Search

Schemas are mental representations of common structures of our experience, and they are centrally important to human thinking and memory. Recently, it has been proposed that schemas also play an important role in structuring our imagination of the future. However, tools for automatically measuring the schematic content of written and spoken event narratives are underdeveloped. Here, we report a preliminary investigation into a set of metrics that may differentiate between more and less schematic narratives. Across two experiments, we find that written and spoken narratives that are schema-congruent are more associative, in that they contain words that are more strongly psychologically associated with one another. We discuss how this finding might contribute to the development of tools to automatically measure schematicity in future narratives.

Optical tweezers are tools made of light that enable contactless pushing, trapping, and manipulation of objects, ranging from atoms to space light sails. Since the pioneering work by Arthur Ashkin in the 1970s, optical tweezers have evolved into sophisticated instruments and have been employed in a broad range of applications in the life sciences, physics, and engineering. These include accurate force and torque measurement at the femtonewton level, microrheology of complex fluids, single micro- and nano-particle spectroscopy, single-cell analysis, and statistical-physics experiments. This roadmap provides insights into current investigations involving optical forces and optical tweezers from their theoretical foundations to designs and setups. It also offers perspectives for applications to a wide range of research fields, from biophysics to space exploration.

Reports on differences between remembering the past and imagining the future have led to the hypothesis that constructing future events is a more cognitively demanding process. However, factors that influence these increased demands, such as whether the event has been previously constructed and the types of details comprising the event, have remained relatively unexplored. Across two experiments, we examined how these factors influence the process of constructing event representations by having participants repeatedly construct events and measuring how construction times and a range of phenomenological ratings changed across time points. In Experiment 1, we contrasted the construction of past and future events and found that, relative to past events, the constructive demands associated with future events are particularly heightened when these events are imagined for the first time. Across repeated simulations, future events became increasingly similar to past events in terms of construction times and incorporated detail. In Experiment 2, participants imagined future events involving two memory details (person, location) and then reimagined the event either (a) exactly the same, (b) with a different person, or (c) in a different location. We predicted that if generating spatial information is particularly important for event construction, a change in location will have the greatest impact on constructive demands. Results showed that spatial context contributed to these heightened constructive demands more so than person details, consistent with theories highlighting the central role of spatial processing in episodic simulation. We discuss the findings from both studies in the light of relational processing demands and consider implications for current theoretical frameworks.

Laser threshold magnetometry using the negatively charged nitrogen-vacancy (NV−) centre in diamond as a gain medium has been proposed as a technique to dramatically enhance the sensitivity of room-temperature magnetometry. We experimentally explore a diamond-loaded open tunable fibre-cavity system as a potential contender for the realisation of lasing with NV− centres. We observe amplification of the transmission of a cavity-resonant seed laser at 721 nm when the cavity is pumped at 532 nm and attribute this to stimulated emission. Changes in the intensity of spontaneously emitted photons accompany the amplification, and a qualitative model including stimulated emission and ionisation dynamics of the NV− centre captures the dynamics in the experiment very well. These results highlight important considerations in the realisation of an NV− laser in diamond.

Background: White matter hyperintensities (WMHs) are common in normally functioning older adults. While greater WMH volume may be associated with an increased risk of cognitive dysfunction and dementia, the impact of the location of WMHs is less well understood. We investigated whether WMH burden in specific white matter (WM) tracts is associated with clinical classification and global cognitive scores in at‐risk groups for Alzheimer's disease (AD). Method: Participants from Dementia Prevention Research Clinics, New Zealand, were classified as control, subjective cognitive decline, single‐domain amnestic mild cognitive impairment (MCI), multiple‐domain amnestic MCI, or early AD by a multidisciplinary team (Table 1). Several tract‐WMH "overlap scores" (the percentage of total tract voxels containing WMHs) were calculated for each participant's binarised WMH map (Lesion Segmentation Toolbox, SPM) using seven tract probability templates from a 140‐subject tract atlas (www.megatrackatlas.org). Tract templates were of the superior longitudinal fasciculus (SLF), inferior longitudinal fasciculus (ILF), inferior fronto‐occipital fasciculus (IFOF), uncinate fasciculus (UF), cingulum (CB), fornix, and corpus callosum (CC). Between‐group differences in overlap scores were tested with ANOVAs. Pearson's correlations examined associations between tract‐WMH overlap and global cognitive scores. Result: Figure 1 shows WMH overlap with one tract, the IFOF, in a representative participant. Considering the whole sample, the highest tract‐WMH overlap scores can be seen in the IFOF and CC. Significant between‐group differences were found for the SLF, ILF, IFOF, UF, and CC (p <.05), but not the CB or fornix (Fig. 2), with significant linear trends describing the relationship between overlap scores and clinical classification. Post‐hoc tests confirmed significant pairwise comparisons for overlap scores in all aforementioned tracts except the SLF (Fig. 2). We found Addenbrooke's Cognitive Examination‐III scores negatively correlated with overlap scores in the ILF (r = ‐0.19), IFOF(r = ‐0.22), UF(r = ‐0.22), and CC(r = ‐0.19) (all p <.01), but not the SLF, CB, or fornix (p >.05). Conclusion: Our findings highlight that WMH burden within specific WM tracts is associated with degree of clinical impairment in groups at‐risk of AD. Future research will investigate relationships between overlap scores in specific WM tracts and executive functioning, episodic memory, and processing speed performance. [ABSTRACT FROM AUTHOR]

Aotearoa New Zealand's population is ageing. Increasing life expectancy is accompanied by increases in prevalence of Alzheimer's Disease (AD) and ageing-related disorders. The multicentre Dementia Prevention Research Clinic longitudinal study aims to improve understanding of AD and dementia in Aotearoa, in order to develop interventions that delay or prevent progression to dementia. Comprising research clinics in Auckland, Christchurch and Dunedin, this multi-disciplinary study involves community participants who undergo biennial investigations informed by international protocols and best practice: clinical, neuropsychological, neuroimaging, lifestyle evaluations, APOE genotyping, blood collection and processing. A key research objective is to identify a 'biomarker signature' that predicts progression from mild cognitive impairment to AD. Candidate biomarkers include: blood proteins and microRNAs, genetic, neuroimaging and neuropsychological markers, health, cultural, lifestyle, sensory and psychosocial factors. We are examining a range of mechanisms underlying the progression of AD pathology (e.g. faulty blood–brain barrier, excess parenchymal iron, vascular dysregulation). This paper will outline key aspects of the Dementia Prevention Research Clinic's research, provide an overview of data collection, and a summary of 266 participants recruited to date. The national outreach of the clinics is a strength; the heart of the Dementia Prevention Research Clinics are its people. [ABSTRACT FROM AUTHOR]

Aotearoa New Zealand's population is ageing. Increasing life expectancy is accompanied by increases in prevalence of Alzheimer's Disease (AD) and ageing-related disorders. The multicentre Dementia Prevention Research Clinic longitudinal study aims to improve understanding of AD and dementia in Aotearoa, in order to develop interventions that delay or prevent progression to dementia. Comprising research clinics in Auckland, Christchurch and Dunedin, this multi-disciplinary study involves community participants who undergo biennial investigations informed by international protocols and best practice: clinical, neuropsychological, neuroimaging, lifestyle evaluations, APOE genotyping, blood collection and processing. A key research objective is to identify a 'biomarker signature' that predicts progression from mild cognitive impairment to AD. Candidate biomarkers include: blood proteins and microRNAs, genetic, neuroimaging and neuropsychological markers, health, cultural, lifestyle, sensory and psychosocial factors. We are examining a range of mechanisms underlying the progression of AD pathology (e.g. faulty blood-brain barrier, excess parenchymal iron, vascular dysregulation). This paper will outline key aspects of the Dementia Prevention Research Clinic's research, provide an overview of data collection, and a summary of 266 participants recruited to date. The national outreach of the clinics is a strength; the heart of the Dementia Prevention Research Clinics are its people., Competing Interests: No potential conflict of interest was reported by the author(s)., (© 2022 The Royal Society of New Zealand.)

Recent studies have demonstrated that remembering past experiences and imagining future scenarios recruits a core network including the hippocampus. Even so, constructing future events engages the hippocampus more than remembering past events. This fMRI study examined whether increased hippocampal activity for future events includes both specific and general events. Participants constructed specific and general past and future events during fMRI scanning. We replicated previous findings of increased activity in the right anterior hippocampus when constructing future relative to past events, and when constructing specific relative to general events. Importantly, both effects were driven by a significant interaction between temporal direction and specificity, with specific future events resulting in more activity than other conditions, including general future events. No regions exhibited greater activity during the construction of past relative to future events, or general relative to specific events. These results suggest that the process of constructing a detailed representation of a novel and specific future event differentially engages the right anterior hippocampus compared with other forms of event simulation and recall. Future work is needed to disambiguate the role of encoding, novelty and detail recombination in engaging the right anterior hippocampus during simulation., (Copyright © 2010 Wiley-Liss, Inc.)