Linguistic metaconcepts can improve grammatical understanding in L1 education evidence from a Dutch quasi-experimental study

This is the final version. Available on open access from Public Library of Science via the DOI in this recordData Availability: All relevant data are within the paper and its Supporting Information files. Data can also be found on the OSF repository at: DOI 10.17605/OSF.IO/EGKJD (https://osf.io/egkjd/?view_only=None).This mixed-method quasi-experimental study examined whether metaconceptual grammar teaching impacts on (a) students’ L1 grammatical understanding, (b) their ‘blind’ use of grammatical concepts and (c) their preference of using explicit grammatical concepts over everyday concepts in explaining grammatical problems. Previous research, involving single group pre-postintervention designs, found positive effects for metaconceptual interventions on secondary school students’ grammatical reasoning ability, although a negative side effect seemed to be that some students started using grammatical concepts ‘blindly’ (i.e., in an inaccurate way). While there are thus important clues that metaconceptual grammar teaching may lead to increased grammatical understanding, there is a great need for more robust empirical research. The current study, involving 196 Dutch 14-year old pre-university students, is a methodological improvement of previous work, adopting a switching replications design. Bayesian multivariate analyses indicate medium to large effects from the metaconceptual intervention on students’ grammatical understanding. The study found a similar effect of the intervention on students’ ability to use explicit grammatical concepts over everyday concepts in tackling grammatical problems. No evidence for increased ‘blind’ concept use as a negative byproduct of the intervention was found. Additional qualitative analyses of in-intervention tasks provided further evidence for the effectiveness of metaconceptual interventions, and seemed to indicate that cases of blind concept use, rather than being a negative side effect, might actually be part of a gradual process of students’ growing understanding of grammatical (meta)concepts. We discuss these findings in relation to previous work and conclude that linguistic metaconcepts can improve L1 grammatical understanding.Netherlands Organisation of Scientific Research (NWO

Impaired Brain Dopamine and Serotonin Release and Uptake in Wistar Rats Following Treatment with Carbotplatin

Chemotherapy-induced cognitive impairment, known also as “chemobrain”, is a medical complication of cancer treatment that is characterized by a general decline in cognition affecting visual and verbal memory, attention, complex problem solving skills, and motor function. It is estimated that one-third of patients who undergo chemotherapy treatment will experience cognitive impairment. Alterations in the release and uptake of dopamine and serotonin, central nervous system neurotransmitters that play important roles in cognition, could potentially contribute to impaired intellectual performance in those impacted by chemobrain. To investigate how chemotherapy treatment affects these systems, fast-scan cyclic voltammetry (FSCV) at carbon-fiber microelectrodes was used to measure dopamine and serotonin release and uptake in coronal brain slices containing the striatum and dorsal raphe nucleus, respectively. Measurements were taken from rats treated weekly with selected doses of carboplatin and from control rats treated with saline. Modeling the stimulated dopamine release plots revealed an impairment of dopamine release per stimulus pulse (80% of saline control at 5 mg/kg and 58% at 20 mg/kg) after 4 weeks of carboplatin treatment. Moreover, Vmax, the maximum uptake rate of dopamine, was also decreased (55% of saline control at 5 mg/kg and 57% at 20 mg/kg). Nevertheless, overall dopamine content, measured in striatal brain lysates by high performance liquid chromatography, and reserve pool dopamine, measured by FSCV after pharmacological manipulation, did not significantly change, suggesting that chemotherapy treatment selectively impairs the dopamine release and uptake processes. Similarly, serotonin release upon electrical stimulation was impaired (45% of saline control at 20 mg/kg). Measurements of spatial learning discrimination were taken throughout the treatment period and carboplatin was found to alter cognition. These studies support the need for additional neurochemical and behavioral analyses to identify the underlying mechanisms of chemotherapy-induced cognitive disorders

Adult Raphe-Specific Deletion of Lmx1b Leads to Central Serotonin Deficiency

The transcription factor Lmx1b is essential for the differentiation and survival of central serotonergic (5-HTergic) neurons during embryonic development. However, the role of Lmx1b in adult 5-HTergic neurons is unknown. We used an inducible Cre-LoxP system to selectively inactivate Lmx1b expression in the raphe nuclei of adult mice. Pet1-CreERT2 mice were generated and crossed with Lmx1bflox/flox mice to obtain Pet1-CreERT2; Lmx1bflox/flox mice (which termed as Lmx1b iCKO). After administration of tamoxifen, the level of 5-HT in the brain of Lmx1b iCKO mice was reduced to 60% of that in control mice, and the expression of tryptophan hydroxylase 2 (Tph2), serotonin transporter (Sert) and vesicular monoamine transporter 2 (Vmat2) was greatly down-regulated. On the other hand, the expression of dopamine and norepinephrine as well as aromatic L-amino acid decarboxylase (Aadc) and Pet1 was unchanged. Our results reveal that Lmx1b is required for the biosynthesis of 5-HT in adult mouse brain, and it may be involved in maintaining normal functions of central 5-HTergic neurons by regulating the expression of Tph2, Sert and Vmat2

Afrikaans as Standaard Gemiddelde Europees:Wanneer ‘n lid uit sy taalarea beweeg

A recent trend in the study of Standard Average European is the extraterritorial perspective of examining the extent to which non-European languages have converged with this Sprachbund as a result of contact with one or more of its members. The present article complements this line of research in that it investigates the extent to which a European language has diverged from Standard Average European after leaving the linguistic area. The focus is on Dutch, a nuclear member of the Sprachbund, and Afrikaans, its colonial offshoot. The two languages are compared with respect to twelve of the most distinctive linguistic features of Standard Average European. Afrikaans is found to share ten of them with Dutch, including anticausative prominence and formally distinguished intensifiers and reflexives, and could therefore still be considered a core member of the Sprachbund, despite deviations in the expression of negative pronouns and the grammaticality of external possessor constructions. This relatively low degree of divergence may be attributed to the continuity from Settler Dutch to at least the variety of Afrikaans on which the standard language is based and to the important role that Dutch continued to play in the history of Afrikaans

CSF biochemical correlates of mixed affective states

To evaluate the question of whether “mixed” bipolar disorder is a distinct entity, we compared selected cerebrospinal fluid (CSF) biochemical parameters from patients with bipolar disorder, mixed, to those with mania and major depression. Fourteen patients in each category (DSM-III) were studied with regard to CSF HVA, 5HIAA, sodium, potassium, calcium, and magnesium levels under carefully controlled conditions. CSF HVA, 5HIAA, and sodium were found to be significantly higher in manics than in major depressives. Discriminant analysis of the biochemical variables of the mixed affective group identified two biochemically distinct and clinically different subgroups of seven patients each, one resembling the manic group and the other the major depressive group. These findings suggest that mixed affective states do not exist as a separate entity, but are compsed of two subgroups obtained from the manic and major depressive categories.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66203/1/j.1600-0447.1988.tb06339.x.pd

Mapping alterations to the endogenous elemental distribution within the lateral ventricles and choroid plexus in brain disorders using X-ray fluorescence imaging

The choroid plexus and cerebral ventricles are critical structures for the production of cerebral spinal fluid (CSF) and play an important role in regulating ion and metal transport in the brain, however many aspects of its roles in normal physiology and disease states, such as psychiatric illness, remain unknown. The choroid plexus is difficult to examine in vivo, and in situ ex vivo, and as such has typically been examined indirectly with radiolabeled tracers or ex vivo stains, making measurements of the endogenous K+, Cl-, and Ca+ distributions unreliable. In the present study, we directly examined the distribution of endogenous ions and biologically relevant transition metals in the choroid plexus and regions surrounding the ventricles (ventricle wall, cortex, corpus callosum, striatum) using X-ray fluorescence imaging (XFI). We find that the choroid plexus was rich in Cl- and Fe while K+ levels increase further from the ventricle as Cl- levels decrease, consistent with the known role of ion transporters in the choroid plexus CSF production. A polyI:C offspring displayed enlarged ventricles, elevated Cl- surrounding the ventricles, and intraventricular calcifications. These observations fit with clinical findings in patients with schizophrenia and suggest maternal treatment with polyI:C may lead to dysfunctional ion regulation in offspring. This study demonstrates the power of XFI for examining the endogenous elemental distributions of the ventricular system in healthy brain tissue as well as disease models