Are age-related changes in perceptual-motor regulation related to an increased falls risk?

Introduction Decades of research have shown that approximately one in three older adults, aged 65 years or older, falls at least once each year (Campbell et al., 1990; World Health Organization, 2007). This is a problem in our ageing society; as the number of people in this aged cohort continues to increase, leading to an expected increase of falls and falls related medical costs in the coming years (Hendrie, Hall, Arena, & Legge, 2004). The consequences of falling are not only severe in terms of medical costs, for older adults a fall means injuries, decreases in quality of life and could even lead to death (Burns, Stevens, & Lee, 2016). The current thesis adopts an ecological approach to investigate opportunities for falls prevention. According to an ecological approach, guidance of action is mediated by the perception of ‘opportunities for action’ or ‘affordances’ (Gibson, 1979). These affordances are always action scaled; a person perceives possibilities for action in relation to his or her own action system. For instance, a curb might afford ‘stepping onto’ for me, as I have sufficient leg length and strength to perform a step up, however, it will afford ‘climbing onto’ for a toddler who’s legs might not yet have the length to afford stepping onto the curb. Perception of affordances is therefore influenced by how well a person knows his or her own capabilities or in other words how well one ‘calibrates’ perception and action. To achieve this calibration, one needs to experience of ‘explore’ one’s action system, or, as Gibson (1979) put it: "…we must perceive in order to move, but we must also move in order to perceive" (p. 213). This cyclic nature of perception forms the basis for the perception and action cycle and perceptual-motor coupling. The perception and action cycle can help to understand successful movement and therefore potentially to explain movement errors (such as the ones leading to falls) as well. If one component of the perception and action cycle is unsuccessful it could affect success in movement. For instance, if a person would not calibrate properly, making one insecure about one’s own action capabilities, it might lead to insecurities in moving around. From this it follows that for successful performance, it is important to successfully couple perception and action. Aims, Methods and Results per Study The current study incorporates four inter-related studies with differing methods. The first study (described in Chapter 2) is a systematic review, which sought to investigate the perceptual-motor calibration component of the perception and action cycle. The aim of this study was to assess in what conditions calibration occurs most efficiently, with a sub-aim to assess what is known about age-related changes in calibration. Seven databases were screened to identify literature that combined topics related to ‘perception’, ‘action’ and ‘calibration’ or ‘scaling’. Twenty-three papers satisfied the inclusion criteria. Results of the first study showed that calibration occurs rapidly if the movements performed to explore the perceptual and action coupling provide relevant information for perception. For instance, when standing height is raised by placing a participant on 10-cm high blocks, calibration occurred rapidly when participants were allowed to walk with the block (allowing much exploration), but not when only allowed standing stationary with no body movement (Mark, Balliett, Craver, Douglas, & Fox, 1990). Furthermore, this study identified a general limitation in the research on calibration; no studies have been identified that have studied calibration to changed action capabilities in an older cohort. The second, third and fourth study in this thesis (described in Chapter 4, Chapter 5 and Chapter 6) all use the same ‘curb-approach task’ to study the regulation of gait towards a target. For each trial in the curb approach task, participants were positioned at the far end of an 8m long GAITRite pressure sensitive walkway (GAITRite®, CIR Systems, Inc., Franklyn, NJ, USA). At a ‘go’ signal, participants started walking the length of the walkway (placing one footfall on a target that was randomly placed in the first 3 meters of the walk to prevent participants from performing identical walks in each trial), to the end of the walkway where a curb-like platform (L: 2m, W: 1m, H: 0.15m) was positioned. Participants stepped onto the platform and continued to the far end at which a push-button was positioned that signaled the end of the trial. 33 trials were performed per participant. Outcome measures of the curb-approach task were related to three analyses introduced in previous studies in locomotor pointing (De Rugy, Taga, et al., 2002; Montagne et al., 2000). Firstly, an analysis was introduced that assessed the changes in variability (standard deviation) of the position of foot placements. Secondly, an analysis was introduced that assessed whether the timing of the initiation of adaptations in gait (deviations from a ‘standard’ step) are related to the total amount of adjustments to be made (indicating a perception-action coupling). Finally, an analysis was introduced VII that assessed the strength of perceptual-motor coupling; the degree to which changes in step length depended on the perception of required adjustments. The second study (as described in Chapter 4) aimed to assess whether successful performance in the curb-approach task required similar perceptual-motor regulation compared to the long-jump run up. Sixteen younger adults were included and ask to perform the curb-approach task. Results confirmed the similarities between the curb-approach and the long jump approach. Regulation seemed to be initiated earlier in the curb-approach compared to the long jump, but a similar pattern was observed in decreasing variability of foot placement and an increasingly stronger perceptual-motor coupling as participants got closer to their target in both tasks. The second study concluded that the curb-approach task would provide an effective paradigm to study perceptual-motor regulation in an older cohort (for whom a long jump would be too demanding). The third study (Chapter 5) aimed to assess age-related changes in regulation in the curb approach task. In this study, the data collected from the 16 younger participants (study2) was compared to data collected from a cohort of 105 older adults. Results showed that with older age, participants showed less variability in foot placement during their approach. Furthermore, it was shown that with age, participants were more likely to adopt a strategy that involved shortening rather than lengthening of steps. Age-related changes were most prominent in the measures of strength of perceptual-motor regulation. Similar to the younger participants, older participants showed an increased strength of coupling (or in other words; made stronger adjustments) as they got closer to the curb. However, it was also shown that with age the strength of the coupling over all steps increased, indicating that the older participants made stronger gait adaptations. As the third study identified that age-related changes are most prominent in the measures of perceptual-motor coupling, it was decided to focus the final study (Chapter 6) on the question whether these changes could be related to an increased risk of falls. Ninety-eight participants were included in the analysis for this study, who first performed the curb-approach task and then were entered in a 12 –month follow-up to screen for the occurrence of gait-related falls. Results showed that participants who reported experiencing a gait-related fall showed stronger perceptual-motor coupling (stronger gait adaptations) in stepping onto the curb. Discussion and Conclusion The results of this thesis showed that the curb-approach task provides a novel and valid method to measure perceptual-motor regulation of locomotor pointing in in a low demands setting, suitable for the older cohort. Older adults showed stronger gait adaptations compared to their younger counterparts and adaptations in the step onto the curb were stronger still in on older adults prone to experiencing gait-related falls. These results suggest that, in controlling gait, humans are capable of changing the strength of perceptual-motor coupling in accordance with the difficulty of the task. With age, action capabilities decrease and the curb-approach task becomes harder; our results show that this is met with a strengthening of perceptual-motor coupling. Implications of the current thesis are that in falls risk screenings as well as falls prevention, it is important to consider the entire perception and action cycle. An ecologically-grounded functional approach to healthy aging is advocated which considers a person in relation to his/her behavior and environment (Vaz, Silva, Mancini, Carello, & Kinsella-Shaw, 2017)

A systematic review on perceptual-motor calibration to changes in action capabilities

Perceptual-motor calibration has been described as a mapping between perception and action, which is relevant to distinguish possible from impossible opportunities for action. To avoid movement errors, it is relevant to rapidly calibrate to immediate changes in capabilities and therefore this study sought to explain in what conditions calibration is most efficient. A systematic search of seven databases was conducted to identify literature concerning changes in calibration in response to changes in action capabilities. Twenty-three papers satisfied the inclusion criteria. Data revealed that calibration occurs rapidly if there is a good match between the task that requires calibration and the sources of perceptual-motor information available for exploration (e.g. when exploring maximal braking capabilities by experiencing braking). Calibration can take more time when the perceptual-motor information that is available is less relevant. The current study identified a number of limitations in the field of perceptual-motor research. Most notably, the mean participant age in the included studies was between 18 and 33 years of age, limiting the generalizability of the results to other age groups. Also, due to inconsistent terminology used in the field of perceptual-motor research, we argue that investigating calibration in older cohorts should be a focus of future research because of the possible implications of impaired calibration in an aging society

Associations between gait-related falls and gait adaptations when stepping onto a curb: A prospective falls study

Objectives. Examine gait regulation during the approach to stepping onto a curb for older adults who did or did not report gait-related falls over a 12-month follow-up. Methods. Ninety-eight participants aged 60 years and older were analyzed. Primary outcomes were step length adaptations (lengthening or shortening) during a curb approach and the occurrence of a gait-related fall during a 12-month follow-up. Results. Linear-mixed effects modelling indicated stronger adaptations towards the end of the approach. Participants who reported experiencing a gait-related fall showed a stronger relationship between the adjustment required and adjustment produced; indicating different gait adaptations during the step leading onto the curb. Discussion. The link between prospective gait-related falls and gait-adaptations indicated that older adults with reduced capabilities require stronger adaptations to complete tasks reminiscent of everyday life. This finding may provide insight into the mechanisms of falls in older adults and should inform new falls prevention interventions

Perceptual-motor regulation in locomotor pointing while approaching a curb

Locomotor pointing is a task that has been the focus of research in the context of sport (e.g. long jumping and cricket) as well as normal walking. Collectively, these studies have produced abroad understanding of locomotor pointing, but generalizability has been limited to laboratory type tasks and/or tasks with high spatial demands. The current study aimed to generalize previous findings in locomotor pointing to the common daily task of approaching and stepping on to a curb. Sixteen people completed 33 repetitions of a task that required them to walk up to and step onto a curb. Information about their foot placement was collected using a combination of measures derived from a pressure-sensitive walkway and video data. Variables related to perceptual-motor regulation were analyzed on an inter-trial, intra-step and inter-step level. Similar to previous studies, analysis of the foot placements showed that, variability in foot placement decreased as the participants drew closer to the curb. Regulation seemed to be initiated earlier in this study compared to previous studies, as shown by a decreasing variability in foot placement as early as eight steps before reaching the curb. Furthermore, it was shown that when walking up to the curb, most people regulated their walk in a way so as to achieve minimal variability in the foot placement on top of the curb, rather than a placement in front of the curb. Combined, these results showed a strong perceptual-motor coupling in the task of approaching and stepping up a curb, rendering this task a suitable test for perceptual-motor regulation in walking

Principles of the guidance of exploration for orientation and specification of action

To control movement of any type, the neural system requires perceptual information to distinguish what actions are possible in any given environment. The behavior aimed at collecting this information, termed “exploration”, is vital for successful movement control. Currently, the main function of exploration is understood in the context of specifying the requirements of the task at hand. To accommodate for agency and action-selection, we propose that this understanding needs to be supplemented with a function of exploration that logically precedes the specification of action requirements with the purpose of discovery of possibilities for action—action orientation. This study aimed to provide evidence for the delineation of exploration for action orientation and exploration for action specification using the principles from “General Tau Theory.” Sixteen male participants volunteered and performed a laboratory-based exploration task. The visual scenes of different task-specific situations were projected on five monitors surrounding the participant. At a predetermined time, the participant received a simulated ball and was asked to respond by indicating where they would next play the ball. Head movements were recorded using inertial sensors as a measure of exploratory activity. It was shown that movement guidance characteristics varied between different head turns as participants moved from exploration for orientation to exploration for action specification. The first head turn in the trial, used for action-orientation, showed later peaks in the velocity profile and harder closure of the movement gap (gap between the start and end of the head-movement) in comparison to the later head turns. However, no differences were found between the first and the final head turn, which we hypothesized are used mainly for action orientation and specification respectively. These results are in support of differences in the function and control of head movement for discovery of opportunities for action (orientation) vs. head movement for specification of task requirements. Both are important for natural movement, yet in experimental settings,orientation is often neglected. Including both orientation and action specification in an experimental design should maximize generalizability of an experiment to natural behavior. Future studies are required to study the neural bases of movement guidance in order to better understand exploration in anticipation of movement

When a fly ball is out of reach: catchability judgments are not based on optical acceleration cancelation.

The optical acceleration cancelation (OAC) strategy, based on Chapman’s (1968) analysis of the outfielder problem, has been the dominant account for the control of running to intercept fly balls approaching head on. According to the OAC strategy, outfielders will arrive at the interception location just in time to catch the ball when they keep optical acceleration zero. However, the affordance aspect of this task, that is, whether or not an approaching fly ball is catchable, is not part of this account. The present contribution examines whether the scope of the OAC strategy can be extended to also include the affordance aspect of running to catch a fly ball. This is done by considering a fielder’s action boundaries (i.e., maximum running velocity and – acceleration) in the context of the OAC strategy. From this, only when running velocity is maximal and optical acceleration is non-zero, a fielder would use OAC to perceive a fly ball as uncatchable. The present contribution puts this hypothesis to the test. Participants were required to try to intercept fly balls projected along their sagittal plane. Some fly balls were catchable whereas others were not. Participants were required to catch as many fly balls as possible and to call ‘no’ when they perceived a fly ball to be uncatchable. Participants’ running velocity and –acceleration at the moment of calling ‘no’ were examined. Results showed that participants’ running velocity was submaximal before or while calling ‘no’. Also running acceleration was often submaximal. These results cannot be explained by the use of OAC in judging catchability and ultimately call for a new strategy of locomotor control in running to catch a fly ball

Transcriptional Silencing of the Wnt-Antagonist DKK1 by Promoter Methylation Is Associated with Enhanced Wnt Signaling in Advanced Multiple Myeloma

The Wnt/β-catenin pathway plays a crucial role in the pathogenesis of various human cancers. In multiple myeloma (MM), aberrant auto-and/or paracrine activation of canonical Wnt signaling promotes proliferation and dissemination, while overexpression of the Wnt inhibitor Dickkopf1 (DKK1) by MM cells contributes to osteolytic bone disease by inhibiting osteoblast differentiation. Since DKK1 itself is a target of TCF/β-catenin mediated transcription, these findings suggest that DKK1 is part of a negative feedback loop in MM and may act as a tumor suppressor. In line with this hypothesis, we show here that DKK1 expression is low or undetectable in a subset of patients with advanced MM as well as in MM cell lines. This absence of DKK1 is correlated with enhanced Wnt pathway activation, evidenced by nuclear accumulation of β-catenin, which in turn can be antagonized by restoring DKK1 expression. Analysis of the DKK1 promoter revealed CpG island methylation in several MM cell lines as well as in MM cells from patients with advanced MM. Moreover, demethylation of the DKK1 promoter restores DKK1 expression, which results in inhibition of β-catenin/TCF-mediated gene transcription in MM lines. Taken together, our data identify aberrant methylation of the DKK1 promoter as a cause of DKK1 silencing in advanced stage MM, which may play an important role in the progression of MM by unleashing Wnt signaling

Taking the pulse of Earth's tropical forests using networks of highly distributed plots

Tropical forests are the most diverse and productive ecosystems on Earth. While better understanding of these forests is critical for our collective future, until quite recently efforts to measure and monitor them have been largely disconnected. Networking is essential to discover the answers to questions that transcend borders and the horizons of funding agencies. Here we show how a global community is responding to the challenges of tropical ecosystem research with diverse teams measuring forests tree-by-tree in thousands of long-term plots. We review the major scientific discoveries of this work and show how this process is changing tropical forest science. Our core approach involves linking long-term grassroots initiatives with standardized protocols and data management to generate robust scaled-up results. By connecting tropical researchers and elevating their status, our Social Research Network model recognises the key role of the data originator in scientific discovery. Conceived in 1999 with RAINFOR (South America), our permanent plot networks have been adapted to Africa (AfriTRON) and Southeast Asia (T-FORCES) and widely emulated worldwide. Now these multiple initiatives are integrated via ForestPlots.net cyber-infrastructure, linking colleagues from 54 countries across 24 plot networks. Collectively these are transforming understanding of tropical forests and their biospheric role. Together we have discovered how, where and why forest carbon and biodiversity are responding to climate change, and how they feedback on it. This long-term pan-tropical collaboration has revealed a large long-term carbon sink and its trends, as well as making clear which drivers are most important, which forest processes are affected, where they are changing, what the lags are, and the likely future responses of tropical forests as the climate continues to change. By leveraging a remarkably old technology, plot networks are sparking a very modern revolution in tropical forest science. In the future, humanity can benefit greatly by nurturing the grassroots communities now collectively capable of generating unique, long-term understanding of Earth's most precious forests. Resumen Los bosques tropicales son los ecosistemas más diversos y productivos del mundo y entender su funcionamiento es crítico para nuestro futuro colectivo. Sin embargo, hasta hace muy poco, los esfuerzos para medirlos y monitorearlos han estado muy desconectados. El trabajo en redes es esencial para descubrir las respuestas a preguntas que trascienden las fronteras y los plazos de las agencias de financiamiento. Aquí mostramos cómo una comunidad global está respondiendo a los desafíos de la investigación en ecosistemas tropicales a través de diversos equipos realizando mediciones árbol por árbol en miles de parcelas permanentes de largo plazo. Revisamos los descubrimientos más importantes de este trabajo y discutimos cómo este proceso está cambiando la ciencia relacionada a los bosques tropicales. El enfoque central de nuestro esfuerzo implica la conexión de iniciativas locales de largo plazo con protocolos estandarizados y manejo de datos para producir resultados que se puedan trasladar a múltiples escalas. Conectando investigadores tropicales, elevando su posición y estatus, nuestro modelo de Red Social de Investigación reconoce el rol fundamental que tienen, para el descubrimiento científico, quienes generan o producen los datos. Concebida en 1999 con RAINFOR (Suramérica), nuestras redes de parcelas permanentes han sido adaptadas en África (AfriTRON) y el sureste asiático (T-FORCES) y ampliamente replicadas en el mundo. Actualmente todas estas iniciativas están integradas a través de la ciber-infraestructura de ForestPlots.net, conectando colegas de 54 países en 24 redes diferentes de parcelas. Colectivamente, estas redes están transformando nuestro conocimiento sobre los bosques tropicales y el rol de éstos en la biósfera. Juntos hemos descubierto cómo, dónde y porqué el carbono y la biodiversidad de los bosques tropicales está respondiendo al cambio climático y cómo se retroalimentan. Esta colaboración pan-tropical de largo plazo ha expuesto un gran sumidero de carbono y sus tendencias, mostrando claramente cuáles son los factores más importantes, qué procesos se ven afectados, dónde ocurren los cambios, los tiempos de reacción y las probables respuestas futuras mientras el clima continúa cambiando. Apalancando lo que realmente es una tecnología antigua, las redes de parcelas están generando una verdadera y moderna revolución en la ciencia tropical. En el futuro, la humanidad puede beneficiarse enormemente si se nutren y cultivan comunidades de investigadores de base, actualmente con la capacidad de generar información única y de largo plazo para entender los que probablemente son los bosques más preciados de la tierra. Resumo Florestas tropicais são os ecossistemas mais diversos e produtivos da Terra. Embora uma boa compreensão destas florestas seja crucial para o nosso futuro coletivo, até muito recentemente os esforços de medições e monitoramento foram amplamente desconexos. É essencial formarmos redes para obtermos respostas que transcendem fronteiras e horizontes de agências financiadoras. Neste estudo nós mostramos como uma comunidade global está respondendo aos desafios da pesquisa de ecossistemas tropicais, com equipes diversas medindo florestas, árvore por árvore, em milhares de parcelas monitoradas à longo prazo. Nós revisamos as maiores descobertas científicas deste trabalho, e mostramos também como este processo está mudando a ciência de florestas tropicais. Nossa abordagem principal envolve unir iniciativas de base a protocolos padronizados e gerenciamento de dados a fim de gerar resultados robustos em escalas ampliadas. Ao conectar pesquisadores tropicais e elevar seus status, nosso modelo de Rede de Pesquisa Social reconhece o papel-chave do produtor dos dados na descoberta científica. Concebida em 1999 com o RAINFOR (América do Sul), nossa rede de parcelas permanentes foi adaptada para África (AfriTRON) e Sudeste asiático (T-FORCES), e tem sido extensamente reproduzida em todo o mundo. Agora estas múltiplas iniciativas estão integradas através de uma infraestrutura cibernética do ForestPlots.net, conectando colegas de 54 países de 24 redes de parcelas. Estas iniciativas estão transformando coletivamente o entendimento das florestas tropicais e seus papéis na biosfera. Juntos nós descobrimos como, onde e por que o carbono e a biodiversidade da floresta estão respondendo às mudanças climáticas, e seus efeitos de retroalimentação. Esta duradoura colaboração pantropical revelou um grande sumidouro de carbono persistente e suas tendências, assim como tem evidenciado quais direcionadores são mais importantes, quais processos florestais são mais afetados, onde eles estão mudando, seus atrasos no tempo de resposta, e as prováveis respostas das florestas tropicais conforme o clima continua a mudar. Dessa forma, aproveitando uma notável tecnologia antiga, redes de parcelas acendem faíscas de uma moderna revolução na ciência das florestas tropicais. No futuro a humanidade pode se beneficiar incentivando estas comunidades basais que agora são coletivamente capazes de gerar conhecimentos únicos e duradouros sobre as florestas mais preciosas da Terra. Résume Les forêts tropicales sont les écosystèmes les plus diversifiés et les plus productifs de la planète. Si une meilleure compréhension de ces forêts est essentielle pour notre avenir collectif, jusqu'à tout récemment, les efforts déployés pour les mesurer et les surveiller ont été largement déconnectés. La mise en réseau est essentielle pour découvrir les réponses à des questions qui dépassent les frontières et les horizons des organismes de financement. Nous montrons ici comment une communauté mondiale relève les défis de la recherche sur les écosystèmes tropicaux avec diverses équipes qui mesurent les forêts arbre après arbre dans de milliers de parcelles permanentes. Nous passons en revue les principales découvertes scientifiques de ces travaux et montrons comment ce processus modifie la science des forêts tropicales. Notre approche principale consiste à relier les initiatives de base à long terme à des protocoles standardisés et une gestion de données afin de générer des résultats solides à grande échelle. En reliant les chercheurs tropicaux et en élevant leur statut, notre modèle de réseau de recherche sociale reconnaît le rôle clé de l'auteur des données dans la découverte scientifique. Conçus en 1999 avec RAINFOR (Amérique du Sud), nos réseaux de parcelles permanentes ont été adaptés à l'Afrique (AfriTRON) et à l'Asie du Sud-Est (T-FORCES) et largement imités dans le monde entier. Ces multiples initiatives sont désormais intégrées via l'infrastructure ForestPlots.net, qui relie des collègues de 54 pays à travers 24 réseaux de parcelles. Ensemble, elles transforment la compréhension des forêts tropicales et de leur rôle biosphérique. Ensemble, nous avons découvert comment, où et pourquoi le carbone forestier et la biodiversité réagissent au changement climatique, et comment ils y réagissent. Cette collaboration pan-tropicale à long terme a révélé un important puits de carbone à long terme et ses tendances, tout en mettant en évidence les facteurs les plus importants, les processus forestiers qui sont affectés, les endroits où ils changent, les décalages et les réactions futures probables des forêts tropicales à mesure que le climat continue de changer. En tirant parti d'une technologie remarquablement ancienne, les réseaux de parcelles déclenchent une révolution très moderne dans la science des forêts tropicales. À l'avenir, l'humanité pourra grandement bénéficier du soutien des communautés de base qui sont maintenant collectivement capables de générer une compréhension unique et à long terme des forêts les plus précieuses de la Terre. Abstrak Hutan tropika adalah di antara ekosistem yang paling produktif dan mempunyai kepelbagaian biodiversiti yang tinggi di seluruh dunia. Walaupun pemahaman mengenai hutan tropika amat penting untuk masa depan kita, usaha-usaha untuk mengkaji dan mengawas hutah-hutan tersebut baru sekarang menjadi lebih diperhubungkan. Perangkaian adalah sangat penting untuk mencari jawapan kepada soalan-soalan yang menjangkaui sempadan dan batasan agensi pendanaan. Di sini kami menunjukkan bagaimana sebuah komuniti global bertindak balas terhadap cabaran penyelidikan ekosistem tropika melalui penglibatan pelbagai kumpulan yang mengukur hutan secara pokok demi pokok dalam beribu-ribu plot jangka panjang. Kami meninjau semula penemuan saintifik utama daripada kerja ini dan menunjukkan bagaimana proses ini sedang mengubah bidang sains hutan tropika. Teras pendekatan kami memberi tumpuan terhadap penghubungan inisiatif akar umbi jangka panjang dengan protokol standar serta pengurusan data untuk mendapatkan hasil skala besar yang kukuh. Dengan menghubungkan penyelidik-penyelidik tropika dan meningkatkan status mereka, model Rangkaian Penyelidikan Sosial kami mengiktiraf kepentingan peranan pengasas data dalam penemuan saintifik. Bermula dengan pengasasan RAINFOR (Amerika Selatan) pada tahun 1999, rangkaian-rangkaian plot kekal kami kemudian disesuaikan untuk Afrika (AfriTRON) dan Asia Tenggara (T-FORCES) dan selanjutnya telah banyak dicontohi di seluruh dunia. Kini, inisiatif-inisiatif tersebut disepadukan melalui infrastruktur siber ForestPlots.net yang menghubungkan rakan sekerja dari 54 negara di 24 buah rangkaian plot. Secara kolektif, rangkaian ini sedang mengubah pemahaman tentang hutan tropika dan peranannya dalam biosfera. Kami telah bekerjasama untuk menemukan bagaimana, di mana dan mengapa karbon serta biodiversiti hutan bertindak balas terhadap perubahan iklim dan juga bagaimana mereka saling bermaklum balas. Kolaborasi pan-tropika jangka panjang ini telah mendedahkan sebuah sinki karbon jangka panjang serta arah alirannya dan juga menjelaskan pemandu-pemandu perubahan yang terpenting, di mana dan bagaimana proses hutan terjejas, masa susul yang ada dan kemungkinan tindakbalas hutan tropika pada perubahan iklim secara berterusan di masa depan. Dengan memanfaatkan pendekatan lama, rangkaian plot sedang menyalakan revolusi yang amat moden dalam sains hutan tropika. Pada masa akan datang, manusia sejagat akan banyak mendapat manfaat jika memupuk komuniti-komuniti akar umbi yang kini berkemampuan secara kolektif menghasilkan pemahaman unik dan jangka panjang mengenai hutan-hutan yang paling berharga di dunia