Positive and negative emotion induction through avatars and its impact on reasoning performance: cardiovascular and pupillary correlates

International audienceMany studies have shown the impact of emotion on cognition (Damasio, 1994), however these influences remain ambiguous. The contradictions may be explained by a lack of experimental control (emotional induction, objective clues on emotional states...) but also by the existence of complex cross-influences between the dorsolateral prefrontal cortex, a major substratum of executive functions (EFs) and the ventromedial prefrontal cortex, an area strongly connected to the limbic system. This work aimed at gaining a more precise view of the links between emotion and EFs, utilizing an experimental protocol that used avatars for a well-controlled emotional induction, measurements of the autonomic nervous system activity as evidence of the emotional state (cardiovascular and pupillary responses) and a neuropsychological test battery (dynamic reasoning and deductive reasoning tasks) for the detection of EFs variations in response to emotion. The experimental data showed that positive emotion (joy) led to a performance decrease during both tasks, together with physiological variations. These counterintuitive results showed that positive mood can impair executive functioning in our tasks. In addition, our results highlighted the lack of learning effects on deductive performance

ERP and behavioral evidence for interaction/cascade between central (linguistic) and peripheral (motor) processes during word handwriting

International audienceModels of handwritten language production make a distinction between central (access to semantic, orthographic and phonological information) and peripheral (allographic and gesture planning) processes (see van Galen, 1991; Rapp, 2002). Though, this is still a matter of debate whether these central and peripheral modules are processed in a cascaded or in a serial way (Delattre, Barry & Bonin, 2006; Damian & Stadthagen-Gonzalez, 2009). In the same view, another question still debated is ”do central and peripheral processes ‘interact’ in handwritten word production compared to oral naming”

ERP Characterization of Sustained Attention Effects in Visual Lexical Categorization

As our understanding of the basic processes underlying reading is growing, the key role played by attention in this process becomes evident. Two research topics are of particular interest in this domain: (1) it is still undetermined whether sustained attention affects lexical decision tasks; (2) the influence of attention on early visual processing (i.e., before orthographic or lexico-semantic processing stages) remains largely under-specified. Here we investigated early perceptual modulations by sustained attention using an ERP paradigm adapted from Thierry et al. [1]. Participants had to decide whether visual stimuli presented in pairs pertained to a pre-specified category (lexical categorization focus on word or pseudoword pairs). Depending on the lexical category of the first item of a pair, participants either needed to fully process the second item (hold condition) or could release their attention and make a decision without full processing of the second item (release condition). The P1 peak was unaffected by sustained attention. The N1 was delayed and reduced after the second item of a pair when participants released their attention. Release of sustained attention also reduced a P3 wave elicited by the first item of a pair and abolished the P3 wave elicited by the second. Our results are consistent with differential effects of sustained attention on early processing stages and working memory. Sustained attention modulated early processing stages during a lexical decision task without inhibiting the process of stimulus integration. On the contrary, working memory involvement/updating was highly dependent upon the allocation of sustained attention. Moreover, the influence of sustained attention on both early and late cognitive processes was independent of lexical categorization focus

Redefiniendo la dislexia: explicando la variabilidad

The scientific effervescence that reigns around developmental dyslexia is explained by the difficult challenge that consists of ascribing this handicap to a single cause whilst multiple profiles of dyslexic patients can be observed. In this chapter, we start by presenting the main neuro-cognitive hypotheses that aim to explain dyslexia. We then review the multidimensional nature of dyslexia, and discuss the necessity of using a common diagnostic criteria to improve our understanding of its true nature. We then conclude by presenting promising work connecting cerebral endophenotypes and behavioral phenotypes highlighting the need for a multi-factorial rather than mono-theoretical account of developmental dyslexia.La efervescencia científica que reina en torno a la dislexia evolutiva se explica por el difícil desafío que implica atribuir esta dificultad a una causa simple al tiempo que se observan pacientes disléxicos con múltiples perfiles. En este capítulo, empezamos presentando la hipótesis neurocognitiva principal que persigue explicar la dislexia. Revisaremos la naturaleza multidimensional de la dislexia y discutiremos la necesidad de utilizar un criterio diagnóstico común para mejorar nuestra comprensión de su verdadera naturaleza. Concluiremos con la presentación de un trabajo prometedor que conecta endofenotipos cerebrales y fenotipos conductuales, resaltando la necesidad de un enfoque multifactorial más que monoteórico de la dislexia evolutiva

Second language performances in elderly bilinguals and individuals with dementia: The role of L2 immersion

With the population aging and an increase in the number of senior immigrant citizens in modern societies, public health systems will be increasingly burdened with the need to deal with the care and treatment of bi- or multilingual individuals with cognitive decline and dementia. This raises complex questions such as which language is better preserved in these elderly individuals, particularly for those facing dementias. The main aim of the present investigation was to study in two groups of immigrant populations whether the first language (L1) or the second language (L2) are better preserved. For this purpose, we assessed by means of cognitive and neurolinguistics testing 20 late-bilingual individuals with neurodegenerative dementia of the Alzheimer and mixed type, and compared their results to a matched control group consisting of 19 subjects. Our results suggest that L1 is not better preserved in individuals with dementia. We report a parallel decline of second language across groups, regardless of the presence of dementia, as well as a significant correlation between language immersion and L2 relative performances (r = 0.379, p = 0.03). Moreover our data suggest that individual with dementia may have a relative sparing of syntactic L2 comprehension. These results suggest that these elderly individuals who have lived in a host country for many years, such as the subjects here investigated, may preserve similarly their L2 as much as their L1, irrespectively of the presence or absence of neurodegenerative disease, and even preserve some features of L2 processes in dementia. These results emphasize the role of immersion in language preservation

Induced emotions and impact on reasoning and decision-making

Induced emotions and impact on reasoning and decision-making : contribution of virtual reality and autonomous nervous system measurement

Emotion induction through virtual avatars and its impact on reasoning: evidence from autonomous nervous system measurements and cognitive assessment

Many studies have shown the impact of emotion on cognition (Damasio 1995; Phelps 2004), however these influences remain ambiguous. The contradictions may be explained by a lack of experimental control but also by the existence of complex cross-influences between the dorsolateral prefrontal cortex, a major substratum of the executive functions (EFs) and the ventromedial prefrontal cortex, an area strongly connected to the limbic system (Simpson 2001a). This work aims at gaining a more precise view of the links between emotion and EFs thanks to an experimental protocol that uses Virtual Reality (avatars) for a controlled emotional conditioning, measurements of the autonomous nervous system (ANS) as evidence of the emotional variations and a neuropsychological test battery for the detection of EFs variations, especially reasoning. The battery’s major tasks consist in deductive reasoning and reasoning in dynamic situations. The experimental data show that positive conditioning leads to a performance decrease (in agreement with Phillips et al. (2002a)), together with physiological variations (cardiac and pupillary activity). Moreover negative conditioning leads to ineffective actions: more actions (Dynamic task), more quickly (Deductive task) with no performance variation. These results may have applications in neuropsychology, for the assessment and the rehabilitation of patients (Mateer et al. 2005) and in neuroergonomics in the field of complex working situations where emotions may cause accidents (e.g. potential source of air crashes, Dehais et al. 2003)