Nicolas Stefaniak

Exploration of serial structure procedural learning in children with language impairment.

Recent studies on specific language impairment (SLI) have suggested that language deficits are directly associated with poor procedural learning abilities. Findings from our previous work are contrary to this hypothesis; we found that children with SLI were able to learn eight-element-long sequences as fast and as accurately as children with normal language (NL) on a serial reaction time (SRT) task. A probabilistic rather than a deterministic SRT paradigm was used in the current study to explore procedural learning in children with SLI to mimic real conditions of language learning. Fifteen children with or without SLI were compared on an SRT task including a probabilistic eight-element-long sequence. Results show that children with SLI were able to learn this sequence as fast and as accurately as children with NL, and that similar sequence-specific learning was observed in both groups. These results are novel and suggest that children with SLI do not display global procedural system deficits.

The Basic Empathy Scale in adults (BES-A): factor structure of a revised form.

Initially thought of as a unitary ability, empathy has been more recently considered to consist of 2 components (i.e., an affective and a cognitive component). The Basic Empathy Scale (BES) is a tool that has been used to assess empathy in young people and adolescents on the basis of this dual-component conception (Jolliffe & Farrington, 2006). Recent studies of empathy have led to it being defined as underpinned by 3 components, namely, emotional contagion, emotional disconnection, and cognitive empathy. The aims of this study were (a) to validate the BES in Adults and (b) to compare the different conceptions of empathy. Three hundred seventy French adults took part in the study, and 160 of them filled out complementary scales measuring empathy, alexithymia, and emotional consciousness. The confirmatory factor analyses showed that the 3-factor model was the model that was best able to account for the data. Complementary tools confirmed the relationships previously observed between empathy as assessed with the BES and other scales assessing emotional processes. The results of this study make it clear that empathy can be seen as process-dependent. This conception of empathy, which is based on 3 factors, is consistent with the current, more integrated view of empathy. The implications of this conception and the opportunity to use the 2 or 3 factors of the BES in adults are presented in the discussion.

Procedural Learning in Specific Language Impairment: Effects of Sequence Complexity

According to the procedural deficit hypothesis (PDH), abnormal development in the procedural memory system could account for the language deficits observed in specific language impairment (SLI). Recent studies have supported this hypothesis by using a serial reaction time (SRT) task, during which a slower learning rate is observed in children with SLI compared to controls. Recently, we obtained contrasting results, demonstrating that children with SLI were able to learn a sequence as quickly and as accurately as controls. These discrepancies could be related to differences in the statistical structure of the SRT sequence between these studies. The aim of this study was to further assess, in a group of 21 children with SLI, the PDH with second-order conditional sequences, which are more difficult to learn than those used in previous studies. Our results show that children with SLI had impaired procedural memory, as evidenced by both longer reaction times and no sign of sequence-specific learning in comparison with typically developing controls. These results are consistent with the PDH proposed by Ullman and Pierpont (2005) and suggest that procedural sequence-learning in SLI children depends on the complexity of the to-be-learned sequence.

Executive functions in adult offspring of alcohol-dependent probands: toward a cognitive endophenotype?

BACKGROUND Executive function (EF) impairment in alcohol dependence (AD) has been related to the toxic effects of alcohol on frontal lobes. However, this impairment could be partially present before the onset of the disease and might constitute a vulnerability factor. Although a considerable body of research has investigated executive functioning among AD patients, much less attention has been directed toward high-risk individuals. Most studies were carried out among children or adolescents, and very few were conducted in adults. The aim of this study was to examine EF in a group of adult offspring of AD individuals. METHODS One hundred and fifty-five nonalcoholic adults with (family history positive [FHP]) or without (family history negative [FHN]) family history of AD were included in the study. All participants were screened for past and current psychiatric diagnoses, and alcohol, tobacco, and other substance use. They were compared on self-rated impulsiveness using the Barratt Impulsiveness Scale-11 (BIS-11) and EF using a neuropsychological test battery. RESULTS Group comparison revealed that FHP participants had significantly higher BIS-11 scores than the FHN participants, while neuropsychological examination revealed lower EF scores for FHP participants. Hierarchical regression analysis revealed that the number of AD family members was a predictor of EF results, whereas impulsiveness was not. CONCLUSIONS Nonalcoholic adult offspring of AD individuals showed increased impulsiveness and decreased EF, suggesting weakness of 2 distinct neurobehavioral decision systems. Findings support evidence that EF weaknesses may qualify as a suitable endophenotype candidate for AD.

What is the impact of the explicit knowledge of sequence regularities on both deterministic and probabilistic serial reaction time task performance

The aim of this study was to explore the role of prior explicit sequence knowledge by comparing its influence on serial reaction time (SRT) performance with either a deterministic or a probabilistic sequence. The results confirm that, with a deterministic sequence, preliminary explicit learning improves SRT performance. On the other hand, with a probabilistic sequence, the results show no advantage for SRT performance in explicitlearning conditions. In addition, by using the process dissociation procedure (Jacoby, 1991), we show that performance on a subsequent generation task was more sustained by controlled processes for participants in the explicit-learning conditions than for those in the incidental condition. On the whole, these results, showing that the influence of explicit knowledge can be suppressed in certain specific conditions, are consistent with the intervention of both implicit and explicit mechanisms in SRT tasks, and the results also show that their relative influence can be modulated by the particular demands of the task.

Brain-derived neurotrophic factor (BDNF) Val66Met polymorphism and its implication in executive functions in adult offspring of alcohol-dependent probands

Impairment of executive functions (EFs) mediated by the prefrontal lobe is regarded as a cognitive endophenotype of alcohol dependence, being observed both in probands and in healthy offspring. Given its impact on the anatomy of the prefrontal cortex, the brain-derived neurotrophic factor (BDNF) Val66Met polymorphism may well be involved in this specific endophenotype. Forty-six healthy adult children of alcoholics (HACA) and 82 healthy controls (HC) took part in the study. All the participants were assessed with the Diagnostic Interview for Genetic Studies, and their family histories of alcohol and substance use were assessed with the Family Informant Schedule and Criteria. The Trail Making Test, Arithmetic Switching Task, Stroop Color-Word Test and Wisconsin Card Sorting Test were administered to assess EFs. An overall executive factor score was calculated using factorial analyses. Genotyping of the BDNF Val66Met polymorphism was performed using the TaqMan® allelic discrimination assay. HACA had significantly lower EFs performance than HC. Genetic analysis showed that BDNF genotype distributions were in Hardy-Weinberg equilibrium in the HACA and HC. Genotype and allele distributions did not differ significantly between the two groups. Participants with the Met allele performed significantly more poorly than participants with the Val allele, and a group by allele interaction was observed, the BDNF Met allele being associated with a poorer executive factor score in the HACA group. These results suggest that the BDNF Val66Met polymorphism may contribute to alcohol dependence vulnerability via lower EFs performance.

Theory of mind and hypomanic traits in general population

Theory of Mind (ToM) is the ability to assign a set of mental states to yourself and others. In bipolar disorders, alteration of social relationship can be explained by the impairment of the functioning of ToM. Deficit in ToM could be a trait marker of bipolar disorder and people in the general population with high hypomanic personality scores would be more likely to develop bipolar disorders. This study examined 298 participants. Measures of hypomanic personality were evaluated using the Hypomanic Personality Scale. ToM was explored using the Yoni task. Participants also completed the BDI-II. Forward multiple regressions were performed to examine the effect of components of the HPS on the total score in the ToM task. In the womens group, no subscales of the HPS were included in the model. Conversely, the analyses performed on men revealed that the mood vitality and excitement subscale was a significant predictor of ToM abilities. Our study is the first to show the impact of certain dimensions of hypomanic personality on performance in ToM in a male sample. This result supports the idea that deficits in ToM can be a trait marker of bipolar disorder in a healthy male population.

Impaired conscious memory in non-clinical schizotypy

Introduction. Impaired controlled and preserved/enhanced automatic memory processes have been reported in schizotypy. This memory pattern has been considered as a marker of vulnerability to schizophrenia. Our aim was to further explore this memory pattern in non-clinical schizotypy in order to determine which specific dimensions of schizotypy (i.e., positive, negative or disorganised), and more specifically which components of the dimensions, are most closely related to memory dysfunctions. Methods. Fifty-seven undergraduate students performed a category-production task. This was adapted for use with the process dissociation procedure in order to dissociate between automatic and controlled memory processes. The level of schizotypy was assessed using the Schizotypal Personality Questionnaire. Results. Regression analyses confirmed that controlled memory processes decreased as schizotypy increased. The positive factors (more specifically, the ideas of reference subscale) and disorganised factors (more specifically, the odd or eccentric behaviour subscale) were negatively correlated with the controlled memory processes. Conclusions. Our study supports the idea that impaired controlled processes are an early cognitive marker of vulnerability to schizophrenia and confirm that the disorganised factor contributes the most to vulnerability to memory dysfunction. It also emphasises the importance of dissociating between each of the features characterising schizotypy rather than considering it as a whole.

L’apprentissage de nouvelles informations sémantiques par les patients amnésiques : une revue de la littérature

L’etude de la capacite qu’ont les patients amnesiques d’apprendre de nouvelles informations semantiques connait un regain d’interet depuis une dizaine d’annees, notamment suite aux travaux de Vargha-Khadem et collaborateurs (1997) et a l’impact de ceux-ci tant sur notre comprehension des relations entre memoire semantique et memoire episodique que sur la maniere d’envisager, au plan clinique, la prise en charge de ces patients. Cette revue de litterature a pour but de presenter l’etat de nos connaissances sur ce sujet, en cherchant a repondre a differentes questions : Quelles sont les relations entre memoire episodique et memoire semantique ? En quoi l’etude de patients amnesiques peut-elle apporter des elements de reponses dans ce debat ? Les patients amnesiques peuvent-ils veritablement apprendre de nouvelles informations semantiques ? Et si oui, quelle est l’etendue et la nature des connaissances qu’ils peuvent acquerir ?

Role of implicit learning abilities in metaphor understanding

Although the use of metaphors is a central component of language, the processes that sustain their comprehension have yet to be specified. Work in the fields of both metaphors and implicit learning suggests that implicit learning abilities facilitate the comprehension of metaphors. However, to date, no study has directly explored the relationships between the understanding of metaphors and so-called implicit learning tasks. We used a meaning decision task comparing literal, metaphorical and meaningless expressions to assess metaphor understanding and a probabilistic serial reaction time task for assessing implicit learning. Our results show that implicit learning positively predicts the time gap between responses to literal and metaphorical expressions and negatively predicts the difference between metaphorical and meaningless expressions. Thus, when confronted with novel metaphors, participants with higher implicit learning abilities are better able to identify that the expressions have some meaning. These results are interpreted in the context of metaphor understanding and psycholinguistic theories.