On the Acquisition of Polarity Items: 11- to 12-Year-Olds' Comprehension of German NPIs and PPIs

Existing work on the acquisition of polarity-sensitive expressions (PSIs) suggests that children show an early sensitivity to the restricted distribution of negative polarity items (NPIs), but may be delayed in the acquisition of positive polarity items (PPIs). However, past studies primarily targeted PSIs that are highly frequent in children’s language input. In this paper, we report an experimental investigation on children’s comprehension of two NPIs and two PPIs in German. Based on corpus data indicating that the four tested PSIs are present in child-directed speech but rare in young children’s utterances, we conducted an auditory rating task with adults and 11- to 12-year-old children. The results demonstrate that, even at 11–12 years of age, children do not yet show a completely target-like comprehension of the investigated PSIs. While they are adult-like in their responses to one of the tested NPIs, their responses did not demonstrate a categorical distinction between licensed and unlicensed PSI uses for the other tested expressions. The effect was led by a higher acceptance of sentences containing unlicensed PSIs, indicating a lack of awareness for their distributional restrictions. The results of our study pose new questions for the developmental time scale of the acquisition of polarity items.

STED super-resolution imaging of membrane packing and dynamics by exchangeable polarity-sensitive dyes

Understanding the plasma membrane nano-scale organisation and dynamics in living cells requires microscopy techniques with high temporal and spatial resolution and long acquisition times, that also allow for the quantification of membrane biophysical properties such as lipid ordering. Among the most popular super-resolution techniques, stimulated emission depletion (STED) microscopy offers one of the highest temporal resolution, ultimately defined by the scanning speed. However, monitoring live processes using STED microscopy is significantly limited by photobleaching, which recently has been circumvented by exchangeable membrane dyes that only temporarily reside in the membrane. Here, we show that NR4A, a polarity-sensitive exchangeable plasma membrane probe based on Nile Red, permits the super-resolved quantification of membrane biophysical parameters in real time with high temporal and spatial resolution as well as long acquisition times. The potential of this polarity-sensitive exchangeable dyes is showcased by live-cell real-time 3D-STED recordings of bleb formation and lipid exchange during membrane fusion, as well as by STED-fluorescence correlation spectroscopy (STED-FCS) experiments for the simultaneous quantification of membrane dynamics and lipid packing, which correlate in model and live-cell membranes.

Issues in the Syntax of Polarity-Sensitive Items

This chapter provides an overview of PSIs (polarity-sensitive items) in Arabic and briefly outlines the critical issues in the syntax of PSIs in Arabic and their contributions to Arabic syntax and linguistic theory. It also outlines the theoretical underpinnings of research on Arabic negation, relying on the author’s most recent publications. The author synthesizes the major and crucial findings from cross-linguistic studies on this topic and studies of PSIs in Arabic. This chapter also articulates the critical issues, methodology, and scope of content. A quick overview of polarity sensitivity reveals much of the microvariation in Arabic. Geographically, this variation comparatively grows at the phonetic, morphological, and lexical levels, moving from the west with the Moroccan dialect, into Egyptian and Jordanian along the Mediterranean, into the Arabian Peninsula with Qatari Arabic, and into the formal written Arabic.

PSIs with Head-Like Properties

This chapter discusses two main issues that arise from PSIs (polarity-sensitive items) with head-like properties. These PSIs seem to be outside the (immediate) domain of their licensor. The first issue is how these PSIs are licensed in syntax and how a unified analysis can handle their distribution. The author argues that these PSIs are adverbial phrases that do not project a clausal projection and that negation licenses these PSIs either in Spec-NegP or under c-command. This unified analysis does not appeal to the problematic head–complement relation as a putative licensing configuration. Another issue that arises from these NPIs (negative polarity items) with head-like properties is their ability to host clitics with accusative and genitive case marking. This issue raises interesting questions pertaining to case theory and dependent case licensing. The author argues that negation licenses the puzzling accusative case of the pronominal complement, a conclusion with far-reaching implications to dependent case licensing in natural language.