Improving language without words: first evidence from aphasia

The pervasiveness of word-finding difficulties in aphasia has motivated several theories regarding management of the deficit and its effectiveness. Recently, the hypothesis was advanced that instead of simply accompanying speech gestures participate in language production by increasing the semantic activation of words grounded in sensory-motor features, hence facilitating retrieval of the word form. Based on this assumption, several studies have developed rehabilitation therapies in which the use of gestures reinforces word recovery. Until now, however, no studies have investigated the beneficial effects of gesture observation in word retrieval.Here, we report whether a different modality of accessing action-motor representation interacts with language by promoting long lasting recovery of verb retrieval deficits in aphasic patients.Six aphasic participants with a selective deficit in verb retrieval participated in an intensive rehabilitation training that included three daily sessions over two consecutive weeks. Each session corresponded to a different rehabilitation procedure: (1) “action observation”, (2) “action observation and execution”, and (3) “action observation and meaningless movement”. In the four participants with lexical phonologically based disturbances, significant improvement of verb retrieval was found only with “action observation” and “action observation and execution”. No significant differences were present between the two procedures. Moreover, the follow-up testing revealed long-term verb recovery that was still present two months after the two treatments ended.In support of a multimodal representation of action, these findings univocally demonstrate that gestures interact with the speech production system, inducing long-lasting modification at the lexical level in patients with cerebral damage.     

Quantifier processing can be dissociated from numerical processing: Evidence from semantic dementia patients

Quantifiers such as frequency adverbs (e.g., “always”, “never”) and quantity pronouns (e.g., “many”, “none”) convey quantity information. Whether quantifiers are processed as numbers or as general semantics has been a matter of much debate. Some neuropsychological and fMRI studies have found that the processing of quantifiers depends on the numerical magnitude comprehension system, but others have found that quantifier processing is associated with semantic representation. The selective impairment of language in semantic dementia patients provides a way to examine the above controversy. We administered a series of neuropsychological tests (i.e., language processing, numerical processing and semantic distance judgment) to two patients with different levels of severity in semantic dementia (mild vs. severe). The results showed that the two patients had intact numerical knowledge, but impairments in semantic processing. Moreover, the patient with severe/late semantic dementia showed more impairment in quantifier and semantic processing than the patient with mild/early semantic dementia. We concluded that quantifier processing is associated with general semantic processing, not with numerical processing.     

Auditory temporal processing and dyslexia in an orthographically consistent language

We examined two hypotheses relating auditory processing to dyslexia in Greek, an orthographically consistent language. Study I examined the “P-center” or “beat detection” hypothesis (Goswami et al., 2002) in a sample of Grade 6 dyslexics, Grade 6 chronological age (CA) controls, and Grade 4 reading age (RA) controls. Study II examined the “temporal processing,” or “rapid auditory processing” hypothesis (Tallal, 1980) in a sample of Grade 7 dyslexics, CA controls, and in two groups of CA matched children with low frequency discrimination or low tone sequencing performance. Both studies indicate that (a) as a group, dyslexic children did not perform significantly worse on auditory processing measures than the control groups; (b) measures of auditory processing mostly did not account for unique amount of variance in phonological processing, reading, or spelling; and (c) at an individual level of analysis, some of the dyslexic children experienced auditory temporal processing deficits. Implications on the importance of auditory processing in reading in orthographically consistent languages are discussed.     

Prism adaptation differently affects motor-intentional and perceptual-attentional biases in healthy individuals

Prism adaptation (PA) has been shown to affect performance on a variety of spatial tasks in healthy individuals and neglect patients. However, little is still known about the mechanisms through which PA affects spatial cognition. In the present study we tested the effect of PA on the perceptual-attentional “where” and motor-intentional “aiming” spatial systems in healthy individuals. Eighty-four participants performed a line bisection task presented on a computer screen under normal or right-left reversed viewing conditions, which allows for the fractionation of “where” and “aiming” bias components (Schwartz et al., 1997). The task was performed before and after a short period of visuomotor adaptation either to left- or right-shifting prisms, or control goggles fitted with plain glass lenses. Participants demonstrated initial leftward “where” and “aiming” biases, consistent with previous research. Adaptation to left-shifting prisms reduced the leftward motor-intentional “aiming” bias. By contrast, the “aiming” bias was unaffected by adaptation to the right-shifting prisms or control goggles. The leftward “where” bias was also reduced, but this reduction was independent of the direction of the prismatic shift. These results mirror recent findings in neglect patients, who showed a selective amelioration of right motor-intentional “aiming” bias after right prism exposure ( [Fortis et al., 2009] and [Striemer and Danckert, 2010a]). Thus, these findings indicate that prism adaptation primarily affects the motor-intentional “aiming” system in both healthy individuals and neglect patients, and further suggest that improvement in neglect patients after PA may be related to changes in the aiming spatial system.     

Monocular patching may induce ipsilateral “where” spatial bias

Spatial bias is an asymmetry of perception and/or representation of spatial information - “where” bias -, or of spatially directed actions - “aiming” bias. A monocular patch may induce contralateral “where” spatial bias (the Sprague effect [Sprague, J. M. (1966). Interaction of cortex and superior colliculus in mediation of visually guided behavior in cat. Science, 153(3743), 1544-1547]). However, an ipsilateral patch-induced spatial bias may be observed if visual occlusion results in top-down, compensatory re-allocation of spatial perceptual or representational resources toward the region of visual deprivation. Tactile distraction from a monocular patch may also contribute to an ipsilateral bias. To examine these hypotheses, neurologically normal adults bisected horizontal lines at baseline without a patch, while wearing a monocular patch, and while wearing tactile-only and visual-only monocular occlusion. We fractionated “where” and “aiming” spatial bias components using a video apparatus to reverse visual feedback for half of the test trials. The results support monocular patch-induced ipsilateral “where” spatial errors, which are not consistent with the Sprague effect. Further, the present findings suggested that the induced ipsilateral bias may be primarily induced by visual deprivation, consistent with compensatory “where” resource re-allocation.     

Emergence of hierarchical structure mirroring linguistic composition in a recurrent neural network

We show that a Multiple Timescale Recurrent Neural Network (MTRNN) can acquire the capabilities to recognize, generate, and correct sentences by self-organizing in a way that mirrors the hierarchical structure of sentences: characters grouped into words, and words into sentences. The model can control which sentence to generate depending on its initial states (generation phase) and the initial states can be calculated from the target sentence (recognition phase). In an experiment, we trained our model over a set of unannotated sentences from an artificial language, represented as sequences of characters. Once trained, the model could recognize and generate grammatical sentences, even if they were not learned. Moreover, we found that our model could correct a few substitution errors in a sentence, and the correction performance was improved by adding the errors to the training sentences in each training iteration with a certain probability. An analysis of the neural activations in our model revealed that the MTRNN had self-organized, reflecting the hierarchical linguistic structure by taking advantage of the differences in timescale among its neurons: in particular, neurons that change the fastest represented “characters”, those that change more slowly, “words”, and those that change the slowest, “sentences”.     

Characteristics of number transcoding errors of Chinese- versus English-speaking Alzheimer's disease patients

ABSTRACT

Number processing disorder is an acquired deficit in mathematical skills commonly observed in Alzheimer’s disease (AD), usually as a consequence of neurological dysfunction. Common impairments include syntactic errors (800012 instead of 8012) and intrusion errors (8 thousand and 12 instead of eight thousand and twelve) in number transcoding tasks. This study aimed to understand the characterization of AD-related number processing disorder within an alphabetic language (English) and ideographical language (Chinese), and to investigate the differences between alphabetic and ideographic language processing. Chinese-speaking AD patients were hypothesized to make significantly more intrusion errors than English-speaking ones, due to the ideographical nature of both Chinese characters and Arabic numbers. A simplified number transcoding test derived from EC301 battery was administered to AD patients. Chinese-speaking AD patients made significantly more intrusion errors (p = 0.001) than English speakers. This demonstrates that number processing in an alphabetic language such as English does not function in the same manner as in Chinese. The impaired inhibition capability likely contributes to such observations due to its competitive lexical representation in brain for Chinese speakers.     

Le jeu comme « leurre » et le démenti

In the cure, according to our hypothesis, the games played by children obey different unconscious logics, which reveals the importance of envisioning the reception of different types of play in the cure. We propose a Freudian-inflected “structural classification of play,” drawing upon similar attempts made by Piaget for developmental psychology, and Caillois for sociology. We will consider that certain play follows a logic of negation (Verneinung) – play that we call “trompe-l’oeil” games; or a logic of disavowal (Verleugnung) – “decoy” games; or a logic of foreclusion (Verwerfung) – “suppléance” games. This article develops the type of play associated with the mechanism of disavowal: the game as decoy. We draw upon and analyse an example from the literature – that of Arpad, the “little chanticleer” received by S. Ferenczi in 1913. The examination of this case allows us to clarify the reasons for which such games can be an obstacle to the cure, as well as to the establishment and development of the transference. We will be led to cast doubt upon the possibility of considering such play to be “therapeutic” in the sense of winnicottian playing. Following the hypothesis that such play does not favour subjective change, we will propose a comparison with “trompe-l’oeil” and “suppléance” games.     

Syntax without language: Neurobiological evidence for cross-domain syntactic computations

Not all conceivable grammars are realized within human languages. Rules based on rigid distances, in which a certain word must occur at a fixed distance from another word, are never found in grammars of human languages. Distances between words are specified in terms of relative, non-rigid positions. The left inferior frontal gyrus (IFG) (Broca's area) has been found to be involved in the computation of non-rigid but not of rigid syntax in the language domain. A fundamental question is therefore whether the neural activity underlying this non-rigid architecture is language-specific, given that analogous structural properties can be found in other cognitive domains. Using event-related functional magnetic resonance imaging (fMRI) in sixteen healthy native speakers of Italian, we measured brain activity for the acquisition of rigid and non-rigid syntax in the visuo-spatial domain. The data of the present experiment were formally compared with those of a previous experiment, in which there was a symmetrical distinction between rigid and non-rigid syntax in the language domain. Both in the visuo-spatial and in the language domain, the acquisition of non-rigid syntax, but not the acquisition of rigid syntax, activated Brodmann Area 44 of the left IFG. This domain-independent effect was specifically modulated by performance improvement. Thus, in the human brain, one single “grammar without words” serves different higher cognitive functions.     

Dimensions of adolescent subjective social status within the school community: Description and correlates

School pupils strive to meet both school-defined and social goals, and the structure of adolescent self-concept is multidimensional, including both academic and non-academic self-perceptions. However, subjective social status within the school community has been represented as a single dimension. Scottish 15-year olds participating in a school-based survey (N = 3194) rated their own status, compared to their school year-group, via images of seven 10-rung ladders. These generated a very high response rate, and factor analysis distinguished three dimensions: (1) ladders representing “popular”, “powerful”, “respected”, “attractive or stylish” and “trouble-maker”; (2) “doing well at school” and “[not] a trouble-maker”; and (3) “sporty”. Unique relationships with variables representing more objective and/or self-report behavioural measures suggest these dimensions are markers of “peer”, “scholastic” and “sports” status. These analyses suggest multiple dimensions of adolescent social hierarchy can be very simply measured and contribute towards the development of more robust instruments within this area.     

Entre affect et apprentissage, la question de la perte. Inhibition psychique et inhibition cognitive

In front of the extent of the parental or school requests relating to “the school failure”, this text is of the interest to articulate the concept of inhibition in psychoanalysis and that of inhibition in cognitive psychology. How does one learn? Which are the unconscious and cognitive stakes of the “bankruptcy” of the training? Of which logic of “renouncement” answers inhibition useful for training and psychic inhibition being able to be transformed into a school symptom? The examination of these logics will carry out to a proposal for an assumption of responsibility clinical associating psychotherapy and an educational work of handing-over moving of the intellectual processes.     

Letter and letter-string processing in developmental dyslexia

This study evaluated letter recognition processing in Italian developmental dyslexics and its potential contribution to word reading. Letter/bigram recognition (naming and matching) and reading of words and non-words were examined. A group of developmental dyslexics and a chronologically age-matched group of skilled readers were examined. Dyslexics were significantly slower than skilled readers in all tasks. The rate and amount model (RAM, Faust et al., 1999) was used to detect global and specific factors in the performance differences controlling for the presence of over-additivity effects. Two global factors emerged. One (“letter-string” factor) accounted for the performance in all (and only) word and non-word reading conditions, indicating a large impairment in dyslexics (more than 100% reaction time - RT increase as compared to skilled readers). All the letter/bigram tasks clustered on a separate factor (“letter” factor) indicating a mild impairment (ca. 20% RT increase as compared to skilled readers). After controlling for global factor influences by the use of the z-score transformation, specific effects were detected for the “letter-string” (but not the “letter”) factor. Stimulus length exerted a specific effect on dyslexics' performance, with dyslexics being more affected by longer stimuli; furthermore, dyslexics showed a stronger impairment for reading words than non-words. Individual differences in the “letter” and “letter-string” factors were uncorrelated, pointing to the independence of the impairments. The putative mechanisms underlying the two global factors and their possible relationship to developmental dyslexia are discussed.     

Depression in Down syndrome: a review of the literature

Background

Depression has been frequently reported in individuals with Down Syndrome (DS). The aim of this article is to provide a comprehensive, critical review of the clinically relevant literature concerning depression in DS, with a focus on epidemiology, potential risk factors, diagnosis, course characteristics and treatment.

Methods

We searched the PUBMED database (January 2011) using the keywords (“Depressive Disorder [MESH]” OR “Depression [MESH]” OR “depress* [All Fields]”) AND (“Down Syndrome [MESH]” OR “Down syndrome [All Fields]” OR “Down's syndrome [All Fields]”). Review articles not adding new information, single case reports and papers focusing on subjects other than depression in DS were excluded.

Results

The PUBMED search resulted in 390 articles, of which 30 articles were finally included. Recent information does not support earlier suggestions of an increased prevalence of depression in DS compared to other causes of Intellectual Disability (ID). However, individuals with DS show many vulnerabilities and are exposed to high levels of stressors that could confer an increased risk for the development of depression. Apart from general risk factors, several potential risk factors are more specific for DS, including smaller hippocampal volumes, certain changes in neurotransmitter systems, deficits in language and working memory, attachment behaviours and frequently occurring somatic disorders. Protective factors might play a role in reducing the vulnerability to depression. The diagnosis of depression in DS is mainly based upon observable characteristics, and therefore, the use of modified diagnostic criteria is advised.Although several common treatments, including antidepressants, electroconvulsive therapy and psychotherapy seem effective, there is evidence of undertreatment of depression in DS.

Conclusions

There are important limitations to our current clinical knowledge of depression in DS. Future studies should include systematic evaluations of pharmacotherapeutic and psychotherapeutic interventions.     

Syntax, concepts, and logic in the temporal dynamics of language comprehension: Evidence from event-related potentials

Logic has been intertwined with the study of language and meaning since antiquity, and such connections persist in present day research in linguistic theory (formal semantics) and cognitive psychology (e.g., studies of human reasoning). However, few studies in cognitive neuroscience have addressed logical dimensions of sentence-level language processing, and none have directly compared these aspects of processing with syntax and lexical/conceptual-semantics. We used ERPs to examine a violation paradigm involving “Negative Polarity Items” or NPIs (e.g., ever/any), which are sensitive to logical/truth-conditional properties of the environments in which they occur (e.g., presence/absence of negation in: John hasn’t ever been to Paris, versus: John has *ever been to Paris). Previous studies examining similar types of contrasts found a mix of effects on familiar ERP components (e.g., LAN, N400, P600). We argue that their experimental designs and/or analyses were incapable of separating which effects are connected to NPI-licensing violations proper. Our design enabled statistical analyses teasing apart genuine violation effects from independent effects tied solely to lexical/contextual factors. Here unlicensed NPIs elicited a late P600 followed in onset by a late left anterior negativity (or “L-LAN”), an ERP profile which has also appeared elsewhere in studies targeting logical semantics. Crucially, qualitatively distinct ERP-profiles emerged for syntactic and conceptual semantic violations which we also tested here. We discuss how these findings may be linked to previous findings in the ERP literature. Apart from methodological recommendations, we suggest that the study of logical semantics may aid advancing our understanding of the underlying neurocognitive etiology of ERP components.     

Critique de l’utilisation de l’enseignement de Jacques Lacan dans l’abord psychanalytique des troubles psychotiques ou d’une question postliminaire à tout traitement possible de la psychose

Lacan has left a teaching, mainly in his “seminars”, which is often synthesized, simplified and reduced to a simple explanatory theory, principally regarding psychotic process. Such a simplifying view can become a discriminatory, iatrogenic conception of the psychotic person and of the psychotherapeutic (or psychoanalytical) treatment. In the first part of this paper, the author tries to show that Lacan’s teaching was principally a transmission of the psychoanalysis itself, in different ways, as half-sayings, ambiguity, poetry and style, topology, mathems… Lacan passed himself on as a possibility of analytical opening, like in a cure. He does not generate a rational discourse, but he proposed several different theories as simple “vectors”. In the second part, the author puts some concepts as “Name of Father foreclosure”, “borromean knot” and “object a” into a political (within the psychoanalytical community) and historical context. If those items of Lacan’s teaching are diverted from their primal function of “vectors” and are considered as explanatory theories, then they lose their pertinence and can lead to a stigmatizing conception and to possibly iatrogenic attitudes in the treatment. That will be examined further.     

Redefining phenotypes in eating disorders based on personality: a latent profile analysis

To conduct a latent profile analysis (LPA) in eating disorder (ED) patients using temperament and character (TCI-R) measures as indicators. 1312 ED patients including those with anorexia nervosa (AN), bulimia nervosa (BN) and EDNOS were assessed. The final LPA solution was validated using demographics, clinical variables, ED symptomatology (EDI-2) and impulsive behaviors. The best-fitting model consisted of a six-profile solution using the seven subscales of the TCI-R. These profiles were labeled: “self-focused”, “inhibited”, “average”, “impulsive”, “adaptive” and “maladaptive”. Validation analyses indicated that the “inhibited” and “maladaptive” profiles generally presented with the highest values for ED symptomatology and impulsive behaviors. Whereas high levels of Harm Avoidance and low levels of Novelty Seeking and Persistence characterized the “inhibited” profile, the “maladaptive” profile presented with low levels of Reward Dependence, Self-Directedness and Cooperativeness. The most favorable results on the other hand were exhibited by the “adaptive” profile, characterized by high scores on Reward Dependence, Self-Directedness, Cooperativeness and low levels on Novelty Seeking. Finally, when our six-profile solution was compared with the DSM-IV ED diagnoses, significant differences among profiles and ED diagnoses were observed. Our study shows that ED patients can be meaningfully grouped according to temperament and character.     

¿Existe la enfermedad de Alzheimer en todos los primates? Patología Alzheimer en primates no humanos y sus implicaciones fisiopatológicas (II)

Introduction

In the ageing process there are some species of non-human primates which can show some of the defining characteristics of the Alzheimer's disease (AD) of man, both in neuropathological changes and cognitive-behavioural symptoms. The study of these species is of prime importance to understand AD and develop therapies to combat this neurodegenerative disease.

Development

In this second part of the study, these AD features are discussed in the most important non-experimental AD models (Mouse Lemur —Microcebus murinus, Caribbean vervet —Chlorocebus aethiops, and the Rhesus and stump-tailed macaque —Macaca mulatta and M. arctoides) and experimental models (lesional, neurotoxic, pharmacological, immunological, etc.) non-human primates. In all these models cerebral amyloid neuropathology can occur in senility, although with different levels of incidence (100% in vervets; < 30% in macaques). The differences between normal and pathological (Alzheimer's) senility in these species are difficult to establish due to the lack of cognitive-behavioural studies in the many groups analysed, as well as the controversy in the results of these studies when they were carried out. However, in some macaques, a correlation between a high degree of functional brain impairment and a large number of neuropathological changes (“possible AD”) has been found.

Conclusions

In some non-human primates, such as the macaque, the existence of a possible continuum between “normal” ageing process, “normal” ageing with no deep neuropathological and cognitive-behavioural changes, and “pathological ageing” (or “Alzheimer type ageing”), may be considered. In other cases, such as the Caribbean vervet, neuropathological changes are constant and quite marked, but its impact on cognition and behaviour does not seem to be very important. This does assume the possible existence in the human senile physiological regression of a stable phase without dementia even if neuropathological changes appeared.