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PubMed2001

Attentional selection and the processing of task-irrelevant information: insights from fMRI examinations of the Stroop task.

In this chapter, we discuss our research that reveals how attentional mechanisms can modulate activity of posterior brain regions responsible for processing the unattended attribute of a stimulus. To do so, we utilized fMRI to reveal patterns of regional brain activity for variants of the Stroop task that differ in the nature of the task-irrelevant stimulus attribute. In all variants, individuals had to identify the ink color in which an item was presented. To vary attentional demands, we manipulated whether or not the task-irrelevant information contained conflicting color information. The variants differed in whether the conflicting color information was contained in a word naming a color (e.g. the word 'red' in blue ink), a word naming an object highly associated with a specific color (e.g. the word 'frog' in red ink), or a line drawing of an object highly associated with a specific color (e.g. a drawing of a frog in red ink). When the unattended stimulus attribute contained color information that conflicted with an item's ink color, increased activity was observed in the posterior brain region that processes the aspect of the task-irrelevant attribute related to color. Increased activity was observed in the left precuneus and left superior parietal cortex when the conflicting information arose from a color word; in the middle temporal gyrus and insular cortex when the word named an object highly associated with a specific color, and included extensive regions of early portions of the ventral visual processing stream when a line drawing was highly associated with a specific color. These areas have been implicated in word processing, semantic processing, and visual processing, respectively. Our results suggest that attentional selection can occur by: (1) increasing the gain on all posterior regions responsible for processing information related to the task demands, regardless of whether that information is contained in the task-relevant or task-irrelevant dimension; (2) limiting the processing of task-irrelevant information in order to reduce interference; and (3) modulating the processing of representations varying from those of a low-level perceptual nature up through those of a higher-order semantic nature.

Adult↗
PubMed1979

Personal pronouns and the autistic child.

The long-recognized difficulties of the speaking autistic child with the use and nonuse of personal pronouns ["reversals" and "avoidance"] have been generally attributed either to the nondifferentiation of the self or to the frequently coexisting symptom of echolalia. These explanations are reconsidered in this eclectic analysis from the perspective of current theory and research in development of self and of language. Emphasis is on studies of normal development of personal pronouns and the roles played in that process by listening, echoic memory, mitigated echolalia [recoding], and person deixis. It is concluded that multiple developmental obstacles of a social, cognitive, and grammatical nature underlie the more obvious symptoms and militate against the child's resolution of labels and their referents. Treatment alternatives that de-emphasize the primacy of I are offered.

Autistic Disorder↗
PubMed1991

Standardized and flexible batteries in neuropsychology: an assessment update.

This article summarizes current literature relevant to commonly used tests and test batteries in clinical neuropsychology. The first section contains a discussion of the philosophy and relative advantages of standardized and flexible battery approaches in neuropsychology. The second contains historical background and a literature review of the two major standardized test batteries: the Halstead-Reitan and Luria-Nebraska. The third section includes reviews of tests that are frequently used in the flexible battery approach. Various tests of intellectual functioning, attention, memory, language, and spatial analyses are critiqued in this section. Contributions of the process approach are noted. The article ends by underscoring the need for continued research into the nature of neuropsychological measures and the abilities they assess.

Attention↗
PubMed2005

Functional neuroanatomy of non-verbal semantic sound processing in humans.

Environmental sounds convey specific meanings and the neural circuitry for their recognition may have preceded language. To dissociate semantic mnemonic from sensory perceptual processing of non-verbal sound stimuli we systematically altered the inherent semantic properties of non-verbal sounds from natural and man-made sources while keeping their acoustic characteristics closely matched. We hypothesized that acoustic analysis of complex non-verbal sounds would be right lateralized in auditory cortex regardless of meaning content and that left hemisphere regions would be engaged when meaningful concept could be extracted. Using H(2) (15)O-PET imaging and SPM data analysis, we demonstrated that activation of the left superior temporal and left parahippocampal gyrus along with left inferior frontal regions was specifically associated with listening to meaningful sounds. In contrast, for both types of sounds, acoustic analysis was associated with activation of right auditory cortices. We conclude that left hemisphere brain regions are engaged when sounds are meaningful or intelligible.

Acoustic Stimulation↗
PubMed2006

Beyond the face: exploring rapid influences of context on face processing.

Humans optimize behavior by deriving context-based expectations. Contextual data that are important for survival are extracted rapidly, using coarse information, adaptive decision strategies, and dedicated neural infrastructure. In the field of object perception, the influence of a surrounding context has been a major research theme, and it has generated a large literature. That visual context, as typically provided by natural scenes, facilitates object recognition as has been convincingly demonstrated (Bar, M. (2004) Nat. Rev. Neurosci., 5: 617-629). Just like objects, faces are generally encountered as part of a natural scene. Thus far, the facial expression literature has neglected such context and treats facial expressions as if they stand on their own. This constitutes a major gap in our knowledge. Facial expressions tend to appear in a context of head and body orientations, body movements, posture changes, and other object-related actions with a similar or at least a closely related meaning. For instance, one would expect a frightened face when confronted to an external danger to be at least accompanied by withdrawal movements of head and shoulders. Furthermore, some cues provided by the environment or the context in which a facial expression appears may have a direct relation with the emotion displayed by the face. The brain may even fill in the natural scene context typically associated with the facial expression. Recognition of the facial expression may also profit from processing the vocal emotion as well as the emotional body language that normally accompany it. Here we review the emerging evidence on how the immediate visual and auditory contexts influence the recognition of facial expressions.

Electroencephalography↗
PubMedDate not supplied

Processing of mass/count information in Alzheimer's disease and mild cognitive impairment.

This study examines the processing of a specific linguistic distinction, the mass/count distinction, in patients suffering from Alzheimer's disease (AD) and mild cognitive impairment (MCI). Fourteen AD and 10 MCI subjects were tested using a sentence grammaticality judgement task where grammaticality violations were caused by determiner-noun mismatches, as well as a sentence-picture matching task to assess their ability to access mass and count readings of dual nouns. Considerable heterogeneity was observed within each subject group, and performance across groups was almost identical. It is concluded that a combination of linguistic and attentional and/or learning factors are responsible for the range of impairments; specifically, a subset of subjects exhibit no linguistic nor attentional/learning impairment, another subset exhibit only an attentional and/or learning impairment but no linguistic impairment, and a third subset (comprising more than half of the subjects included in this study) exhibit a linguistic impairment. It is postulated that the latter group have difficulty processing sense extensions in metonymous nouns. It is further claimed that, at least within the limits of the study, language impairments can be of the same severity and nature across AD and MCI subjects.

Aged↗
PubMed2002

Semantic bias, homograph comprehension, and event-related potentials in schizophrenia.

OBJECTIVES: It is controversial whether a semantic processing bias for strong associates is present in schizophrenia, and unknown whether the language abnormalities observed in schizophrenia can be attributed to dysfunctions early or late in cognitive processing. Combined behavioral and event-related potential (ERP) data can indicate the nature and timing of such abnormalities. METHODS: Sensibility judgements of dominant and subordinate homograph sentences were measured in 12 schizophrenia patients and 13 normal controls. ERPs were recorded to the disambiguating sentence-ending word. RESULTS: All subjects showed greatest misinterpretation of subordinate homograph sentences, but schizophrenia patients particularly misinterpreted these sentence types. For control subjects, subordinate homograph sentences that were classified as nonsensical showed greater N400 than those classified as sensible. By contrast, the N400 of patients was large, regardless of the sensibility judgement--patients' brains initially responded to all subordinate sentences as if nonsensical. These data are consonant with a semantic bias. However, the patients' N400 to dominant homograph sentence endings was also larger than that of controls, a finding not consonant with a semantic bias. CONCLUSIONS: The behavioral results indicate a selective comprehension abnormality in schizophrenia dependent on the content of verbal memory. The ERP results suggest a pervasive contextual memory failure. A semantic activation decay model is proposed to explain these results.

Cognition↗
PubMed1994

Assessment of children with developmental apraxia of speech: a procedure.

General considerations for the assessment process are presented. Then, six assessment goals are defined: (1) Determination of prerequisite behaviors for spoken language; (2) Assessment of current speech and language skills; (3) Definition of the nature and severity of the speech disability and the severity of the handicap; (4) Determination of the effects of facilitating approaches and treatment options; (5) Establishment of the child's prognosis; (6) Determination of the criteria for termination of treatment. Procedures, materials, and tests are described in relation to the assessment goals.

Apraxias↗
PubMed1998

[Not Available].

The six-century-long history of printing is not confined merely to the development of technological processes. Its subject is much wider, for printing touches on almost every sphere of human activity-affecting and being affected by political, economic and sociological changes on our civilization. The article exemplifies the point by considering the importance of printing to the history of the Reformation; to the formation of the new German "standard-language", and to the publication of the first printed literature on practice oriented technology and experimental natural sciences. The second part of the article looks into the relationship between the printer and the typesetter's job profiles and into the advances which have transformed the printing process.

Europe↗
PubMed2005

Determinants of dominance: is language laterality explained by physical or linguistic features of speech?

The nature of cerebral asymmetry of the language function is still not fully understood. Two main views are that laterality is best explained (1) by left cortical specialization for the processing of spectrally rich and rapidly changing sounds, and (2) by a predisposition of one hemisphere to develop a module for phonemes. We tested both of these views by investigating magnetic brain responses to the same brief acoustic stimulus, placed in contexts where it was perceived either as a noise burst with no resemblance of speech, or as a native language sound being part of a meaningless pseudoword. In further experiments, the same acoustic element was placed in the context of words. We found reliable left hemispheric dominance only when the sound was placed in word context. These results, obtained in a passive odd-ball paradigm, suggest that neither physical properties nor phoneme status of a sound are sufficient for laterality. In order to elicit left lateralized cortical activation in normal right-handed individuals, a rapidly changing spectrally rich sound with phoneme status needs to be placed in the context of frequently encountered larger language elements, such as words. This demonstrates that language laterality is bound to the processing of sounds as units of frequently occurring meaningful items and can thus be linked to the processes of learning and memory trace formation for such items rather than to their physical or phonological properties.

Adult↗
PubMedDate not supplied

Fuzzy sets in human anatomy.

Artificial intelligence will have a great impact on the rather traditional field of anatomy. Techniques of artificial intelligence can advance anatomical research in a wide range of applications. Fuzzy logic is especially useful in facilitating the use of natural language in the mathematical description of structures or functions. Examples presented demonstrate the broad use of information technology in anatomical applications, including description and classification, knowledge representation, image processing, and three-dimensional anatomical atlases.

Anatomy↗
PubMed2001

The evolution of intelligence: adaptive specializations versus general process.

Darwin argued that between-species differences in intelligence were differences of degree, not of kind. The contemporary ecological approach to animal cognition argues that animals have evolved species-specific and problem-specific processes to solve problems associated with their particular ecological niches: thus different species use different processes, and within a species, different processes are used to tackle problems involving different inputs. This approach contrasts both with Darwin's view and with the general process view, according to which the same central processes of learning and memory are used across an extensive range of problems involving very different inputs. We review evidence relevant to the claim that the learning and memory performance of non-human animals varies according to the nature of the stimuli involved. We first discuss the resource distribution hypothesis, olfactory learning-set formation, and the 'biological constraints' literature, but find no convincing support from these topics for the ecological account of cognition. We then discuss the claim that the performance of birds in spatial tasks of learning and memory is superior in species that depend heavily upon stored food compared to species that either show less dependence upon stored food or do not store food. If it could be shown that storing species enjoy a superiority specifically in spatial (and not non-spatial) tasks, this would argue that spatial tasks are indeed solved using different processes from those used in non-spatial tasks. Our review of this literature does not find a consistent superiority of storing over non-storing birds in spatial tasks, and, in particular, no evidence of enhanced superiority of storing species when the task demands are increased, by, for example, increasing the number of items to be recalled or the duration of the retention period. We discuss also the observation that the hippocampus of storing birds is larger than that of non-storing birds, and find evidence contrary to the view that hippocampal enlargement is associated with enhanced spatial memory; we are, however, unable to suggest a convincing alternative explanation for hippocampal enlargement. The failure to find solid support for the ecological view supports the view that there are no qualitative differences in cognition between animal species in the processes of learning and memory. We also argue that our review supports our contention that speculation about the phylogenetic development and function of behavioural processes does not provide a solid basis for gaining insight into the nature of those processes. We end by confessing to a belief in one major qualitative difference in cognition in animals: we believe that humans alone are capable of acquiring language, and that it is this capacity that divides our intelligence so sharply from non-human intelligence.

Adaptation, Physiological↗
PubMedDate not supplied

Relationship between gestures and words in children with Down's syndrome and typically developing children in the early stages of communicative development.

BACKGROUND: Previous research has emphasized the importance of gesture in early communicative development. These studies have reported that gestures are used frequently during the first two years of life and may play a transitional role in the language acquisition process. Although there are now numerous descriptions of the relationship between gesture and the developing language system in typically-developing (TD) children, relatively little is known about the nature and early development of the gesture-language system in children with developmental disorders involving specific profiles of language delay and/or impairment. PRIMARY OBJECTIVE: The aim of this study is to compare early word and gesture use in children with DS and in typically-developing children to investigate potential differences in the relationship between gestural and verbal communication in early language development. METHODS AND PROCEDURES: Ten children from upper-middle class families participated in the study. The five children with DS (3 boys and 2 girls) had an average chronological age of 47.6 months, an average mental age of 22.4 months, and an average language age of 18 months. Each child with DS was matched to a typically developing child on the basis of gender, language age, and observed expressive vocabulary size. Children were videotaped for 30 minutes as they interacted spontaneously with their mothers. All communicative and intelligible gestures and words produced by the children were transcribed from the videotapes. Data analyses focused on: a) overall production of gestures and words (i.e., gesture and word tokens); b) the size of children's gestural and verbal repertoires (i.e., gesture and word types); and c) production and informational content of gesture-word combinations. MAIN OUTCOMES AND RESULTS: Although children with DS had significantly smaller gestural repertoires than their language age-matched peers, there was no reliable difference between the two groups in the overall use of gesture. In addition, with DS produced two-element combinations (primarily gesture-word combinations) and did so at a rate comparable to that observed among their TD counterparts. However, no two-word combinations were observed among children with DS, and there were also group differences in the information contained in children's gesture-word combinations. CONCLUSIONS: Taken together, these findings suggest that in addition to the well-documented global delays in early communicative development, children with DS may exhibit additional pockets of delay, specifically in making the transition from one- to two-word speech. Results are further discussed in terms of their implications for understanding the organization of the developing gesture-language system and for the assessment of gesture in young children with communicative delays and disorders.

Child, Preschool↗
PubMed2002

[Centenary of the Health Council of the Netherlands. VI. Coordination mechanisms and the authority of the Health Council of the Netherlands].

What do scientific advisory boards such as the Health Council of the Netherlands get their authority from? How does the Council ensure that its advice is incorporated into policy and into the practices at which the advice is directed? A frequently heard answer to this question is: by describing 'the state of knowledge' as optimally as possible. However, case studies on advisory work by the Health Council have shown that this explanation is too simplistic. It is more likely that the explanation lies in the use of 'co-ordination tools'--such as problem definition, the committee process and a specific use of language--that enable the Council to both separate and bridge science and policy. The authority of the Council is based on the hybrid nature of its work.

Advisory Committees↗
PubMed1983

[The search for meaning--the subject and freedom, a psychoanalytic contribution].

Behaviour or symptoms of neurotic nature are characterized as actions provided we succeed in uncovering their "secret motives" by construction or reconstruction. I. e. we may say insofar we succeed in describing the "whither", the "what for" (S. Freud), to which necessarily belongs "from where" (s. Freud, 1916/17, p. 284, 277) we find sense in nonsense. We also say, that sense already was in existence insofar defense mechanisms were operating preventing its overt expression. But we say sense and rationality have been constituted insofar something, which has never been translated into conscienceness, was raised to the level of language. Both processes take place during the psycho-analytic situation. The following preconditions are apparently necessary for their realization: a) the experience of the acknowledgement of a basic drive-wish by the therapist. This event has the character of evidential nature and as to this is in itself preverbal. Nevertheless we need a verbal phrasing of the corresponding interaction and the accompanying emotion in order that both may be included into the executive power of the ego, i.e. the subject. The strict obedience to the rules of a setting which bind both, patient and therapist at the same time. Because of this a firm basis exists which cannot be doubted. It forms the common background object (J. Grotstein) by which and through which both partners of the dialogue may be "at-one" with one another and to which they may also return insofar further developmental events of their interactional process produce alienations and is pushing them to turn to different external objects. Insofar processes as just alluded to take place, the subject is predicated in a play of argumentated reasoning. And if secret motives and hidden reasons concerning the presented modality of the subject's actions are understood, the subject itself realizes, that it has its origin not in its products but in a negation, in a "zero" position which in itself is a equivalent of freedom. In order that interpretative work in the service of the aims just mentioned may become possible, there are some other preconditions to be fulfilled by the therapist: a) the attitude of "evenly hovering attention" (S. Freud) because it is this attitude which makes the therapist receptive for emotional cathexis, originating in the patient's unconscious.(ABSTRACT TRUNCATED AT 400 WORDS)

Freedom↗
PubMedDate not supplied

Twin study of central auditory processing disorder.

We compared auditory, cognitive, and language test results in a pair of dizygotic twins, one of whom showed symptoms of central auditory processing disorder (CAPD). Results highlight the importance of testing binaural function. In particular, electrophysiologic measures of dichotic listening effectively demonstrated the auditory-specific nature of this child's listening problems. The importance of a thorough and comprehensive evaluation of children suspected of CAPD is stressed.

Audiometry, Pure-Tone↗
PubMed1997

Temporolimbic or transcallosal connections: where is the primary lesion in schizophrenia and what is its nature?

A critique of the article by Bogerts on the temporolimbic system theory is presented. Schizophrenia is conceived as arising as a component of the diversity of interhemisphric (callosal) connectivity associated with the evolution of language, a process that occurred through a genetic change (the speciation event) that allowed the hemispheres to develop with a degree of independence. Language and psychosis thus have a common evolutionary origin. The anatomical changes can be considered as a boundary component of the anatomical variation that is characteristic of the species.

Biological Evolution↗