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Enhanced extrastriate activation during observation of distorted finger postures.

Hand and finger postures of other people are important body language cues that strongly contribute to the observer's decision about the person's intentions, thoughts, and attentional state. We compared neuromagnetic cortical activation elicited by color images of natural and distorted finger postures. The distorted postures contained computer-deformed joint angles and thereby easily caught the observer's attention. From about 260 msec onwards, extrastriate occipital areas of both hemispheres were activated more strongly by distorted than natural finger postures. We interpret this result as an early top-down effect of emotional valence on the processing of unusual hand shapes in the extrastriate visual cortex.

Adult↗

Connectionism and developmental psychology.

What features of brain processing and neural development support linguistic and cognitive development in young children? To what extent are the profile and timing of development in young children determined by a preordained genetic programme? Does the environment play a crucial role in determining the patterns of change observed in children growing up? These questions have been of central concern to developmental psychologists for well over a century. Yet none of them have received answers that are generally accepted by the profession. This article reviews some recent computational modelling of developmental change in children that promises to contribute to a deeper understanding of the issues behind these questions. The modelling work exploits artificial neural networks that mimic some of the basic properties of neural processing in the brain. These networks involve densely connected webs of simple processing units that propagate and transform complex patterns of activity. When exposed to a training environment, they undergo a process of self-organisation, yielding information processing systems that support new forms of behaviour. The study of the dynamics of these systems and their learning capabilities promises to provide us with important clues as to the nature of the mechanisms underlying development in infants and young children.

Brain↗

Dynamic auditory processing, musical experience and language development.

Children with language-learning impairments (LLI) form a heterogeneous population with the majority having both spoken and written language deficits as well as sensorimotor deficits, specifically those related to dynamic processing. Research has focused on whether or not sensorimotor deficits, specifically auditory spectrotemporal processing deficits, cause phonological deficit, leading to language and reading impairments. New trends aimed at resolving this question include prospective longitudinal studies of genetically at-risk infants, electrophysiological and neuroimaging studies, and studies aimed at evaluating the effects of auditory training (including musical training) on brain organization for language. Better understanding of the origins of developmental LLI will advance our understanding of the neurobiological mechanisms underlying individual differences in language development and lead to more effective educational and intervention strategies. This review is part of the INMED/TINS special issue "Nature and nurture in brain development and neurological disorders", based on presentations at the annual INMED/TINS symposium (http://inmednet.com/).

Auditory Perception↗

Speech phones are a replication code.

Our ability to map sound into pronunciation--vocal imitation--is necessary for vocabulary learning, and so the existence of language. It is also unexplained. Here I show that speech is imitable due because of the brain's use of the innate sensitivities of the vertebrate auditory system for speech motor targets. Their public nature enables speech to transmit articulation information. These units I suggest closely link with phones, the minimal unit of speech segmentation. The conjecture that phones function as a replicative code removes five unexplained anomalies in language science: (i) why nearly eight hundred phones exist but any language uses only a tiny subset of them (evolutionarily this makes no sense); (ii) why newborn infants hear phones of all languages; (iii) why animals also hear them; (iv) why the Wernicke's and Broca's areas arose from homologous areas in primates which process imitation, and why (v) in humans these areas process nonspeech imitation.

Animals↗

Normativity in 18th century discourse on speech.

Eighteenth century phoneticians, such as Dodart, Ferrein, and Hellwag, extended the taxonomy of visible articulatory processes into the realm of the invisible, notably with the exploration of the voicing mechanism. Remedial initiatives were not simply confined to consideration of the outward manifestations of speech and its disorders: The work of Haller, Kuestner, and Morgagni shows an acute awareness of the nervous organization underlying verbal behavior. There was a characteristic preoccupation with mechanical models of speech, which led to the attempts of Kempelen and other investigators to construct actual "speaking machines." Eighteenth century scholars regarded language as not only an innate capacity peculiar to human nature, but also as a bodily habit learned by experience. The function of the orthoepist was to teach the right speech habits, and the upward mobility of the bourgeoisie created a demand for his services.

Europe↗

Understanding 'not': neuropsychological dissociations between hand and head markers of negation in BSL.

Simple negation in natural languages represents a complex interrelationship of syntax, prosody, semantics and pragmatics, and may be realised in various ways: lexically, morphologically and prosodically. In almost all spoken languages, the first two of these are the primary realisations of syntactic negation. In contrast, in many signed languages negation can occur without lexical or morphological marking. Thus, in British Sign Language (BSL), negation is obligatorily expressed using face-head actions alone (facial negation) with the option of articulating a manual form alongside the required face-head actions (lexical negation). What are the processes underlying facial negation? Here, we explore this question neuropsychologically. If facial negation reflects lexico-syntactic processing in BSL, it may be relatively spared in people with unilateral right hemisphere (RH) lesions, as has been suggested for other 'grammatical facial actions' [Language and Speech 42 (1999) 307; Emmorey, K. (2002). Language, cognition and the brain: Insights from sign language research. Mahwah, NJ: Erlbaum (Lawrence)]. Three BSL users with RH lesions were specifically impaired in perceiving facial compared with manual (lexical and morphological) negation. This dissociation was absent in three users of BSL with left hemisphere lesions and different degrees of language disorder, who also showed relative sparing of negation comprehension. We conclude that, in contrast to some analyses [Applied Psycholinguistics 18 (1997) 411; Emmorey, K. (2002). Language, cognition and the brain: Insights from sign language research. Mahwah, NJ: Erlbaum (Lawrence); Archives of Neurology 36 (1979) 837], non-manual negation in sign may not be a direct surface realisation of syntax [Language and Speech 42 (1999) 143; Language and Speech 42 (1999) 127]. Difficulties with facial negation in the RH-lesion group were associated with specific impairments in processing facial images, including facial expressions. However, they did not reflect generalised 'face-blindness', since the reading of (English) speech patterns from faces was spared in this group. We propose that some aspects of the linguistic analysis of sign language are achieved by prosodic analysis systems (analysis of face and head gestures), which are lateralised to the minor hemisphere.

Aged↗

Implications from factor analysis for central auditory processing disorders.

Central auditory processing disorders among school-age children have been challenging to identify and treat. Many issues remain that need to be resolved. Here, we compare and contrast findings on 331 school-age children who were given two of the more common central auditory processing disorder tests (Staggered Spondaic Word [SSW] Test and the SCAN Screening Test for Auditory Processing Disorders). These results replicate and reinforce many of the psychometric findings reported earlier. The use of factor analysis with these test results was explored. Significantly, two factors emerged, including an auditory binaural separation from competition factor and a monaural low redundancy degradation factor. These findings help us define the nature of processes probed by the SCAN screening test and the SSW test. Furthermore, these findings clarify the use of SSW and SCAN because they showed both SSW Left Competing and Right Competing loading within the same factor, whereas the three subtests on SCAN sorted into two rather than three factors.

Adolescent↗

The perceptual characteristics of voice-hallucinations in deaf people: insights into the nature of subvocal thought and sensory feedback loops.

The study of voice-hallucinations in deaf individuals, who exploit the visuomotor rather than auditory modality for communication, provides rare insight into the relationship between sensory experience and how "voices" are perceived. Relatively little is known about the perceptual characteristics of voice-hallucinations in congenitally deaf people who use lip-reading or sign language as their preferred means of communication. The existing literature on hallucinations in deaf people is reviewed, alongside consideration of how such phenomena may fit into explanatory subvocal articulation hypotheses proposed for auditory verbal hallucinations in hearing people. It is suggested that a failure in subvocal articulation processes may account for voice-hallucinations in both hearing and deaf people but that the distinct way in which hallucinations are experienced may be due to differences in a sensory feedback component, which is influenced by both auditory deprivation and language modality. This article highlights how the study of deaf people may inform wider understanding of auditory verbal hallucinations and subvocal processes generally.

Articulation Disorders↗

Cross-cultural research: trying to do it better. 2. Enhancing data quality.

OBJECTIVE: To describe the dilemmas for cross-cultural research in translating study instruments and implementing quality assurance methods, drawing on strategies utilised in the Mothers in a New Country (MINC) Study. METHOD: To translation of study instruments in the MINC Study included: forward and back translations, a bilingual group review process, consultation with bilingual content experts, piloting of different versions of translations, a process for exploring unresolved difficulties and caution in interpreting unusual study findings. Interview quality was assessed by: 1. An ongoing review of interviewer-prepared English coding schedules to ensure completeness of data and identify problems with interview administration. 2. Analysis of fully translated transcripts of six randomly selected early interviews to assess the accuracy and consistency with which questions were asked. 3. A comparison of data sources for 45 randomly selected interviews (original language interview schedules, English coding schedules and translated interview transcripts) to determine the rate and nature of discrepancies. RESULTS: Translation strategies that went beyond simple forward and back translations achieved more reliable and appropriate translations. The complexity of language and cultural differences sometimes still meant less than satisfactory results. Interview tapes played an important quality assurance role, enabling feedback to the interviewers and providing a basis of comparison for identification of data discrepancies. IMPLICATIONS: Ensuring good data quality in cross-cultural research is both critically important and difficult. Open discussion of the problems and concerted efforts to deal with them would benefit future research.

Attitude to Health↗

Natural language from artificial life.

This article aims to show that linguistics, in particular the study of the lexico-syntactic aspects of language, provides fertile ground for artificial life modeling. A survey of the models that have been developed over the last decade and a half is presented to demonstrate that ALife techniques have a lot to offer an explanatory theory of language. It is argued that this is because much of the structure of language is determined by the interaction of three complex adaptive systems: learning, culture, and biological evolution. Computational simulation, informed by theoretical linguistics, is an appropriate response to the challenge of explaining real linguistic data in terms of the processes that underpin human language.

Artificial Intelligence↗

The situated nature of concepts.

For decades the importance of background situations has been documented across all areas of cognition. Nevertheless, theories of concepts generally ignore background situations, focusing largely on bottom-up, stimulus-based processing. Furthermore, empirical research on concepts typically ignores background situations, not incorporating them into experimental designs. A selective review of relevant literatures demonstrates that concepts are not abstracted out of situations but instead are situated. Background situations constrain conceptual processing in many tasks (e.g., recall, recognition, categorization, lexical decision, color naming, property verification, property generation) across many areas of cognition (e.g., episodic memory, conceptual processing, visual object recognition, language comprehension). A taxonomy of situations is proposed in which grain size, meaningfulness, and tangibility distinguish the cumulative situations that structure cognition hierarchically.

Cognition↗

Language impairment in motor neurone disease.

Evidence from recent neuropsychological studies of patients with motor neurone disease (MND) has demonstrated that some patients have cognitive impairment. This challenges traditional teaching that MND is a disease with only motor symptoms. Language processing in MND patients has so far not been studied in any depth, but has only been touched upon as a part of general cognition. This study has assessed nine MND subjects on a range of standardised language assessments and compared their performance to that of nine control subjects. Although this is a small experimental sample of subjects, the results of this study indicate that language impairment is present in some patients with MND. The deficits are subtle and only exposed on formal testing. It is not possible to define the nature of the language impairment from this restricted set of data, but there was evidence of some deficits in a sub-group of MND patients on tasks involving naming, auditory comprehension of complex sentences, some semantic tests and spelling. The implications of these findings are discussed in relationship to the clinical management of patients with MND.

Aged↗

Internal structure of voicing categories in early infancy.

It is well established that young infants process speech in terms of perceptual categories that closely correspond to the phonetic categories of adult language users. Recently, Kuhl (1991) has provided evidence that this correspondence is not limited to the region of category boundaries: At least by 6-7 months of age, vowel categories of infants, like those of adults, have an internal perceptual structure. In the current experiments, which focused on a consonantal contrast, we found evidence of internally structured categories in even younger infants-3-4 months of age. The implications of these findings for the nature of the infant's earliest language-universal categories are discussed, as is the role of exposure to the native language in shaping these categories over the course of development.

Adult↗

Working memory and inference revision in brain-damaged and normally aging adults.

This study examined the association between estimated working memory (WM) capacity and comprehension of passages that required revision of an initial interpretation. Predictions stemmed from the recently elaborated theory of capacity-constrained comprehension (Just & Carpenter, 1992, Psychological Review, 99, 122-149), which includes as a major feature the principle that WM influences comprehension only as processing demands approach or exceed the limits of capacity. As anticipated from task analysis, correlations between unilaterally brain-damaged patients' estimated WM capacity and discourse comprehension performance were minimal for nondemanding measures, and increased in magnitude with task processing requirements. Most notably, a meaningful correlation (/r/ greater than .50) emerged only for the task judged to involve the most demanding comprehension processes, for adults with right hemisphere brain damage. No meaningful associations between estimated WM capacity and task performance were observed for normally aging subjects, who were not expected to have difficulty with any of our comprehension measures. The nature of WM deficits in brain-damaged adults (total capacity, vs. resource allocation, vs. slow or otherwise faulty component processing operations) is considered, and some existing work is interpreted from a cognitive resource perspective. Theoretical implications and clinical applicability of the working memory/resource framework are also discussed.

Aged↗

Sentence processing deficits: a replication of therapy.

This paper describes the replication of a therapeutic programme originally used by one of the authors, Byng (Cognitive Neuropsychology, 1988, 5, 629-676) to remediate a specific sentence processing deficit. Our patient is shown to have similar although not identical deficits to those of one of the patients (JG) described in that programme. Sentence comprehension and production both improved as a result of therapy. The pattern of results observed gave further insights into both the nature of the patient's deficit and the mechanism of therapy.

Aged↗

The human mind: building bridges between neuroscience and psychiatry.

This essay proposes the existence of four unique behavioral characteristics that distinguish Homo sapiens from its nearest evolutionary kin, the great apes. These are inventiveness, capacity for language, curiosity, and self-reflection or self-analysis. Some would counterargue that none of these features are "unique" to humans. Examples would be given of animal "intelligence" involving at times surprising problem-solving abilities. Even "conversations" between humans and parrots might be cited. However, this is to misunderstand what the focus is in the article. This is not a thesis on the continuity or discontinuities of evolution. Every well-trained biologist learns about evolution and understands that the most complex human traits have some hint of related traits in nearest relatives. Rather, the emphasis of this article has been to select and emphasize certain distinctive aspects of human behavior that are the most important features distinguishing human "uniqueness." Uniqueness may be quantified by the number and complexity of processes within the four attributes presented in this article. While this may be an interesting mathematical exercise, the author would rather take it for granted that the outcome would be that humans are significantly more complex in each of the four features referred to than the great apes. For those in the mental health field, one would hope that this overview of the most highly evolved systems in human brain may provide a useful framework where creative therapeutic processes can be applied to the ultimate beneficiary, the client or patient. This article proposes that psychosis can be considered the impossibility of conflict resolution among the special neuronal assemblies that separately mediate feelings of attachment versus abandonment, security versus anxiety, calmness versus anger, fulfillment versus helplessness, and satisfaction of sexual needs. Given this model, the role of the therapist is to consider whether the client is in touch with the various equilibrium points in their current life situation or crisis. A questionnaire designed to help access information on these internal states may work better than an oral interview because it forces the client to reflect. How much conflict does the client feel in sorting out personal priorities? Does the client have any practice at resolving internal conflicts? If unpracticed, is the client likely to act out in destructive ways to self or others to resolve the pressure of internal conflicts? I am sure that we can all think of current well-publicized destructive acts in which one has to wonder precisely what model of mind the psychotherapists were using to assist the client. At a higher level, each human has the potential to be creative. Whether expressed as curiosity about the universe and nature or inventiveness, as in improving the quality of one's life or by the use of gifted language as in art and music, the therapist needs to determine how to assist the client into these kinds of self-defined fulfillments, which one hopes will reduce the other tensions of conflict resolution. There is no doubt that the journey for both the client and therapist will be challenging. Ultimately, the journey is the reward for both the client and therapist. In closing, the following quotation seems appropriate. Sydney Brenner (2002), a pioneer in molecular biology, reviewed a current book on the Science, Politics, and Ethics of the Human Genome Project (Sulston and Ferry 2002). He states, "What I found interesting in the account is that Sulston doesn't tell us anything about the genomes he has sequenced. What did he find there that excited him? What did he learn about genes, about life, about evolution, about worlds to come? It is the play of Hamlet without Hamlet" (p. 794).

Animals↗

Activation of syntactic information during language production.

In order to produce utterances, people must draw upon syntactic information. This paper considers how evidence from syntactic priming experiments casts light upon the nature of syntactic information activation during language production. We examine three issues: the way in which syntactic information is initially activated, the circumstances under which activation may persist or dissipate, and the effects of residual activation of syntactic information on subsequent language production. Evidence from dialog experiments suggests that the information that is initially activated is the same in both production and comprehension. Evidence about the persistence of activation following initial activation is more complex. We suggest that persistence may be related to the potential relevance of the information for subsequent syntactic processing. We show that current evidence is inconclusive about how long syntactic information remains activated.

Cognition↗

Low-birthweight prevention programs: the enigma of failure.

BACKGROUND: Low birthweight is the primary cause of neonatal morbidity and mortality in the United States. The purpose of our study was to identify factors associated with the effectiveness and apparent ineffectiveness of comprehensive, multicomponent, prenatal care programs for preventing low birthweight. METHODS: We reviewed obstetric, pediatric, and public health program evaluations, research reports, and commentaries, published in the English language literature, over the last four decades that pertained to the efficacy of prenatal care for preventing low birthweight. RESULTS: The heterogeneous nature of the services delivered and the lack of consistency in the definition of variables made it impossible to use rigorous, quantitative techniques to summarize this evaluation of the literature. Two general limitations of research design that emerged from our reviews were the focus on clusters of commonly associated risk factors, which has blurred the causal pathways linking specific risk factors to low birthweight, and the failure to examine process variables. These two methodologic problems have led investigators to erroneous conclusions that overstate the significance of negative intervention outcomes. The success and failure of low-birthweight prevention programs has rarely been examined in relation to evidence that the intervention actually modified the targeted risk factors. CONCLUSIONS: Few rigorous evaluations of well-designed programs have been conducted. Without an improvement in intervention designs and evaluation studies, recommendations to support or curtail the funding of comprehensive, multicomponent prenatal care services are inappropriate. Rigorously obtained evidence of the costs and benefits of approaches to the prevention of low birthweight are sorely needed.

Comprehensive Health Care↗