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We investigated the development of phonological awareness and reading abilities in French-speaking children aged 5 - 12 years. Participants were divided into seven groups (kindergarten to grade 6). Metaphonological tasks included segmentation, blending and inversion at the syllable and the phoneme level, reading of regular and irregular words and nonwords, rhyme production and rhyme recognition. We hypothesised that: (1) children will rely more heavily on phonological awareness in the first years of reading acquisition; (2) development of phonological awareness at the phoneme level will facilitate reading of regular words and nonwords. Results in metaphonological tasks showed a clear developmental progression between kindergarten and 2nd grade. Regular words were easily read in grade 2, nonwords were adequately decoded in grade 3, whereas irregular word reading gradually increased until grade 6 and beyond. These results suggest that the facilitatory effect between phonological awareness and reading appears to be limited to the phoneme unit. [ABSTRACT FROM AUTHOR]

In order to evaluate the possible consequences of temporal lobe epilepsy on reading acquisition, we first compared the reading skills and phonological awareness abilities in a set of 13-year-old identical twins, one of whom is affected by temporal lobe epilepsy (LB). We then compared their performances to those of an age- and IQ-matched control group. Both siblings have an intellectual quotient above average as well as normal memory and linguistic abilities. Results showed that the reading age of LB (assessed by the Lefabvrais French reading test) was more than two years behind expectations whereas that of her sister was above average. Further, in contrast to her sister and healthy control subjects, LB exhibited specific deficits in elaborate metaphonological awareness abilities (non-word repetition, rhyme production, phonemic segmentation and syllabic inversion). These could be linked to temporal lobe dysfunction, thus confirming the important role of the temporal lobes in reading acquisition. [ABSTRACT FROM AUTHOR]

CACNA1A deletions cause epilepsy, ataxia, and a range of neurocognitive deficits, including inattention, impulsivity, intellectual deficiency and autism. To investigate the underlying mechanisms, we generated mice carrying a targeted Cacna1a deletion restricted to parvalbumin-expressing (PV) neurons (PV Cre ;Cacna1a c/+ ) or to cortical pyramidal cells (PC) (Emx1 Cre ;Cacna1a c/+ ). GABA release from PV-expressing GABAergic interneurons (PV-INs) is reduced in PV Cre ;Cacna1a c/+ mutants, resulting in impulsivity, cognitive rigidity and inattention. By contrast, the deletion of Cacna1a in PCs does not impact cortical excitability or behaviour in Emx1 Cre ;Cacna1a c/+ mutants. A targeted Cacna1a deletion in the orbitofrontal cortex (OFC) results in reversal learning deficits while a medial prefrontal cortex (mPFC) deletion impairs selective attention. These deficits can be rescued by the selective chemogenetic activation of cortical PV-INs in the OFC or mPFC of PV Cre ;Cacna1a c/+ mutants. Thus, Cacna1a haploinsufficiency disrupts perisomatic inhibition in frontal cortical circuits, leading to a range of potentially reversible neurocognitive deficits., (© 2021. The Author(s), under exclusive licence to Springer Nature Limited.)

As part of a presurgical investigation for a resection of a tumor located in the left temporal brain region, we evaluated pre- and postsurgical language lateralization in a right-handed boy with refractory epilepsy. In this study, we compared functional near infrared spectroscopy (fNIRS) results obtained while the participant performed expressive and receptive language tasks with those obtained using functional magnetic resonance imaging (fMRI). This case study illustrates the potential for NIRS to contribute favorably to the localization of language functions in children with epilepsy and cognitive or behavioral problems and its potential advantages over fMRI in presurgical assessment. Moreover, it suggests that fNIRS is sensitive in localizing an atypical language network or potential brain reorganization related to epilepsy in young patients.

CACNA1A loss-of-function mutations classically present as episodic ataxia type 2 (EA2), with brief episodes of ataxia and nystagmus, or with progressive spinocerebellar ataxia (SCA6). A minority of patients carrying CACNA1A mutations develops epilepsy. Non-motor symptoms associated with these mutations are often overlooked. In this study, we report 16 affected individuals from four unrelated families presenting with a spectrum of cognitive impairment including intellectual deficiency, executive dysfunction, ADHD and/or autism, as well as childhood-onset epileptic encephalopathy with refractory absence epilepsy, febrile seizures, downbeat nystagmus and episodic ataxia. Sequencing revealed one CACNA1A gene deletion, two deleterious CACNA1A point mutations including one known stop-gain and one new frameshift variant and a new splice-site variant. This report illustrates the phenotypic heterogeneity of CACNA1A loss-of-function mutations and stresses the cognitive and epileptic manifestations caused by the loss of CaV2.1 channels function, presumably affecting cerebellar, cortical and limbic networks.

Although children with epilepsy tend to exhibit more reading difficulties than their classmates, no systematic studies have investigated the relationship between these difficulties and epilepsy. As functional neuroimaging studies have implicated both temporal and frontal lobes in the phonological aspect of reading [K.R. Pugh, B.A. Shaywitz, S.E. Shaywitz, et al. Brain 1996;119:1221-38], seizure activity originating in either region could interfere with phonological processing, whereas generalized seizures would not disturb this function as much. To explore this hypothesis, we compared the metaphonological skills of school-aged children with either temporal lobe epilepsy (TLE), frontal lobe epilepsy (FLE), or generalized absence seizures (ABS) with those of healthy controls. While the reading ability of all epileptic children was close to 2 years behind expectations, children with TLE did not differ from the controls on phonological tasks. In contrast, children with FLE exhibited significant deficits, whereas children with ABS showed difficulties restricted to phonemic segmentation. The results suggest that FLE and, to a lesser extent, generalized seizures may interfere with phonological processing, whereas TLE may affect other aspects of reading.

Recent studies do not agree on the possible relationship between medical conditions and traffic safety; most of them do not control for exposure factors. In this study, we estimate the effect of binocular vision problems on taxi drivers' distributions of crashes (frequency). Moreover, given a crash, we estimate the effect of binocular vision problems on the distributions of the number of victims per crash (dead or injured). Our data and models permit the simultaneous consideration of many variables: age, medical condition, exposure factors measured by distance driven and time behind the wheel, qualitative risk factors, other characteristics of the driver, and crash circumstances in the models for the number of victims. Results show that taxi drivers have a large average number of crashes per year, larger for those with binocular vision problems compared with healthy ones, but not more severe in terms of the number of victims. The driver's past record (number of crashes and demerit points in the previous year) is a significant predictor of the number of crashes. Age is associated significantly with the number and the severity of crashes with older drivers having a better record than the youngest group (30 years old or less).

In this research we studied the association between commercial motor vehicle drivers' medical conditions and crash severity. Some aspects of medical condition were considered. To our knowledge, no study has ever isolated this association. The severity of a crash was measured by the total number of victims (injured and dead). We estimated nonlinear regression models (specifically, Poisson and negative binomial) which incorporated, simultaneously, information on drivers' characteristics, crash circumstances and health status, in order to isolate the association between health status and crash severity. Our results show that crashes of truck drivers with binocular vision problems and bus drivers with hypertension are more severe than those of healthy drivers. No other medical condition considered in this study was significantly associated with crash severity. Many variables describing crash circumstances were also significant.

An epizootic of bovine mastitis caused by a nontuberculous mycobacterial agent occurred in a large Quebec dairy herd. This mastitis problem was characterized by the occurrence of a high number of cows with severely inflamed, indurated and therapeutically incurable quarters. Routine diagnostic laboratory methods yielded negative cultural findings. Approximately 40% of the milking cows developed chronic mastitis. Poor sanitation, improper milking procedures and a faulty milking system prevailed at that time.