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2.
Memory ; 32(4): 431-448, 2024 Apr.
Article En | MEDLINE | ID: mdl-38557252

Remembering life experiences involves recalling not only what occurred (episodic details), but also where an event took place (spatial context), both of which decline with age. Although spatial context can cue episodic detail recollection, it is unknown whether initially recalling an event alongside greater reinstatement of spatial context protects memory for episodic details in the long term, and whether this is affected by age. Here, we analysed 1079 personally-experienced, real-world events from 29 older adults and 12 younger adults. Events were recalled first on average 6 weeks after they occurred and then again on average 24 weeks after they occurred. We developed a novel scoring protocol to quantify spatial contextual details and used the established Autobiographical Interview to quantify episodic details. We found improved recall of episodic details after a delay if those details had initially been recalled situated in greater spatial context. Notably, for both older and younger adults, this preservation was observed for memories initially recalled with low, but not high, numbers of episodic details, suggesting that spatial context aided episodic retrieval for memories that required more support. This work supports the notion that spatial context scaffolds detail-rich event recollection and inspires memory interventions that leverage this spatial scaffold.


Memory, Episodic , Mental Recall , Humans , Male , Female , Young Adult , Aged , Adult , Aging/psychology , Middle Aged , Age Factors , Cues , Adolescent
3.
Elife ; 132024 Apr 22.
Article En | MEDLINE | ID: mdl-38647143

Combining information from multiple senses is essential to object recognition, core to the ability to learn concepts, make new inferences, and generalize across distinct entities. Yet how the mind combines sensory input into coherent crossmodal representations - the crossmodal binding problem - remains poorly understood. Here, we applied multi-echo fMRI across a 4-day paradigm, in which participants learned three-dimensional crossmodal representations created from well-characterized unimodal visual shape and sound features. Our novel paradigm decoupled the learned crossmodal object representations from their baseline unimodal shapes and sounds, thus allowing us to track the emergence of crossmodal object representations as they were learned by healthy adults. Critically, we found that two anterior temporal lobe structures - temporal pole and perirhinal cortex - differentiated learned from non-learned crossmodal objects, even when controlling for the unimodal features that composed those objects. These results provide evidence for integrated crossmodal object representations in the anterior temporal lobes that were different from the representations for the unimodal features. Furthermore, we found that perirhinal cortex representations were by default biased toward visual shape, but this initial visual bias was attenuated by crossmodal learning. Thus, crossmodal learning transformed perirhinal representations such that they were no longer predominantly grounded in the visual modality, which may be a mechanism by which object concepts gain their abstraction.


Magnetic Resonance Imaging , Temporal Lobe , Humans , Temporal Lobe/physiology , Temporal Lobe/diagnostic imaging , Female , Male , Adult , Young Adult , Auditory Perception/physiology , Learning/physiology , Visual Perception/physiology , Photic Stimulation , Acoustic Stimulation , Brain Mapping , Perirhinal Cortex/physiology
5.
New Phytol ; 242(2): 351-371, 2024 Apr.
Article En | MEDLINE | ID: mdl-38416367

Tropical forest root characteristics and resource acquisition strategies are underrepresented in vegetation and global models, hampering the prediction of forest-climate feedbacks for these carbon-rich ecosystems. Lowland tropical forests often have globally unique combinations of high taxonomic and functional biodiversity, rainfall seasonality, and strongly weathered infertile soils, giving rise to distinct patterns in root traits and functions compared with higher latitude ecosystems. We provide a roadmap for integrating recent advances in our understanding of tropical forest belowground function into vegetation models, focusing on water and nutrient acquisition. We offer comparisons of recent advances in empirical and model understanding of root characteristics that represent important functional processes in tropical forests. We focus on: (1) fine-root strategies for soil resource exploration, (2) coupling and trade-offs in fine-root water vs nutrient acquisition, and (3) aboveground-belowground linkages in plant resource acquisition and use. We suggest avenues for representing these extremely diverse plant communities in computationally manageable and ecologically meaningful groups in models for linked aboveground-belowground hydro-nutrient functions. Tropical forests are undergoing warming, shifting rainfall regimes, and exacerbation of soil nutrient scarcity caused by elevated atmospheric CO2. The accurate model representation of tropical forest functions is crucial for understanding the interactions of this biome with the climate.


Las características de las raíces de los bosques tropicales y las estrategias de adquisición de recursos están subrepresentadas en modelos de vegetación, lo que dificulta la predicción del efecto de cambio de clima para estos ecosistemas ricos en carbono. Los bosques tropicales a menudo tienen combinaciones únicas a nivel mundial de alta biodiversidad taxonómica y funcional, estacionalidad de precipitación, y suelos infértiles, dando lugar a patrones distintos en los rasgos y funciones de las raíces en comparación con los ecosistemas de latitudes más altas. Integramos los avances recientes en nuestra comprensión de la función subterránea de los bosques tropicales en modelos de vegetación, centrándonos en la adquisición de agua y nutrientes. Ofrecemos comparaciones de avances recientes en la comprensión empírica y de modelos de las características de las raíces que representan procesos funcionales importantes en los bosques tropicales. Nos centramos en: (1) estrategias de raíces finas para adquisición de recursos del suelo, (2) acoplamiento y compensaciones entre adquisición del agua y de nutrientes, y (3) vínculos entre funciones sobre tierra y debajo del superficie en bosques tropicales. Sugerimos vías para representar estas comunidades de plantas extremadamente diversas en grupos computacionalmente manejables y ecológicamente significativos en modelos. Los bosques tropicales se están calentando, tienen cambios en los regímenes de lluvias, y tienen una exacerbación de la escasez de nutrientes del suelo causada por el elevado CO2 atmosférico. La representación precisa de las funciones de los bosques tropicales en modelos es crucial para comprender las interacciones de este bioma con el clima.


Ecosystem , Plant Roots , Nitrogen , Forests , Soil , Plants , Water , Tropical Climate , Trees
6.
Proc Natl Acad Sci U S A ; 120(48): e2301642120, 2023 Nov 28.
Article En | MEDLINE | ID: mdl-37983511

Science is among humanity's greatest achievements, yet scientific censorship is rarely studied empirically. We explore the social, psychological, and institutional causes and consequences of scientific censorship (defined as actions aimed at obstructing particular scientific ideas from reaching an audience for reasons other than low scientific quality). Popular narratives suggest that scientific censorship is driven by authoritarian officials with dark motives, such as dogmatism and intolerance. Our analysis suggests that scientific censorship is often driven by scientists, who are primarily motivated by self-protection, benevolence toward peer scholars, and prosocial concerns for the well-being of human social groups. This perspective helps explain both recent findings on scientific censorship and recent changes to scientific institutions, such as the use of harm-based criteria to evaluate research. We discuss unknowns surrounding the consequences of censorship and provide recommendations for improving transparency and accountability in scientific decision-making to enable the exploration of these unknowns. The benefits of censorship may sometimes outweigh costs. However, until costs and benefits are examined empirically, scholars on opposing sides of ongoing debates are left to quarrel based on competing values, assumptions, and intuitions.


Censorship, Research , Science , Social Responsibility , Costs and Cost Analysis
7.
Behav Brain Sci ; 46: e382, 2023 11 14.
Article En | MEDLINE | ID: mdl-37961773

We highlight recent progress in neuroimaging and neuropsychological research on memory mechanisms in the medial temporal lobe that speaks to the involuntary nature of memory retrieval processes. We suggest that evidence form these studies supports Barzykowski and Moulin's proposal that memory signals involved in experiences of familiarity and déjà vu can be generated in the absence of retrieval intentionality.


Deja Vu , Temporal Lobe , Humans , Deja Vu/psychology , Memory , Recognition, Psychology , Neuroimaging
8.
Ecol Lett ; 26(11): 1829-1839, 2023 Nov.
Article En | MEDLINE | ID: mdl-37807917

Tropical rainforest woody plants have been thought to have uniformly low resistance to hydraulic failure and to function near the edge of their hydraulic safety margin (HSM), making these ecosystems vulnerable to drought; however, this may not be the case. Using data collected at 30 tropical forest sites for three key traits associated with drought tolerance, we show that site-level hydraulic diversity of leaf turgor loss point, resistance to embolism (P50 ), and HSMs is high across tropical forests and largely independent of water availability. Species with high HSMs (>1 MPa) and low P50 values (< -2 MPa) are common across the wet and dry tropics. This high site-level hydraulic diversity, largely decoupled from water stress, could influence which species are favoured and become dominant under a drying climate. High hydraulic diversity could also make these ecosystems more resilient to variable rainfall regimes.


Ecosystem , Trees , Tropical Climate , Forests , Wood , Droughts , Plant Leaves , Xylem
9.
Annu Rev Vis Sci ; 9: 409-434, 2023 09 15.
Article En | MEDLINE | ID: mdl-37068791

Perception and memory are traditionally thought of as separate cognitive functions, supported by distinct brain regions. The canonical perspective is that perceptual processing of visual information is supported by the ventral visual stream, whereas long-term declarative memory is supported by the medial temporal lobe. However, this modular framework cannot account for the increasingly large body of evidence that reveals a role for early visual areas in long-term recognition memory and a role for medial temporal lobe structures in high-level perceptual processing. In this article, we review relevant research conducted in humans, nonhuman primates, and rodents. We conclude that the evidence is largely inconsistent with theoretical proposals that draw sharp functional boundaries between perceptual and memory systems in the brain. Instead, the weight of the empirical findings is best captured by a representational-hierarchical model that emphasizes differences in content, rather than in cognitive processes within the ventral visual stream and medial temporal lobe.


Recognition, Psychology , Temporal Lobe , Animals , Humans , Brain , Cognition , Perception
10.
J Cogn Neurosci ; 35(5): 869-884, 2023 05 01.
Article En | MEDLINE | ID: mdl-36877081

The ability to flexibly categorize object concepts is essential to semantic cognition because the features that make two objects similar in one context may be irrelevant and even constitute interference in another. Thus, adaptive behavior in complex and dynamic environments requires the resolution of feature-based interference. In the current case study, we placed visual and functional semantic features in opposition across object concepts in two categorization tasks. Successful performance required the resolution of functional interference in a visual categorization task and the resolution of visual interference in a functional categorization task. In Experiment 1, we found that patient D. A., an individual with bilateral temporal lobe lesions, was unable to categorize object concepts in a context-dependent manner. His impairment was characterized by an increased tendency to incorrectly group objects that were similar on the task-irrelevant dimension, revealing an inability to resolve cross-modal semantic interference. In Experiment 2, D. A.'s categorization accuracy was comparable to controls when lures were removed, indicating that his impairment is unique to contexts that involve cross-modal interference. In Experiment 3, he again performed as well as controls when categorizing simple concepts, suggesting that his impairment is specific to categorization of complex object concepts. These results advance our understanding of the anterior temporal lobe as a system that represents object concepts in a manner that enables flexible semantic cognition. Specifically, they reveal a dissociation between semantic representations that contribute to the resolution of cross-modal interference and those that contribute to the resolution of interference within a given modality.


Semantics , Temporal Lobe , Male , Humans , Temporal Lobe/pathology , Cognition , Magnetic Resonance Imaging
11.
Nat Methods ; 20(4): 590-599, 2023 04.
Article En | MEDLINE | ID: mdl-36928074

Our understanding of nerve regeneration can be enhanced by delineating its underlying molecular activities at single-neuron resolution in model organisms such as Caenorhabditis elegans. Existing cell isolation techniques cannot isolate neurons with specific regeneration phenotypes from C. elegans. We present femtosecond laser microdissection (fs-LM), a single-cell isolation method that dissects specific cells directly from living tissue by leveraging the micrometer-scale precision of fs-laser ablation. We show that fs-LM facilitates sensitive and specific gene expression profiling by single-cell RNA sequencing (scRNA-seq), while mitigating the stress-related transcriptional artifacts induced by tissue dissociation. scRNA-seq of fs-LM isolated regenerating neurons revealed transcriptional programs that are correlated with either successful or failed regeneration in wild-type and dlk-1 (0) animals, respectively. This method also allowed studying heterogeneity displayed by the same type of neuron and found gene modules with expression patterns correlated with axon regrowth rate. Our results establish fs-LM as a spatially resolved single-cell isolation method for phenotype-to-genotype mapping.


Caenorhabditis elegans Proteins , Caenorhabditis elegans , Animals , Caenorhabditis elegans/genetics , Microdissection/methods , Neurons/physiology , Lasers , Sequence Analysis, RNA , MAP Kinase Kinase Kinases , Caenorhabditis elegans Proteins/genetics
12.
Mem Cognit ; 51(6): 1287-1302, 2023 08.
Article En | MEDLINE | ID: mdl-36995574

The accuracy of eyewitness interviews has legal and clinical implications within the criminal justice system. Leading verbal suggestions have been shown to give rise to false memories and inaccurate testimonies in children, but only a small body of research exists regarding non-verbal communication. The present study examined whether 5- to 8-year-olds in the UK could be misled about their memory of an event through exposure to leading gestural information, which suggested an incorrect response, using a variety of question and gesture types. Results showed that leading gestures significantly corrupted participants' memory compared to the control group (MD = 0.60, p < 0.001), with participants being misled by at least one question nearly three-quarters of the time. Questions about peripheral details, and gestures that were more visible and expressive, increased false memory further, with even subtle gestures demonstrating a strong misleading influence. We discuss the implications of these findings for the guidelines governing eyewitness interviews.


Gestures , Memory , Child , Humans
13.
Eur Urol ; 83(6): 534-547, 2023 06.
Article En | MEDLINE | ID: mdl-36964042

CONTEXT: Minimally invasive surgical therapies for male lower urinary tract symptoms secondary to benign prostatic obstruction were developed to be safer and more tolerable than standard ablative techniques. These treatments have not been compared with each other in a randomised fashion, and for some treatments, there are no trials against a reference technique. OBJECTIVE: To compare the efficacy, safety, and tolerability of water vapour thermal therapy (WVTT), prostatic urethral lift (PUL), prostatic arterial embolisation (PAE), temporary implantable nitinol device (iTIND), transurethral microwave thermotherapy (TUMT), and transurethral resection of the prostate (TURP). EVIDENCE ACQUISITION: A systematic search of MEDLINE/PubMed, Embase, Cochrane Library, and grey literature for randomised controlled trials was performed. Trials meeting the selection criteria were assessed for the risk of bias using the Cochrane RoB2 tool. Treatments were compared, using a network meta-analysis, in terms of outcomes including symptom score, quality of life, maximum urinary flow rate, postvoid residual urine, International Index of Erectile Function (IIEF-5), and scales from the Male Sexual Health Questionnaire. EVIDENCE SYNTHESIS: The search identified 63 trials. Symptoms and quality of life for PAE, PUL, and WVTT appeared similar to those for TURP, whereas TURP was found to have the most clinically significant improvement in flow rate. TUMT was less efficacious than TURP but provided similar results on quality of life. Comparisons of ejaculatory function favoured WVTT and PUL compared with TURP. The relative efficacy of iTIND was less clear because of the risk of bias in the respective trial. CONCLUSIONS: PAE, PUL, and WVTT appear favourable from a risk-benefit perspective despite probably having less efficacy than TURP for objective outcomes. These findings warrant confirmation through long-term randomised controlled trials. PATIENT SUMMARY: This paper has summarised the evidence from 63 clinical trials on minimally invasive surgical therapies for men with symptoms of an enlarged prostate, including water vapour thermal therapy (WVTT), prostatic urethral lift (PUL), prostatic arterial embolisation (PAE), temporary implantable nitinol device, and transurethral microwave thermotherapy (TUMT). Improvement in symptoms for each of PAE, PUL, TUMT, and WVTT in short-term follow-up was similar to that for the standard surgical treatment, although standard surgery appeared to provide the greatest increase in urine flow. Men who had WVTT or PUL were less likely to have problems with sexual function than those who had standard surgery.


Lower Urinary Tract Symptoms , Prostatic Hyperplasia , Transurethral Resection of Prostate , Humans , Male , Transurethral Resection of Prostate/adverse effects , Quality of Life , Network Meta-Analysis , Steam , Prostatic Hyperplasia/therapy , Prostatic Hyperplasia/surgery , Lower Urinary Tract Symptoms/therapy , Lower Urinary Tract Symptoms/surgery , Treatment Outcome
14.
EJHaem ; 4(1): 199-206, 2023 Feb.
Article En | MEDLINE | ID: mdl-36819156

Veno-occlusive disease/sinusoidal obstruction syndrome (VOD/SOS) is a rare, serious complication following haematopoietic cell transplantation (HCT). This systematic literature review evaluated differences in clinical manifestations of VOD/SOS post-HCT in adults and children. Medline and Embase were searched up to 4 March 2021 for reports of VOD/SOS post-HCT; VOD/SOS diagnostic guidelines were included. Publications were evaluated based on inclusion of five cardinal clinical features of VOD/SOS (ascites, hepatomegaly, hyperbilirubinaemia, right upper quadrant [RUQ] pain and weight gain ≥5%). Overall, 204 publications were included. At diagnosis, hyperbilirubinaemia was more common in adults (93%) versus children (82%), weight gain ≥5% and hepatomegaly were more common in children (86%, 89%) versus adults (73%, 76%) and ascites and RUQ pain were similar between age groups. While 40% of cases had all five cardinal features, age was not a substantial determinant of the likelihood of missing any single specific feature. The proportion of cases, where hyperbilirubinaemia was the first recorded feature, was higher in children versus adults; weight gain and RUQ pain appeared first in a greater proportion of adults versus children. VOD/SOS diagnosis can be challenging; features may not present in a distinct sequence. This necessitates continuous vigilance by those involved in patient monitoring post-HCT.

15.
Proc Natl Acad Sci U S A ; 119(51): e2214285119, 2022 12 20.
Article En | MEDLINE | ID: mdl-36512503

The act of remembering an everyday experience influences how we interpret the world, how we think about the future, and how we perceive ourselves. It also enhances long-term retention of the recalled content, increasing the likelihood that it will be recalled again. Unfortunately, the ability to recollect event-specific details and reexperience the past tends to decline with age. This decline in recollection may reflect a corresponding decrease in the distinctiveness of hippocampal memory representations. Despite these well-established changes, there are few effective cognitive behavioral interventions that target real-world episodic memory. We addressed this gap by developing a smartphone-based application called HippoCamera that allows participants to record labeled videos of everyday events and subsequently replay, high-fidelity autobiographical memory cues. In two experiments, we found that older adults were able to easily integrate this noninvasive intervention into their daily lives. Using HippoCamera to repeatedly reactivate memories for real-world events improved episodic recollection and it evoked more positive autobiographical sentiment at the time of retrieval. In both experiments, these benefits were observed shortly after the intervention and again after a 3-mo delay. Moreover, more detailed recollection was associated with more differentiated memory signals in the hippocampus. Thus, using this smartphone application to systematically reactivate memories for recent real-world experiences can help to maintain a bridge between the present and past in older adults.


Memory, Episodic , Smartphone , Humans , Aged , Mental Recall/physiology , Hippocampus/physiology , Cues
16.
Ecol Lett ; 25(12): 2637-2650, 2022 Dec.
Article En | MEDLINE | ID: mdl-36257904

Considering the global intensification of aridity in tropical biomes due to climate change, we need to understand what shapes the distribution of drought sensitivity in tropical plants. We conducted a pantropical data synthesis representing 1117 species to test whether xylem-specific hydraulic conductivity (KS ), water potential at leaf turgor loss (ΨTLP ) and water potential at 50% loss of KS (ΨP50 ) varied along climate gradients. The ΨTLP and ΨP50 increased with climatic moisture only for evergreen species, but KS did not. Species with high ΨTLP and ΨP50 values were associated with both dry and wet environments. However, drought-deciduous species showed high ΨTLP and ΨP50 values regardless of water availability, whereas evergreen species only in wet environments. All three traits showed a weak phylogenetic signal and a short half-life. These results suggest strong environmental controls on trait variance, which in turn is modulated by leaf habit along climatic moisture gradients in the tropics.


Droughts , Plant Leaves , Tropical Climate , Phylogeny , Plant Leaves/physiology , Xylem
17.
Nat Commun ; 13(1): 3332, 2022 06 09.
Article En | MEDLINE | ID: mdl-35680917

Lianas, or woody vines, and trees dominate the canopy of tropical forests and comprise the majority of tropical aboveground carbon storage. These growth forms respond differently to contemporary variation in climate and resource availability, but their responses to future climate change are poorly understood because there are very few predictive ecosystem models representing lianas. We compile a database of liana functional traits (846 species) and use it to parameterize a mechanistic model of liana-tree competition. The substantial difference between liana and tree hydraulic conductivity represents a critical source of inter-growth form variation. Here, we show that lianas are many times more sensitive to drying atmospheric conditions than trees as a result of this trait difference. Further, we use our competition model and projections of tropical hydroclimate based on Representative Concentration Pathway 4.5 to show that lianas are more susceptible to reaching a hydraulic threshold for viability by 2100.


Ecosystem , Tropical Climate , Forests , Plants , Trees
18.
Oxf Bull Econ Stat ; 2022 Apr 18.
Article En | MEDLINE | ID: mdl-35601477

This article studies the impact of the Covid-19 pandemic on graduates and non-graduates in the United Kingdom. We construct a DSGE model with search frictions that is designed around key features of the UK labour market and simulate the model using an array of shocks, designed to mimic the impact of the Covid-19 pandemic. We show that our relatively simple macroeconomic model can describe the impact of the pandemic on output, employment and wages. Our results show that the impact of the pandemic on employment and wages was more severe for non-graduates than for graduates, and that up to 5 million jobs would have been lost in the first wave of the pandemic in the absence of the Job Retention Scheme.

19.
New Phytol ; 235(3): 1005-1017, 2022 08.
Article En | MEDLINE | ID: mdl-35608089

Rapid changes in climate and disturbance regimes, including droughts and hurricanes, are likely to influence tropical forests, but our understanding of the compound effects of disturbances on forest ecosystems is extremely limited. Filling this knowledge gap is necessary to elucidate the future of these ecosystems under a changing climate. We examined the relationship between hurricane response (damage, mortality, and resilience) and four hydraulic traits of 13 dominant woody species in a wet tropical forest subject to periodic hurricanes. Species with high resistance to embolisms (low P50 values) and higher safety margins ( SMP50 ) were more resistant to immediate hurricane mortality and breakage, whereas species with higher hurricane resilience (rapid post-hurricane growth) had high capacitance and P50 values and low SMP50 . During 26 yr of post-hurricane recovery, we found a decrease in community-weighted mean values for traits associated with greater drought resistance (leaf turgor loss point, P50 , SMP50 ) and an increase in capacitance, which has been linked with lower drought resistance. Hurricane damage favors slow-growing, drought-tolerant species, whereas post-hurricane high resource conditions favor acquisitive, fast-growing but drought-vulnerable species, increasing forest productivity at the expense of drought tolerance and leading to higher overall forest vulnerability to drought.


Cyclonic Storms , Droughts , Ecosystem , Forests , Plant Leaves/physiology , Trees/physiology , Tropical Climate , Water/physiology
20.
Elife ; 112022 03 21.
Article En | MEDLINE | ID: mdl-35311645

Vision neuroscience has made great strides in understanding the hierarchical organization of object representations along the ventral visual stream (VVS). How VVS representations capture fine-grained visual similarities between objects that observers subjectively perceive has received limited examination so far. In the current study, we addressed this question by focussing on perceived visual similarities among subordinate exemplars of real-world categories. We hypothesized that these perceived similarities are reflected with highest fidelity in neural activity patterns downstream from inferotemporal regions, namely in perirhinal (PrC) and anterolateral entorhinal cortex (alErC) in the medial temporal lobe. To address this issue with functional magnetic resonance imaging (fMRI), we administered a modified 1-back task that required discrimination between category exemplars as well as categorization. Further, we obtained observer-specific ratings of perceived visual similarities, which predicted behavioural discrimination performance during scanning. As anticipated, we found that activity patterns in PrC and alErC predicted the structure of perceived visual similarity relationships among category exemplars, including its observer-specific component, with higher precision than any other VVS region. Our findings provide new evidence that subjective aspects of object perception that rely on fine-grained visual differentiation are reflected with highest fidelity in the medial temporal lobe.


Entorhinal Cortex , Temporal Lobe , Brain Mapping , Entorhinal Cortex/pathology , Magnetic Resonance Imaging , Pattern Recognition, Visual , Photic Stimulation
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