Influences de l'environnement linguistique prénatal sur l'émergence des réseaux langagiers à la naissance

Essai doctoral présenté à la Faculté des arts et sciences en vue de l’obtention du grade de Doctorat en psychologie, option neuropsychologie clinique (D. Psy.)Au cours du développement, les réseaux cérébraux s’organisent pour traiter plus efficacement et mieux percevoir les stimuli les plus pertinents dans l’environnement. Déjà lors des premières heures suivant la naissance, les nouveau-nés montrent un traitement cérébral spécifique pour leur langue maternelle comparativement à des langues étrangères, ce qui se manifeste par une implication plus importante des réseaux fonctionnels de l’hémisphère gauche. Notre compréhension des origines de cette organisation fonctionnelle demeure toutefois limitée, notamment en lien avec l’expérience linguistique durant la période prénatale. Pour ce faire, nous avons étudié l’impact d’une exposition prénatale contrôlée à une langue étrangère sur le traitement cérébral et la spécialisation hémisphérique du langage à la naissance. Nous avons utilisé la spectroscopie près du spectre de l’infrarouge pour estimer la réponse cérébrale de 53 nouveau-nés à leur langue maternelle (français) ainsi qu’à deux langues étrangères (allemand et hébreu). Deux groupes avaient préalablement été familiarisés à l’une de ces langues étrangères durant leur dernier mois de gestation, alors qu’un groupe contrôle n’avait eu aucune exposition prénatale à ces stimuli. Nos résultats ont révélé une spécialisation hémisphérique en région temporo-pariétale gauche qui sous-tend le traitement de la langue maternelle à la naissance, et ce, indépendamment de l’expérience prénatale. Par ailleurs, les patrons de réponse cérébrale aux langues étrangères se distinguaient en fonction la manipulation expérimentale de l’expérience linguistique prénatale. En effet, les nouveau-nés familiarisés à l’allemand in utero manifestaient notamment une activation plus grande et également latéralisée dans l’hémisphère gauche en réponse à l’allemand, ce qui n’était pas observé ni dans le groupe familiarisé à l’hébreu ni dans le groupe contrôle. Ceci suggère que l’organisation cérébrale à la naissance montrerait des traces d’apprentissage prénatal. Toutefois, la divergence des réponses en fonction de la langue exposée in utero sous-entend que cet apprentissage prénatal serait modulé par les propriétés phonologiques des langues. En somme, cet essai met en lumière l’implication tant de la familiarité, découlant de l’environnement linguistique in utero, que de caractéristiques phonologiques des langues dans le développement des réseaux langagiers durant la période périnatale.Throughout development, our brain networks adapt to environmentally relevant stimuli to enable a more efficient processing and to refine our perceptual abilities. From the first hours after birth, the newborn brain already displays a specialized processing of his/her native language in comparison to unfamiliar languages, revealed by a larger involvement of left hemispheric functional networks. However, our understanding of the origin of this functional brain organization remains limited, especially in regard to the influence of the linguistic experience during the prenatal stage. The current doctoral essay aims to better understand how the prenatal linguistic environment modulates the development of precursor language networks at birth. To do so, we investigated the impact of a controlled prenatal exposure to an unfamiliar language on the newborn brain processing and hemispheric specialization. We used functional near-infrared spectroscopy to estimate the brain responses of 53 newborns to their native language (French) and two unfamiliar languages (German and Hebrew). During their last month of gestation, two groups were repeatedly exposed to either one of the unfamiliar languages, while a control group received no prenatal exposure to those stimuli. Our results revealed that all newborns displayed a left hemispheric advantage in the temporo-parietal region for their native language, regardless of their prenatal exposure. Moreover, the experimental manipulation of newborns’ prenatal experience triggered a differentiated response pattern when processing non-native languages. Indeed, German-exposed newborns exhibited a left asymmetry and an increased activation in response to the prenatally familiarized German, which was not observed in either the Hebrew-exposed or control newborns. This suggests that the cerebral organization at birth displays evidence of prenatal experience-dependent learning. However, the different cerebral patterns in regard of which language was exposed in utero indicate that phonological properties of the languages may modulate prenatal learning. In sum, this essay highlights that both familiarity, originating from the prenatal linguistic environment, and phonology shape brain language networks during early perinatal development

Assessment of Barriers to Improve Diabetes Management in Older Adults: A randomized controlled study

OBJECTIVE To evaluate whether assessment of barriers to self-care and strategies to cope with these barriers in older adults with diabetes is superior to usual care with attention control. The American Diabetes Association guidelines recommend the assessment of age-specific barriers. However, the effect of such strategy on outcomes is unknown. RESEARCH DESIGN AND METHODS We randomized 100 subjects aged ≥69 years with poorly controlled diabetes (A1C >8%) in two groups. A geriatric diabetes team assessed barriers and developed strategies to help patients cope with barriers for an intervention group. The control group received equal amounts of attention time. The active intervention was performed for the first 6 months, followed by a “no-contact” period. Outcome measures included A1C, Tinetti test, 6-min walk test (6MWT), self-care frequency, and diabetes-related distress. RESULTS We assessed 100 patients (age 75 ± 5 years, duration 21 ± 13 years, 68% type 2 diabetes, 89% on insulin) over 12 months. After the active period, A1C decreased by −0.45% in the intervention group vs. −0.31% in the control group. At 12 months, A1C decreased further in the intervention group by −0.21% vs. 0% in control group (linear mixed-model, P < 0.03). The intervention group showed additional benefits in scores on measures of self-care (Self-Care Inventory-R), gait and balance (Tinetti), and endurance (6MWT) compared with the control group. Diabetes-related distress improved in both groups. CONCLUSIONS Only attention between clinic visits lowers diabetes-related distress in older adults. However, communication with an educator cognizant of patients’ barriers improves glycemic control and self-care frequency, maintains functionality, and lowers distress in this population

Call me by my name: unravelling the taxonomy of the gulper shark genus Centrophorus in the Mediterranean Sea through an integrated taxonomic approach

The current shift of fishery efforts towards the deep sea is raising concern about the vulnerability of deep-water sharks, which are often poorly studied and characterized by problematic taxonomy. For instance, in the Mediterranean Sea the taxonomy of genus Centrophorus has not been clearly unravelled yet. Since proper identification of the species is fundamental for their correct assessment and management, this study aims at clarifying the taxonomy of this genus in the Mediterranean Basin through an integrated taxonomic approach. We analysed a total of 281 gulper sharks (Centrophorus spp.) collected from various Mediterranean, Atlantic and Indian Ocean waters. Molecular data obtained from cytochrome c oxidase subunit I (COI), 16S ribosomal RNA (16S), NADH dehydrogenase subunit 2 (ND2) and a portion of a nuclear 28S ribosomal DNA gene region (28S) have highlighted the presence of a unique mitochondrial clade in the Mediterranean Sea. The morphometric results confirmed these findings, supporting the presence of a unique and distinct morphological group comprising all Mediterranean individuals. The data strongly indicate the occurrence of a single Centrophorus species in the Mediterranean, ascribable to C. cf. uyato, and suggest the need for a revision of the systematics of the genus in the area

Microvesicles And Their Roles In Early Development

Mouse embryonic stem (ES) cells generate and shed small, vesicular structures from their plasma membranes. These microvesicles (MVs) have emerged as a novel form of intercellular communication with important roles in a variety of biological and pathological processes. Here, I show that ES cells, which are derived from the inner cell mass (ICM) of a blastocyst, communicate with the surrounding layer of trophoblasts using MVs. Two extracellular matrix proteins, fibronectin and laminin, were found to be major protein cargo in these MVs and were shown to interact with integrins expressed on the surfaces of trophoblasts. This resulted in the activation of the signaling proteins FAK and JNK and increased the ability of the trophoblasts to migrate, a critical step during embryo implantation. In fact, injection of MVs generated by ES cells into blastocysts was sufficient to increase their implantation efficiency, highlighting a novel role for MVs in one of the earliest and most important events in pregnancy. In addition to promoting implantation, trophoblasts are essential for placental formation. Interestingly, I determined that trophoblasts generate and shed MVs similar to ES cells, and that the trophoblast MVs are able to impact the behavior of endothelial cells, the cell type that gives rise to the placental vasculature. For example, when incubated with MVs derived from trophoblasts, endothelial cells undergo tubulation and exhibit enhanced survival under nutrientlimiting conditions. Proteomics performed on the trophoblast MVs revealed that they contained a large percentage of metabolic enzymes. Since placental formation involves the extensive   remodeling and formation of blood vessels, which requires a large amount of energy and biomass, these data suggest that the transfer of metabolic enzymes from the MVs to the endothelial cells is important for promoting this outcome

Enhanced brainstem and cortical encoding of sound during synchronized movement.

Movement to a steady beat has been widely studied as a model of alignment of motor outputs on sensory inputs. However, how the encoding of sensory inputs is shaped during synchronized movements along the sensory pathway remains unknown. To investigate this, we simultaneously recorded brainstem and cortical electro-encephalographic activity while participants listened to periodic amplitude-modulated tones. Participants listened either without moving or while tapping in sync on every second beat. Cortical responses were identified at the envelope modulation rate (beat frequency), whereas brainstem responses were identified at the partials frequencies of the chord and at their modulation by the beat frequency (sidebands). During sensorimotor synchronization, cortical responses at beat frequency were larger than during passive listening. Importantly, brainstem responses were also enhanced, with a selective amplification of the sidebands, in particular at the lower-pitched tone of the chord, and no significant correlation with electromyographic measures at tapping frequency. These findings provide first evidence for an online gain in the cortical and subcortical encoding of sounds during synchronized movement, selective to behavior-relevant sound features. Moreover, the frequency-tagging method to isolate concurrent brainstem and cortical activities even during actual movements appears promising to reveal coordinated processes along the human auditory pathway

Peut-on favoriser l’inclusion sociale des jeunes par l’utilisation des médias sociaux?

Les jeunes présentant une déficience intellectuelle (DI) vivent souvent de l’exclusion sociale. Ils semblent avoir un réseau d’amis très restreint, surtout à la fin de leur scolarisation. Or, l’utilisation des technologies de l’information et de la communication (TIC), et notamment celle des médias sociaux, favorise la participation sociale et le développement de liens familiaux ou amicaux. Les jeunes qui présentent une DI profitent-ils de cette technologie? Les TIC permettent-elles à ces jeunes de bénéficier d’un meilleur réseau de soutien personnel et social? Cette recension des écrits tente de répondre à cette question, et révèle que : 1) les TIC ne sont pas accessibles pour tous; et 2) l’utilisation des médias sociaux augmente les risques d’abus et de cybervictimisation.Youth with an intellectual disability (ID) often experience social exclusion. They appear to have very limited groups of friends, especially after they finish school. However, information and communication technologies (ICT), particularly Internet-based social media, facilitate social participation and the development of family relations and friendships. Do youth living with ID take advantage of this technology? Do social media help provide these young people with larger personal and social support networks? Our literature review, which attempts to answer this question, shows that: 1) ICT are not accessible to everyone and 2) social networking sites increase the risk of abuse and cybervictimisation

Mass spec analysis of E14tg2a_4 microvesicles

<p>A mass spectrometry analysis of E14tg2a.4 embryonic stem cell microvesicles.</p

Religious Identity and the Use of Alcohol and Marijuana in a Sample of Diverse Young Adults

Religious identity and religiosity are associated with a lower risk of alcohol and other substance use among middle and high school students 1-6 . However, less is known about the influence of religion on substance use among diverse young adults (ages 18-25). 1, 7 Methods: The present study compared the rates of binge drinking and marijuana use among religious and non-religious diverse young adults (n=113). Participants were interviewed and asked about their demographic characteristics as well as whether they engaged in binge drinking or marijuana use in the past 30 days. Chi-square tests were used. Results: A significantly greater proportion of non-religious young adults (93%; n=40) used marijuana in the past month as compared to those identifying as religious [74.3%, n=52; x 2 (1, n=113)=6.18, p&lt;.05]. There was no significant difference in the rate of binge drinking among religious (71.4%; n=50) and non-religious (60.5%; n=26) participants. Conclusions: In our sample of diverse young adults, the protective effect of religious identity was more pronounced with respect to marijuana use as compared to binge drinking which may have been due to the legal status of marijuana and other potential moderators including ones related to religiosity.Psychological, Health, and Learning Sciences, Department ofHonors Colleg