Grammaticalization is the process whereby lexical items change into grammatical items. This phenomenon is widely attested, while the change from grammatical to lexical is far less common. We ran two experiments to test whether this unidirectional tendency originates with a preference for extending lexical meanings to grammatical ones rather than vice versa. We focus on body parts and spatial relations. In Experiment 1, participants were told the meaning of an artificial word then rated how likely it is that that word can also be used to refer to a second meaning – one meaning was a body part and one a preposition. We expected higher ratings when extending from body parts to prepositions than vice versa but found no difference. In Experiment 2, participants performed semantic extension in communication. We varied whether they extended words for body parts to prepositions or vice versa. Again, we found no asymmetry. Finally, we used a model of Experiment 2 to show that asymmetrical extension follows straightforwardly if there is an asymmetry in the number of words available relative to the number of meanings to express, indicating that having a larger number of lexical items than grammatical concepts could be an alternative source of unidirectionality.

Most older adults prefer to age in place, which for many will require home and community care (HCC) support. Unfortunately, HCC capacity is insufficient to meet demand due in part to low wages, particularly for personal support workers (PSWs) who provide the majority of paid care. Using Ontario as a case study, this paper estimates the cost and capacity impacts of implementing wage parity between PSWs employed in HCC and institutional long-term care (ILTC). Specifically, we consider the cost of increased HCC PSW wages versus expected savings from avoiding unnecessary ILTC placement for those accommodated by HCC capacity growth. The expected increase in HCC PSW retention would create HCC capacity for approximately 160,000 people, reduce annual health system costs by approximately $7 billion, and provide an 88 per cent return on investment. Updating wage structures to reduce turnover and enable HCC capacity growth is a cost-efficient option for expanding health system capacity.

Previous research has shown that non-Māori Speaking New Zealanders have extensive latent knowledge of Māori, despite not being able to speak it. This knowledge plausibly derives from a memory store of Māori forms (Oh et al., 2020; Panther et al., 2023). Modelling suggests that this ‘proto-lexicon’ includes not only Māori words, but also word-parts; however, this suggestion has not yet been tested experimentally.

We present the results of a new experiment in which non-Māori speaking New Zealanders and non-New Zealanders were asked to segment a range of Māori words into parts. We show that the degree to which segmentations of non-Māori speakers correlate to the segmentations of two fluent speakers of Māori is stronger among New Zealanders than non-New Zealanders. This research adds to the growing evidence that even in a largely ‘monolingual’ population, there is evidence of latent bilingualism through long-term exposure to a second language.

This work presents a detailed, orbitally tuned biogenic silica record of continental paleoclimate change during the Brunhes chron. The Brunhes/Matuyama boundary lies within the warm isotopic stage 19 in Baikal, and the boundaries between eight lithological cycles correspond to terminations in the marine oxygen isotope record. The high amplitude and resolution of climatically driven changes in BioSi content in Lake Baikal sediments permits tuning of almost every precessional cycle during the Brunhes and reveals the structure of interglacial stages. For example, the last three interglacial stages (MIS 5, 7, and 9) clearly consist of five substages (a, b, c, d, e) corresponding to precessional insolation peaks. Abrupt and intense regional glaciations in Siberia during substages 5d and 7d were driven by extreme insolation minima. During substage 9d cooling was more gradual in response to more moderate forcing. The impact of strong glaciation is also observed in the middle of stage 15, where full glacial conditions appear to have lasted for over 30,000 yr during substages 15d, 15c, and 15b. Marine oxygen isotopic stage 11 appears to be the warmest period during the Brunhes in the Lake Baikal record, with at least three substages.

A new hypothesis is presented regarding the response of the Lake Baikal BioSi record to insolation forcing. Based on the mechanism controlling modern diatom blooms, biogenic silica production is hypothesized to be dependent on changes in the heat balance of the lake and consequently on changes in the thermal structure of the water column. This mechanism is also sensitive to short-term sub-Milankovich cooling events, such as the mid-Eemian cooling, the Montaigu event during substage 5c, and a cooling which appears to be analogous to the Montaigu event during substage 9c. The continuity of the Lake Baikal paleoclimate record, its sensitivity to orbital forcing, and its high resolution make it an excellent candidate for a new “paleoclimatic stratotype” section for continental Asia.

There is increasing evidence that hyperenergetic diets have an impact on memory in rodents. However, it is largely unknown how diets, such as a cafeteria diet (CD), that mimic a Western-type diet act on learning and memory, in particular when fed during early stages of development. Here, we fed lactating dams a CD and exposed both male and female offspring to a novel object discrimination (NOD) task, a two-trial test of recognition memory in which rats exposed to two identical objects during a training/familiarisation trial can discriminate a novel from a familiar object during the subsequent choice trial. The choice trial was performed following inter-trial interval (ITI) delays of up to 4 h. Maternal diet did not have an impact on exploration of the objects by either sex during the familiarisation trial. Control males discriminated the novel from the familiar object, indicating intact memory with an ITI of 1 h, but not 2 or 4 h. The CD delayed this natural forgetting in male rats such that discrimination was also evident after a 2 h ITI. In contrast, control females exhibited discrimination following both 1 and 2 h ITI, but the CD impaired performance. In summary, the present study shows that maternal exposure to the CD programmes NOD in the adult. In better-performing females, dietary programming interferes with NOD, whereas NOD was improved in males after lactational CD feeding.

Objective: Very few studies have examined permanent post-concussion symptoms (PCSs) after mild traumatic brain injury (MTBI). None have reported the nature of such symptoms. Our recent study was the first to report on a wide range of factors affecting PCSs in a representative sample of such patients. This paper presents the frequencies of the different PCSs experienced by this group and compares them with PCSs at earlier stages post injury.

Method: One hundred consecutively referred patients to a Community Head Injury Service in Buckinghamshire, UK, for the treatment of long-term PCSs after MTBI were invited to participate in the original study. Those consenting to do so (n = 24, mean time post injury = 6.9 years) completed a Rivermead Post Concussion Symptoms Questionnaire. The frequency of the types of symptoms reported is presented. These are then contrasted with comparable PCS presentations at 7–10 days and 6 months post injury from two other studies.

Results: Fatigue was reported by all long-term patients. Poor concentration, sleep disturbance, taking longer to think and irritability were the other most frequently endorsed permanent symptoms. The least reported were blurred/double vision, photophobia, nausea, headache and dizziness. A similar pattern was present in those at earlier stages post injury.

Conclusions: The most common permanent PCSs may be those best conceptualised as the more cognitively and emotionally based symptoms, and the least common the more somatically based ones. There may be some consistency in the nature of PCSs reported over time.