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PubMed1982

The role of the gross spectral shape as a perceptual cue to place articulation in initial stop consonants.

This series of studies explored the extent to which the gross shape of the onset spectrum is used by the listener for the identification of place of articulation in initial stop consonants. Synthetic stimuli were generated with onset frequencies appropriate to the syllables [ba bi du da di du] and with the gross shape of the onset spectrum manipulated to be appropriate for either alveolar consonants or labial consonants. Stimuli were presented for identification and discrimination. In addition, adaptation effects of stimuli containing appropriate frequency and shape and incompatible frequency and shape were explored on a place-of-articulation onset continuum. Although identification performance was determined by onset frequency rather than gross shape of the spectrum, presentation of stimuli in which shape was inconsistent with frequency reduced identification performance. Further, subjects could discriminate stimuli which varied only in spectral shape. Finally, significantly less adaptation was found for a [da] onset with a labial spectrum shape than [da] onset with an alveolar spectrum shape. These results suggest that although the invariant properties residing in the gross shape of the onset spectrum may serve as a classificatory framework for the phonetic dimensions of natural language, they may not provide the primary perceptual attributes for place of articulation in ongoing speech processing.

Humans↗
PubMed1975

Natural language storage and retrieval of medical diagnostic information. Experience at the UCLA hospital and clinics over a 10-year period.

A natural language storage and retrieval system initially designed for pathology reports has been in operation for ten years at UCLA Hospital and Clinics. The original system has been improved to provide a thesaurus processor with added capabilities for expanding search request terms and a newly developed set of search programs with user options that make complex and more accurate retrievals possible. Summarized diagnostic statements or impressions from five specialities (Surgical Pathology, Bone Marrow, Autopsy, Nuclear Medicine, and Neuroradiology), are automatically encoded by referencing a master computer dictionary containing a unique numeric code for each English word. Input and retrievals are batch, off-line operations in free text, and are currently processed on the IBM 370/145. User acceptance is high, quality of retrievals improved, and cost is nominal. This paper describes an expanded natural language system which in now providing a viable form of information storage and retrieval for research, medical education, patient care, quality control, statistics and administrative purposes.

California↗
PubMed2003

Studying the grammatical aspects of word recognition: lexical priming, parsing, and syntactic ambiguity resolution.

Two experiments are reported examining the relationship between lexical and syntactic processing during language comprehension, combining techniques common to the on-line study of syntactic ambiguity resolution with priming techniques common to the study of lexical processing. By manipulating grammatical properties of lexical primes, we explore how lexically based knowledge is activated and guides combinatory sentence processing. Particularly, we find that nouns (like verbs, see Trueswell & Kim, 1998) can activate detailed lexically specific syntactic information and that these representations guide the resolution of relevant syntactic ambiguities pertaining to verb argument structure. These findings suggest that certain principles of knowledge representation common to theories of lexical knowledge--such as overlapping and distributed representations--also characterize grammatical knowledge. Additionally, observations from an auditory comprehension study suggest similar conclusions about the lexical nature of parsing in spoken language comprehension. They also suggest that thematic role and syntactic preferences are activated during word recognition and that both influence combinatory processing.

Humans↗
PubMed2006

Acceptance and commitment therapy: model, processes and outcomes.

The present article presents and reviews the model of psychopathology and treatment underlying Acceptance and Commitment Therapy (ACT). ACT is unusual in that it is linked to a comprehensive active basic research program on the nature of human language and cognition (Relational Frame Theory), echoing back to an earlier era of behavior therapy in which clinical treatments were consciously based on basic behavioral principles. The evidence from correlational, component, process of change, and outcome comparisons relevant to the model are broadly supportive, but the literature is not mature and many questions have not yet been examined. What evidence is available suggests that ACT works through different processes than active treatment comparisons, including traditional Cognitive-Behavior Therapy (CBT). There are not enough well-controlled studies to conclude that ACT is generally more effective than other active treatments across the range of problems examined, but so far the data are promising.

Cognitive Behavioral Therapy↗
PubMedDate not supplied

Visual word perception and semantic processing: an electrophysiological perspective.

This paper reports data from three experiments in which semantic priming effects were investigated using the event-related potentials (ERP) technique. In the first experiment, a specific electrophysiological manifestation of semantic priming was demonstrated, and it was related to a previously reported negative component--N400. In the second experiment, it was suggested that the N400 wave does not directly reflect disconfirmation of subjects' expectations, but that it is related to semantic activation and is affected by the amount of lexical processing. In the third experiment, it was demonstrated that priming effects are also evident in natural reading, without any time constraints imposed by the task. It is concluded that the ERP technique provides an important tool in cognitive research in general, and language processing in particular.

Brain↗
PubMed2003

Sounds, words, sentences: age-related changes across levels of language processing.

Age-related changes in sensory, lexical, and sentence processing were examined and compared using event-related potentials (ERPs) recorded as young and elderly participants listened to natural speech for comprehension. Lexically associated and unassociated word pairs were embedded in meaningful or syntactically legal but meaningless sentences. Early, general sensory, and attention-related responses (N1, P2) were delayed by about 25 ms for older participants, but later components indexing semantic processing (N400) were not delayed. There were no differences in the size, timing, or distribution of lexical associative effects for the two groups. In contrast, message-level context effects were delayed by more than 200 ms in the elderly group. The results support models that posit age-related changes primarily in higher order language processes.

Adolescent↗
PubMed2005

Do differences in brain activation challenge universal theories of dyslexia?

It has been commonly agreed that developmental dyslexia in different languages has a common biological origin: a dysfunction of left posterior temporal brain regions dealing with phonological processes. Siok, Perfetti, Jin, and Tan (2004, Nature, 431, 71-76) challenge this biological unity theory of dyslexia: Chinese dyslexics show no deficits in posterior temporal brain regions but a functional disruption of the left middle frontal gyrus. Here, I will argue that these data do not challenge universal cognitive theories of dyslexia according to which weaknesses in the ability to process the phonological features of language are at the origin of dyslexia.

Asian People↗
PubMed1977

[In the boundaries of aphasia].

The anatomical boundaries of those structures whose lesion leads to the disturbances of language are indistintic and largely exceed the classical "areas of language", including subcortical structures as the thalamus and the non-dominant hemisphere. It is equally indistinct the possibility of definition of aphasic disturbances. On one hand aphasia can be seen within the realm of decodification, as a failure of a mental rather than of a verbal process, close to dementia, while among the codification mechanisms motor aphasia can appear a syndrome of phonetic desintegration with component of apraxic, dystonic and paretic nature. Esquizophasia and agrammatism are two examples of those peculiar disturbances of language. The correlation between disturbances of language and of intelligence is another frontier of aphasies where a causal relationship appears to be well established. Aphasias, interpreted in the beginnings as anatomically localized well defined disturbances of function, are now seen both anatomically and functionally, as a process with indistinct and mixed boundarie related to other equally illimited and indistinct functions.

Aphasia↗
PubMed1992

Delay versus deviance in the language acquisition of language-impaired children.

To investigate the issue of delay versus deviance in the language acquisition of language-impaired (LI) children, the order of acquisition of a set of linguistic structures and the relationship obtaining between one structure and another were examined in comprehension and production over a 5-year period in a group of LI and language-matched normal children. The results demonstrated a marked similarity between groups, both in the point at which mastery of individual structures was achieved and in the overall patterns of acquisition demonstrated. These data suggest that LI children are constructing grammars based on the same rules and principles as those of linguistically normal control subjects, and that their linguistic impairments may be principally processing, not representational, in nature.

Child, Preschool↗
PubMedDate not supplied

Adaptive communication systems for patients with mobility disorders.

An adaptive communication system has been developed for individuals with mobility disorders. It uses specialized computer software and hardware that compensate for this disability. For an individual with a motor-control impairment who is not able to use a keyboard effectively, a computer voice-recognition technology now removes this communication barrier. Speech-recognition systems consist of three basic components: speech processing, speech recognition, and speech understanding. The new Dragon Dictate (Dragon Systems, Inc., Newton, Mass.) is the first large-vocabulary speech recognition system in the personal computer industry that interactively learns a user's vocabulary and mode of speaking and responds to natural language rather than to limited sets of words. This speech-recognition system requires a microprocessor, a display monitor, a printer, and specific software packages, including word-processing and enhanced memory-management software. Important considerations in the use of this speech-recognition system include microphone positioning and training of the system. With the advent of this new voice-recognition computer system, another communication barrier between the disabled and society has been overcome.

Communication Devices for People with Disabilities↗
PubMedDate not supplied

Masked priming of prefixes and the influence of spelling-meaning consistency.

Two experiments are reported which examined whether a prefixed word can be primed by a word sharing only the prefix letters in a masked priming paradigm. In addition the studies examined whether the size of the priming effect is influenced by the consistency with which a prefix letter pattern appears in real prefixed words. The ratio of real prefixed words to all words containing a prefix letter pattern was calculated and used to identify high-consistency prefixes, which are frequently used as prefixes (e.g., UN in UNHAPPY) and rarely appear as pseudoprefixes (e.g., UNCLE), and low-consistency prefixes, which appear in many pseudoprefixed words (e.g., DE in DESERT) but fewer truly prefixed words (e.g., DECODE). In Experiment 1, decision latencies for both types of prefixes were facilitated when real prefixed target words were preceded by real prefixed prime words in a short SOA masked priming paradigm, although the size of the priming effect for low-consistency prefixes was similar in size to that for orthographic controls. In Experiment 2, real prefixed target words were preceded by pseudoprefixed prime words. Facilitation in performance remained for high-consistency prefixes but was absent for low-consistency prefixes. These results support models of morphological processing that are sensitive to the statistical nature of the relationships between orthographic and semantic representations in a language.

Decision Making↗
PubMed2006

Evaluation of spoken dialogue technology for real-time health data collection.

BACKGROUND: A real-time assessment of patients' experiences is an important methodology for studies in health care, quality of life, behavioral sciences, and new drug and treatment development. Ecological momentary assessment is a methodology that allows for real-time assessment of experience and behavior in a subject's natural environment. Recently, electronic data collection techniques have been introduced, including systems utilizing interactive voice response. OBJECTIVE: The objective of this project was evaluation of spoken dialogue methodology for real-time data collection of information from patients for health, behavioral, and lifestyle studies and monitoring. While the management of the data collection process was Internet-based, this additional eHealth communication channel was based on over-the-phone natural language conversation with a dialogue system utilizing automated speech recognition technology. For this study we implemented a dialogue system for patients' assessment and monitoring of chronic pain. METHODS: Experimental evaluation of usability of the Pain Monitoring Voice Diary was performed with 24 volunteers. The volunteers were asked to contribute 10 sessions with the system over a period of 2 weeks; in practice, the number of sessions per subject ranged from 1 to 20. The subjects were asked to either relate to pain episodes in their past while answering the system's questions, or use as a guidance one of nine provided medical scenarios compiled by a pain specialist, ranging from migraines and back pain to post-surgical pain (knee injury) and cancer- and chemotherapy-related afflictions. RESULTS: From 24 volunteers, we collected a total of 177 dialogue sessions: 171 sessions were completed, while the caller hung up in the other 6 sessions. There were a total of 2437 dialogue turns, where a dialogue turn corresponds to one system prompt and one user utterance. The data capture rate, measuring the percentage of slots filled automatically, was 98%, while the other 2% were flagged for transcription. Among the utterances sent to transcription, where the user had opted for the "none of those" option, 70% corresponded to the "type of pain" slot, 20% to the "symptoms" slot, and 10% to the "body part" slot, indicating that those are the grammars with the highest out-of-vocabulary rate. CONCLUSIONS: The results of this feasibility study indicated that desired accuracy of data can be achieved with a high degree of automation (98% in the study) and that the users were indeed capable of utilizing the flexible interface, the sessions becoming more and more efficient as users' experience increased, both in terms of session duration and avoidance of troublesome dialogue situations.

Adaptation, Psychological↗
PubMed1989

Dimensional thinking in language impaired children.

This study investigated the dimensional knowledge evidenced by language impaired (LI) preschoolers. Ten LI and 10 language normal (LN) children, aged 3:6 to 5:9, were asked to solve verbal and nonverbal problems requiring color and size judgments. There were no group differences on the verbal task, but the LI children performed less well than the LN children on the nonverbal task. Much of this difference stemmed from their difficulty with size items. The ordinal nature of the size dimension implies greater cognitive processing demands than are inherent in nominal dimensions such as color. Given the known processing limitations of language impaired children, this complexity apparently can lead to erroneous judgment even when requisite knowledge is present. It may also contribute to delays in the initial construction of dimensional knowledge.

Child, Preschool↗
PubMed2006

Putting the technical back into socio-technical systems research.

Socio-technical systems (STS) analysis has provided us with a powerful framework with which to analyse the reasons behind the poor acceptability, uptake and performance of many information or communication technology systems (ICT). However, for the contribution of STS thinking to be more than simply a means of critiquing current practices and ICT systems, it needs to also contribute to the process of developing new and more effective ICT systems. Specifically, we need to develop a formal design language for translating our insights about the socio-technical nature of work, into design specifications that result in better interventions in the work place. We need to get 'technical' about what we mean and about what we want from a design, and we need to work alongside technologists to shape technology, as well as the processes, organisations and cultures within which they will be embedded. Indeed the process of design itself can be seen as a socio-technical one, and understanding the decision to design itself may allow us one day to stop designing for people, and create STS that sustainably design themselves.

Humans↗
PubMed2006

Broca's area and inflectional morphology: evidence from broca's aphasia and computer modeling.

In a series of articles Ullman (2001, 2004; Ullman et al., 1997) has proposed that regular inflection is critically subserved by Broca's area. This suggestion is motivated by the finding that English speaking Broca's aphasics show selective deficits with regular inflection. Here we argue that this proposal does not hold cross-linguistically but is based on a confound between inflectional suffix and regularity that is specific to the English language. We present data from two experimental studies of participle inflection with 13 German and 12 Dutch Broca's aphasics. None of these aphasic speakers are selectively impaired for regular inflection but instead most of them show selective deficits with irregular inflection. These data suggest that a selective regular deficit is not a characteristic of Broca's aphasia across languages, and that Broca's area is not critically involved in regular inflection. To investigate the nature and localization of the processes underlying inflection we present a connectionist neural network model that accounts for the deficits of the German aphasic speakers. The model implements the view that the inflection of all verb types is based on a single mechanism with multiple representations that emerge from experience-dependent brain development. We show that global damage to this model results in a selective deficit for irregular inflection that is comparable to that of the German aphasic speakers. This finding suggests that a selective impairment of irregular participles as observed by German and Dutch aphasic speakers does not presuppose two distinctly localized mechanisms or processes that can be selectively affected by brain damage.

Adult↗
PubMed2002

Form is easy, meaning is hard: resolving a paradox in early child language.

A developmental paradox is discussed: studies of infant processing of language and language-like stimuli indicate considerable ability to abstract patterns over specific items and to distinguish natural from unnatural English sentences. In contrast, studies of toddler language production find little ability to generalize patterns over specific English words or constructions. Thus, infants appear to be abstract auditory or language processors whereas toddlers appear to be non-abstract, item-specific language users. Three resolutions are offered to this paradox. The first, that no resolution is necessary because only the toddler findings come from language use in a communicative context and so only the toddler findings are relevant to linguistic knowledge, is rejected. The second, that the contradictions are rooted in the differing methodologies of the two sets of studies (comprehension vs. production), is found to explain important aspects of the contradictory findings. The third, that the contractions come from the differing content of the stimuli in the studies, is also found to be explanatory and is argued to carry greater weight. Resolution 3 suggests that the patterns that infants extract from their linguistic input are not yet tied to meaning; thus, toddlers do not lose these earlier-abstracted forms but their use of them is limited until they have been integrated with meaning. It is argued that in language acquisition, learning form is easy but learning meaning, and especially linking meanings and forms, is hard.

Child Language↗