A different form of agraphia: Syntactic writing errors in patients with motor speech and movement disorders

Three patients are described who displayed syntactic writing errors in combination with a motor speech disturbance and impaired motor limb function. Two of the patients had bulbar amyotrophic lateral sclerosis (ALS). Agraphia appeared when verbal communication was no longer possible. Autopsy in one patient disclosed only lesions consistent with ALS. The third patient had palilalia and chorea and, although not aphasic, his written language showed persistent syntactic errors. We hypothesize that the agraphia in these patients occurred because of the combination of disordered feedback from the motor speech apparatus and limbs.     

Syntactic and conversational characteristics of fathers' speech

The verbal interactions of 16 fathers and 16 mothers with their 2-year-olds were assessed during free play. On the basis of the amount of time the father spent with his child weekly, fathers were divided into two groups, those spending a high proportion of time and those spending a low proportion of time. Each parent's speech was coded for a number of syntactic and conversational features. No differences were found between fathers and mothers in the use of these features. Furthermore, the results suggest that the amount of time fathers spend with their children does not dramatically affect the syntactic or conversational features of their speech, since the two groups of fathers did not differ for these features.This research was based on a dissertation submitted to the Pennsylvania State University in partial fulfillment of the requirements for the Ph.D.     

Syntactic structure and acoustic pattern in speech perception Arthur Wingfield

The interaction of syntactic structure and acoustic pattern in perceptual segmentation of heard speech was investigated using sentences recorded with intonation patterns appropriate to their underlying structure and sentences where intonation was placed in direct conflict with the underlying structure. Speech samples were monitored through dichotic earphones with messages switched from one ear to the other either between or within major linguistic constituents. Analysis of errors in source localization and in sentence reproduction suggested a primary role of acoustic pattern in segmentation is to cue underlying syntactic structure. Two subsidiary experiments provided evidence that observed effects were related to active perceptual processing of the speech signal.     

Syntactic structure modifies attention during speech perception and recognition

The present paper demonstrates the interaction of syntactic structure and speech perception with a response task which minimizes the effects of memory: reaction time (RT) to clicks during sentences. (1) In 12-word unfamiliar sentences each with two clauses, RT is relatively slow overall to clicks located at the end of the first clause but decreases as a function of clause length. Clicks at the beginning of the second clause are not affected by length of the preceding clause. (2) In familiar sentences, RT is relatively fast to clicks located at the end of a clause while RT to clicks at the beginning of clauses is relatively unaffected by familiarity. (3) RT is not fastest overall to clicks located between clauses either in novel or familiar sentences. (4) As in previous studies, the subject's subsequent judegment of the location of the click tone are towards the clause break. (5) We could find no systematic interaction between RT and subjective click location. Findings (1) to (3) are consistent with the view that perceptual processing alternates between attending to all external stimuli and developing an internal representation of the stimuli. Finding (3) is in conflict with an “information channel” view of immediate attention to speech, which would predict high sensory attention to non-speech stimuli between clauses. However, findings (4) and (5) indicate that the channel view of perception may be correct for that perceptual processing which occurs after the immediate organization of the speech stimulus into major segments.     

Constraints upon word substitution speech errors

We explore the features of a corpus of naturally occurring word substitution speech errors. Words are replaced by more imageable competitors in semantic substitution errors but not in phonological substitution errors. Frequency effects in these errors are complex and the details prove difficult for any model of speech production. We argue that word frequency mainly affects phonological errors. Both semantic and phonological substitutions are constrained by phonological and syntactic similarity between the target and intrusion. We distinguish between associative and shared-feature semantic substitutions. Associative errors originate from outside the lexicon, while shared-feature errors arise within the lexicon and occur when particular properties of the targets make them less accessible than the intrusion. Semantic errors arise early while accessing lemmas from a semantic-conceptual input, while phonological errors arise late when accessing phonological forms from lemmas. Semantic errors are primarily sensitive to the properties of the semantic field involved, whereas phonological errors are sensitive to phonological properties of the targets and intrusions.     

Dynamic action units slip in speech production errors

In the past, the nature of the compositional units proposed for spoken language has largely diverged from the types of control units pursued in the domains of other skilled motor tasks. A classic source of evidence as to the units structuring speech has been patterns observed in speech errors--"slips of the tongue". The present study reports, for the first time, on kinematic data from tongue and lip movements during speech errors elicited in the laboratory using a repetition task. Our data are consistent with the hypothesis that speech production results from the assembly of dynamically defined action units--gestures--in a linguistically structured environment. The experimental results support both the presence of gestural units and the dynamical properties of these units and their coordination. This study of speech articulation shows that it is possible to develop a principled account of spoken language within a more general theory of action.     

Effects of verb complexity on speech errors

Two experiments examined whether semantically related verbs that contrast with respect to the absence versus the presence of an additional semantic feature differentially compete for selection during the encoding of a sentence for production. In both experiments, a speech error induction task was used to elicit contextual (misordering) errors involving semantically related verbs that contrasted only in their semantic complexity or in both their semantic and morphophonological complexity. The prediction was that an asymmetry in contextual errors would be observed in which the more complex verbs would replace the simpler verbs more often than the reverse. This prediction was confirmed in both experiments, with more perseverations and anticipations involving the semantically more complex verb of antonym pairs in Experiment 1, and more perseverations and anticipations involving the semantically more-specified verb of a heavy-light pair in Experiment 2. The implications of the results for spreading-activation theories of language production are discussed.     

Detection of errors during speech production: a review of speech monitoring models

In this paper three theories of speech monitoring are evaluated. The perception-based approach proposes that the same mechanism employed in understanding other-produced language, the speech comprehension system, is also used to monitor one's own speech production. A conceptual, an inner, and an auditory loop convey information to a central, conscious monitor which scrutinizes the adequacy of the ongoing speech flow. In this model, only the end-products in the speech production sequences, the preverbal (propositional) message, the phonetic plan, and the auditory results, are verified. The production-based account assumes multiple local, autonomous monitoring devices, which can look inside formulation components. Moreover, these devices might be tuned to various signals from the actual speech motor execution, e.g. efferent, tactile, and proprioceptive feedback. Finally, node structure theory views error detection as a natural outflow of the activation patterns in the node system for speech production. Errors result in prolonged activation of uncommitted nodes, which in turn may incite error awareness. The approaches differ on the points of consciousness, volition and control, the number of monitoring channels, and their speed, flexibility, and capacity, and whether they can account for concurrent language comprehension disorders. From the empirical evidence presently available, it is argued for a central perception-based monitor, potentially augmented with a few automatic, production-based error detection devices.     

Representation of serial order in speech: evidence from the repeated phoneme effect in speech errors

Previous research has shown that slips of the tongue involving the exchange of phonemes (e.g., left hemisphere----left hemisphere) are often characterized by a repeated phoneme next to the exchanging ones (the vowel /epsilon/ in the above example is next to both of the exchanging sounds, /l/ and /h/). Two experiments, which elicited slips of the tongue under controlled conditions, revealed that repeated sounds in a speech plan are contributory causes of phoneme exchanges, anticipations, and perseverations. In addition, it was found that repeated sounds induce the misordering of sounds that are not adjacent to the repeated ones, as well as those that are adjacent to the repeated ones. An analysis of a collection of natural slips also supported the conclusion that repeated sounds cause nonadjacent sounds to slip. The results are seen as inconsistent with serial order theories that propose a linear structure of sounds held together by contextual influences between adjacent phonemes.     

Syntactic determinants of stuttering in the spontaneous speech of normally fluent and stuttering children

Conflicting findings have been reported concerning whether fluent children use more complex syntactic structures than stutterers and whether or not stutterers experience specific difficulty with complex syntactic structures. On critical examination, the first of these apparent discrepancies appears to be due to (a) differences in the methods employed for syntactic analysis in different studies, and (b) misleading impressions gained by looking at speakers within a single age range. Data were reanalyzed where one method of analysis had shown that fluent speakers and stutterers did not differ with regard to syntactic structures used but where they did show a propensity for stuttering to occur on complex syntactic structures. These data cover a range of age groups. When the second method of syntactic analysis was applied, a difference was found between fluent speakers and stutterers, with the stutterers initially using more simple structures and fewer complex ones. This difference decreased over age groups. However, a difference still remained with respect to which syntactic structures stutterers experience difficulty. An additional analysis, not formerly conducted on these data, showed that, as reported elsewhere, there was a higher probability of stuttering on clause-initial and. It was also shown that this tendency decreased with age group of the stutterers.     

Interaction and representational integration: evidence from speech errors

We examine the mechanisms that support interaction between lexical, phonological and phonetic processes during language production. Studies of the phonetics of speech errors have provided evidence that partially activated lexical and phonological representations influence phonetic processing. We examine how these interactive effects are modulated by lexical frequency. Previous research has demonstrated that during lexical access, the processing of high frequency words is facilitated; in contrast, during phonetic encoding, the properties of low frequency words are enhanced. These contrasting effects provide the opportunity to distinguish two theoretical perspectives on how interaction between processing levels can be increased. A theory in which cascading activation is used to increase interaction predicts that the facilitation of high frequency words will enhance their influence on the phonetic properties of speech errors. Alternatively, if interaction is increased by integrating levels of representation, the phonetics of speech errors will reflect the retrieval of enhanced phonetic properties for low frequency words. Utilizing a novel statistical analysis method, we show that in experimentally induced speech errors low lexical frequency targets and outcomes exhibit enhanced phonetic processing. We sketch an interactive model of lexical, phonological and phonetic processing that accounts for the conflicting effects of lexical frequency on lexical access and phonetic processing.     

A critique of top-down independent levels models of speech production: Evidence from non-plan-internal speech errors

A number of speech errors are examined which are difficult to account for by top-down serial processing models of speech production which hove independent levels of processing. In particular, most of these errors are characterized by the presence of an interfering element which is external to the utterance under current construction. This paper has two main aims: to classify these errors, and to examine the constraints upon them. It is found that phonological similarity between the target and intrusion is a major determinant of error occurrence. The consequences for models of speech production are discussed in a framework consisting of the architecture and control structure of those models. A particular model to account for these data is proposed, consisting of a spreading activation lexical network.     

Feature migration in time: reflection of selective attention on speech errors

This article describes an initial study of the effect of focused attention on phonological speech errors. In 3 experiments, participants recited 4-word tongue twisters and focused attention on 1 (or none) of the words. The attended word was singled out differently in each experiment; participants were under instructions to avoid errors on the attended word, to stress it, or to say it silently. The experiments showed that all methods of attending to a word decreased errors on that word, while increasing errors on the surrounding words. However, this error increase did not result from a relative increase in phonemic migrations originating from the attended word. This pattern is inconsistent with conceptualizing attention either as a higher activation of the attended word or greater inhibition of the unattended words throughout the production of the sequence. Instead, it is consistent with a model that presumes that attention exerts its effect at the time of production of the attended word, without lingering effects on the past or the future.     

Sequencing, speech production, and selective effects of aging on phonological and morphological speech errors

To test age-linked predictions of node structure theory (NST) and other theories, young and older adults performed a task that elicited large numbers of phonological and morphological speech errors. Stimuli were visually presented words containing either /p/ or /b/, and participants changed the /p/ to /b/ or vice versa and produced the resulting word as quickly as possible. For example, the correct response was "bunk" for the stimulus PUNK, and "ripped" for RIBBED. Consistent with NST predictions, the elicited speech errors exhibited selective effects of aging. Some error types decreased with aging. For example, young adults produced more nonsequential substitution errors (as a percentage of total errors) than older adults (e.g., intended bills misproduced as "gills"). However, other error types remained constant or increased with aging. For example, older adults produced more omission errors than young adults, especially omissions involving inflectional endings (e.g. intended ripped misproduced as "np"). In addition, older adults exhibited special difficulties with 2 types of phonological and morphological sequencing processes.     

How scenes containing visual errors affect speech fluency in young and older adults

We compared young and older adults’ speech during an error detection task, with some pictures containing visual errors and anomalies and other pictures error-free. We analyzed three disfluency types: mid-phrase speech fillers (e.g., It’s a little, um, girl), repetitions (e.g., He’s trying to catch the- the birds), and repairs (e.g., She- you can see her legs). Older adults produced more mid-phrase fillers than young adults only when describing pictures containing errors. These often reflect word retrieval problems and represent clear disruptions to fluency, so this interaction indicates that the need to form and maintain representations of novel information can specifically compromise older adults’ speech fluency. Overall, older adults produced more repetitions and repairs than young adults, regardless of picture type, indicating general age-related increases in these disfluencies. The obtained patterns are discussed in the context of the Transmission Deficit Hypothesis and other approaches to age-related changes in speech fluency.     

Syntactic,semantic, and rhythmic influences on children's and adults' motor programming of speech

The influence of linguistic and paralinguistic structure on speech motor programming was investigated for 5-year-olds, 8-year-olds, and adults. Subjects repeated verbal stimuli, each at maximum rate on numerous consecutive trials. It was hypothesized that structure in an utterance would allow a speaker to organize its motor program more efficiently than would be possible for an otherwise identical utterance that lacked such structure, although the types of structure employed might change with age. Differences in the efficiency of motor program organization were expected to be evidenced in the syllable duration and the relative variability of the syllable duration of subjects' repetitions. At all ages, repetition durations were shorter for stimuli with a sentencelike rhythm than for unstructured stimuli. Stimuli that were syntactically structured and contained a sentencelike rhythm were spoken with shorter durations than nonsyntactic stimuli with sentential rhythm but only by 8-year-olds and adults.     

Voice-onset time as a clue to the nature of Broca speech errors

Blumstein, Cooper, Goodglass, Statlender, and Gottleib (Brain and Language, 9, 153–170 (1980)) attempt to determine by an examination of the VOTs of aphasic speakers whether Broca's aphasics make phonemic substitutions in addition to their well-known phonetic errors. There are a number of problems with this study, mostly due to an apparent failure to fully appreciate the fact that VOT is a cover term for several acoustic features. It is suggested that VOT measurement in any given position in a word cannot solve this problem and that future studies should include glottographic observations as well as VOT measurements made in all positions in the word.