Poor neural and perceptual phoneme discrimination during acoustic variation in dyslexia

Whereas natural acoustic variation in speech does not compromise phoneme discrimination in healthy adults, it was hypothesized to be a challenge for developmental dyslexics. We investigated dyslexics’ neural and perceptual discrimination of native language phonemes during acoustic variation. Dyslexics and non-dyslexics heard /æ/ and /i/ phonemes in a context with fo variation and then in a context without it. Mismatch negativity (MMN) and P3a responses to phoneme changes were recorded with electroencephalogram to compare groups during ignore and attentive listening. perceptual phoneme discrimination in the variable context was evaluated with hit-ratios and reaction times. MMN/N2bs were diminished in dyslexics in the variable context. Hit-ratios were smaller in dyslexics than controls. MMNs did not differ between groups in the context without variation. These results suggest that even distinctive vowels are challenging to discriminate for dyslexics when the context resembles natural variability of speech. This most likely reflects poor categorical perception of phonemes in dyslexics. Difficulties to detect linguistically relevant invariant information during acoustic variation in speech may contribute to dyslexics’ deficits in forming native language phoneme representations during infancy. Future studies should acknowledge that simple experimental paradigms with repetitive stimuli can be insensitive to dyslexics’ speech processing deficits.Peer reviewe

Hermon ärtyvyyden määrittäminen threshold tracking -menetelmällä

Tiivistelmä. Tunnetummilla kliinisen neurofysiologian tutkimuksilla, kuten elektroneuromyografialla (ENMG) saadaan tietoa hermosolujen johtumisnopeuksista ja hermojen eristekerroksesta eli myeliinikuoresta. Threshold tracking -menetelmässä määritetään puolestaan hermon ärtyvyyttä, eli määritetään kynnyspotentiaali, joka vaaditaan aktiopotentiaalin muodostumiseen. Threshold tracking -menetelmällä voidaan tutkia sekä sensorisia että motorisia neuroneita. Tässä kandidaatin tutkielmassa käsitellään hermosolun biofysiikkaa, noninvasiivista mittausmenetelmää ja threshold tracking -menetelmällä tapahtuvaa mittausta. Hermosolun biofysiikassa käsitellään sensorista ja motorista neuronia, solukalvon toimintaa ja ionikanavien funktiota aktiopotentiaalissa. Threshold tracking -menetelmästä perehdytään mittauslaitteistoon, mittausperiaatteeseen ja erilaisiin mittauskonfiguraatioihin

Gastric ulcers in 7 8-week-old pigs, fed by various formulae of pelleted feed

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Infancy and early childhood maturation of neural auditory change detection and its associations to familial dyslexia risk

Objective: We investigated early maturation of the infant mismatch response MMR, including mismatch negativity (MMN), positive MMR (P-MMR), and late discriminative negativity (LDN), indexing auditory discrimination abilities, and the influence of familial developmental dyslexia risk. Methods: We recorded MMRs to vowel, duration, and frequency deviants in pseudo-words at 0, 6, and 28 months and compared MMRs in subgroups with vs. without dyslexia risk, in a sample overrepresented by risk infants. Results: Neonatal MMN to the duration deviant became larger and earlier by 28 months; MMN was elicited by more deviants only at 28 months. The P-MMR was predominant in infancy; its amplitude increased by 6 and decreased by 28 months; latency decreased with increasing age. An LDN emerged by 6 months and became larger and later by 28 months. Dyslexia risk affected MMRs and their maturation. Conclusions: MMRs demonstrate an expected maturational pattern with 2-3 peaks by 28 months. The effects of dyslexia risk are prominent but not always as expected. Significance: This large-scale longitudinal study shows MMR maturation with three age groups and three deviants. Results illuminate MMR's relation to the adult responses, and hence their cognitive underpinnings, and help in identifying typical/atypical auditory development in early childhood. (c) 2022 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).Peer reviewe

The three mouse actin-depolymerizing factor/cofilins evolved to fulfill cell-type-specific requirements for actin dynamics

Actin-depolymerizing factor (ADF)/cofilins are essential regulators of actin filament turnover. Several ADF/cofilin isoforms are found in multicellular organisms, but their biological differences have remained unclear. Herein, we show that three ADF/cofilins exist in mouse and most likely in all other mammalian species. Northern blot and in situ hybridization analyses demonstrate that cofilin-1 is expressed in most cell types of embryos and adult mice. Cofilin-2 is expressed in muscle cells and ADF is restricted to epithelia and endothelia. Although the three mouse ADF/cofilins do not show actin isoform specificity, they all depolymerize platelet actin filaments more efficiently than muscle actin. Furthermore, these ADF/cofilins are biochemically different. The epithelial-specific ADF is the most efficient in turning over actin filaments and promotes a stronger pH-dependent actin filament disassembly than the two other isoforms. The muscle-specific cofilin-2 has a weaker actin filament depolymerization activity and displays a 5-10-fold higher affinity for ATP-actin monomers than cofilin-1 and ADF. In steady-state assays, cofilin-2 also promotes filament assembly rather than disassembly. Taken together, these data suggest that the three biochemically distinct mammalian ADF/cofilin isoforms evolved to fulfill specific requirements for actin filament dynamics in different cell types

Actitudes de los trabajadores frente a los programas de promoción de la salud para la prevención del cáncer en el lugar del trabajo

SummaryObjetiveWe describe a method for feasibility assessment of workplace health promotion (WHP) programs as a necessary prerequisite of any WHP program.MethodsA total of 167 employees from five workplace communities participated in the study. A questionnaire on the basic components of feasibility (risk factors, attitudes to workplace health promotion interventions, and social-occupational context) was administered.ResultsRisk behaviours were common among the employees interviewed. Health promotion in the workplace was favorably viewed by 79% of subjects but reported participation would be lower. Interventions on diet and physical activity received the highest acceptance. Participation would be greatest among local administration employees.ConclusionsThe method demonstrated its utility in obtaining useful data for designing workplace health promotion interventions

Infant event-related potentials to speech are associated with prelinguistic development

Neural auditory processing and prelinguistic communication build the foundation for later language development, but how these two are associated is not well known. The current study investigated how neural speech processing is associated with the level and development of prelinguistic skills in 102 infants. We recorded event-related potentials (ERPs) in 6-months-olds to assess the neural detection of a pseudoword (obligatory responses), as well as the neural discrimination of changes in the pseudoword (mismatch responses, MMRs). Prelinguistic skills were assessed at 6 and 12 months of age with a parental questionnaire (Infant-Toddler Checklist). The association between the ERPs and prelinguistic skills was examined using latent change score models, a method specifically constructed for longitudinal analyses and explicitly modeling intra-individual change. The results show that a large obligatory P1 at 6 months of age predicted strong improvement in prelinguistic skills between 6 and 12 months of age. The MMR to a frequency change was associated with the concurrent level of prelinguistic skills, but not with the improvement of the skills. Overall, our results highlight the strong association between ERPs and prelinguistic skills, possibly offering opportunities for early detection of atypical linguistic and communicative development.Peer reviewe

Parity nonconserving cold neutron-parahydrogen interactions

Three pion dominated observables of the parity nonconserving interactions between the cold neutrons and parahydrogen are calculated. The transversely polarized neutron spin rotation, unpolarized neutron longitudinal polarization, and photon-asymmetry of the radiative polarized neutron capture are considered. For the numerical evaluation of the observables, the strong interactions are taken into account by the Reid93 potential and the parity nonconserving interactions by the DDH model along with the two-pion exchange.Comment: 17 pages, 2 figure