representations. Offline and online interpretations confirmed that relevant referents were activated following the critical context. Nevertheless, their initial unavailability during comprehension suggests a robust temporal division between lexical and discourse-level processing.     

Vibrotactile magnitude production scaling: A method for studying sensory-perceptual responses of stutterers and fluent speakers

The method of vibrotactile mangitude production scaling was used to determine the tactile sensory-perceptual integrity for the dorsum of the tongue and thenar eminence of the right hand for 10 fluent speakers and 10 stutterers. It was discovered that both groups performed the task in a similar manner for the thenar eminence of the hand (a nonoral structure) but in a dissimilar manner for the tongue (an oral structure). From these data, it is suggested that the stutterers may maintain a different internal sensory-perceptual process for the tactile system involved in the speech process. The possibility exists that stuttering, for some, may be an “internal disorder” of the tactile-proprioceptive feedback mechanism that is directly involved in speech production.     

Studies in dialogue and discourse: II. Types of discourse initiated by and sustained through questioning

A sociolinguistic approach to the study of language is described. Three types of discourse are defined empirically, each of them initiated and sustained by questions. It is provosed that these types are linguistic expressions or “realizations” of authority relationships between speakers. In the first, Chaining, a conversation is extended through successive questions by the initial questioner; in the second, Arching, it is extended by the respondent's questions; in the third, Embedding, there are two responses to the question. The general hypothesis about the relationship of the linguistic structure of discourse to differentials between speakers in power and authority is examined through an analysis of natural conversations in first-grade classrooms. The findings provide consistent support for this hypothesis. When adults initiate a conversation with a question, they retain control over its course by successive questioning, i.e., by Chaining: when children ask an adult a question, the adult regains control by responding with a question, i.e., by Arching. Children question each other through a more balanced use of Chaining and Arching that might be thought of as either more egalitarian or more competitive.     

The role of discourse context in developing word form representations: a paradoxical relation between reading and learning

To acquire representations of printed words, children must attend to the written form of a word and link this form with the word's pronunciation. When words are read in context, they may be read with less attention to these features, and this can lead to poorer word form retention. Two experiments with young children (ages 5-8 years) confirmed this hypothesis. In our experiments, children attempted to read words they could not previously read, during a self-teaching period, either in context or in isolation. Later they were tested on how well they learned the words as a function of self-teaching condition (isolation or context). Consistent with previous research, children read more words accurately in context than in isolation during self-teaching; however, children had better retention for words learned in isolation. Furthermore, this benefit from learning in isolation was larger for less skilled readers. This effect of poorer word retention when words are learned in context is paradoxical because context has been shown to facilitate word identification. We discuss factors that may influence this effect of context, especially the role of children's skill level and the demands of learning new word representations at the beginning of reading instruction.     

Lexicons, contexts, events, and images: commentary on Elman (2009) from the perspective of dual coding theory

Elman (2009) proposed that the traditional role of the mental lexicon in language processing can largely be replaced by a theoretical model of schematic event knowledge founded on dynamic context-dependent variables. We evaluate Elman's approach and propose an alternative view, based on dual coding theory and evidence that modality-specific cognitive representations contribute strongly to word meaning and language performance across diverse contexts which also have effects predictable from dual coding theory.