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Explicit (declarative) memory declines with age, but age effects on implicit (nondeclarative) memory are debated. Some studies have reported null changes in implicit memory (e.g., priming in word-fragment completion, perceptual identification, category exemplar generation) with age, while others have uncovered declines. One factor that may account for these discrepancies is processing. Evidence suggests that conceptual and perceptual processes are not equally affected by ageing, yet processing requirements have varied greatly between studies. Processing may moderate age effects on priming, but no study has systematically examined this issue. This registered report presents an experiment to manipulate processing (conceptual / perceptual) during incidental encoding of words, prior to measures of perceptual (perceptual identification) and conceptual (category verification) priming. The perceptual and conceptual priming tasks were matched on all characteristics except processing, making them highly comparable. The four orthogonal conditions (perceptual encoding, perceptual test [PP]; conceptual encoding, perceptual test [CP]; perceptual encoding, conceptual test [PC]; conceptual encoding, conceptual test [CC]) were designed to clarify situations in which age effects on implicit memory emerge, which holds important practical and theoretical implications. Significant effects of Age, Test, and an Age × Processing interaction emerged. Priming was greater in young than older adults and on the perceptual than the conceptual test, but in contrast to the predictions, the age difference was only significant when prior encoding was perceptual (i.e., in the PP and CP conditions).

Halophila stipulacea, a small seagrass species native to the Indo-Pacific, is a Lessepsian migrant and a high-profile invader that has successfully colonized two exotic regions, the Mediterranean (first observed in 1894) and the Caribbean (2002). In 1961, an intracellular phytomyxid parasite, Marinomyxa marina (SAR: Rhizaria: Endomyxa: Phytomyxea) was discovered in the petioles of H. stipulacea in the Red Sea, and three decades later, it was reported off the coast of Sicily (Mediterranean), suggesting parallel migration of the two organisms. In 2018, infected petioles of H. stipulacea were also observed in St. Eustatius (Caribbean), but the identity of the causative agent remained unresolved. Here, we provide information on four new localities of phytomyxid-infested populations of H. stipulacea in Greece (Mediterranean), and Bonaire and Martinique (Caribbean), including notes on infection prevalence and seasonal dynamics. Using the 18S rRNA barcoding gene, we bring molecular evidence that the disease is caused by a genetically uniform variant of M. marina at all the examined sites. We conclude that the parasite is now widespread throughout both invaded regions and has been present in the Caribbean since 2013 at the latest. For the first time, the production of fruits in infected plants is observed, indicating a non-lethal nature of the symbiosis. While the arrival of M. marina to the Caribbean is unlikely to alleviate the current invasiveness of H. stipulacea, we emphasize the need for its further monitoring since the host-specificity and general biology of seagrass-associated phytomyxids are still poorly understood.

Contains fulltext : 235019.pdf (Publisher’s version ) (Open Access) Predictive Processing accounts of autism claim that autistic individuals assign higher precision to their prediction errors than non-autistic individuals, that is, autistic individuals update their predictions more readily when faced with unexpected sensory input. Since setting the level of precision is a fundamental part of perception and learning, we propose that such differences should be detectable in various domains at a very early age, before clinical symptoms have fully emerged. We therefore tested 3-year-old younger siblings of autistic children, with a high likelihood of later receiving an autism diagnosis themselves, and low-likelihood children with an older sibling without autism. We used a novel implicit learning paradigm to examine the effect of sensory noise on the predictions participants built. In order to learn a sequence, our participants had to select which visual information to attend to and disregard low-level prediction errors caused by the sensory noise, which the theory claims is more difficult for autistic individuals. Contrary to the proposed higher precision-weighting of prediction errors in autism, the high-likelihood children did not show signs of updating their predictions more readily when we added sensory noise compared to the low-likelihood children, either in their reaction times or in the recurrence and determinism of their response locations. These results raise challenges for Predictive Processing theories of autism, specifically for the notion that prediction errors are inflexibly highly weighted by individuals with autism. 11 p.

Predictive Processing accounts of autism posit that autistic individuals’ perception is less biased by expectations than non-autistic individuals’, perhaps through stronger precision-weighting of prediction errors. Since precision-weighting is fundamental to all information processing, any differences between autistic and non-autistic individuals should be domain-general and observable in both behaviour and brain responses. This study tested these theoretical predictions in gaze-direction adaptation, using EEG, behavioural responses and eye-tracking co-registration to investigate whether increased precision-weighting of prediction errors is evident through smaller adaptation after-effects in autistic adolescents compared to non-autistic peers. Multi-level modelling showed that autistic and non-autistic adolescents’ responses were consistent with behavioural adaptation, with Bayesian statistics providing extremely strong evidence for the absence of a group difference. Cluster-based permutation testing of ERP responses did not show the expected larger reduction in the N170 or P2 components in response to adapted compared to unadapted stimuli, and no group difference was detected. Combined with the few other available studies, the current findings raise challenges for the theory, suggesting no fundamental difference in precision-weighting of prediction errors in autism.

Item does not contain fulltext Building object representations is crucial for understanding the visual world, but it is not yet understood how infants start to form these representations. In adults, theta power is higher during presentation of stimuli that were later remembered, compared to those later forgotten (Friese et al., 2013), and the coupling between theta phase and gamma amplitude has been shown to be responsible for binding perceptual features to form representations. Theta-gamma coupling has been observed, for example, during the formation of visual associations (Köster, Finger, Graetz, Kater & Gruber, 2018), and was again higher for remembered than forgotten stimuli. Theta-gamma coupling has not yet been examined in infants due to methodological difficulties, such as contamination of the EEG signal by microsaccades (Köster, 2016) and low signal-to-noise ratio (Hoehl & Wahl, 2012). Since infants are in the process of building novel representations of their environment all the time, they are well-suited to show how early representations can begin to form. The current study introduces tools to solve these limitations and examines the neuronal processes related to forming new representations in 48 infants (6;12 - 8;04 months old). At the beginning of the experiment, infants were familiarised with four stimuli. They then saw interleaved trials showing either a familiar object or an entirely novel object. EEG was recorded continuously and wavelet transformed to time-frequency space. We expected that infants would show higher theta power for novel compared to familiar stimuli, and that theta-gamma coupling would be higher for novel compared to familiar stimuli. Our results show increased parietal and frontal theta for novel compared to familiar objects, in line with theta's role in building semantic conceptual networks. We were successful in removing microsaccade artifacts from the infant EEG and will further present the data on the cross-frequency coupling between theta phase and gamma amplitude. 1 p.

Predictive Processing accounts of autism claim that autistic individuals assign higher precision to their prediction errors than non-autistic individuals, that is, autistic individuals update their predictions more readily when faced with unexpected sensory input. Since setting the level of precision is a fundamental part of perception and learning, we propose that such differences should be detectable in various domains at a very early age, before clinical symptoms have fully emerged. We therefore tested 3-year-old younger siblings of autistic children, with a high likelihood of later receiving an autism diagnosis themselves, and low-likelihood children with an older sibling without autism. We used a novel implicit learning paradigm to examine the effect of sensory noise on the predictions participants built. In order to learn a sequence, our participants had to select which visual information to attend to and disregard low-level prediction errors caused by the sensory noise, which the theory claims is more difficult for autistic individuals. Contrary to the proposed higher precision-weighting of prediction errors in autism, the high-likelihood children did not show signs of updating their predictions more readily when we added sensory noise compared to the low-likelihood children, either in their reaction times or in the recurrence and determinism of their response locations. These results raise challenges for Predictive Processing theories of autism, specifically for the notion that prediction errors are inflexibly highly weighted by individuals with autism.

Predictive processing accounts of autism posit that individuals with autism rely less on expectations than those without autism when it comes to interpreting incoming sensory information. Since these expectations are claimed to underlie all information processing, we reason that any differences in how they are formed or adjusted should be persistent across multiple cognitive domains and detectable much earlier than clinicians can currently diagnose autism, around 3 years of age. This experiment is part of a longitudinal prospective study of young children with increased familial likelihood of autism. Around 20% of these children will receive an autism diagnosis, compared to 1% of the general population. The current electroencephalography study used an adaptation paradigm to investigate whether a reduced effect of expectations is already present in high-likelihood 2-year-olds, before autism can reliably be diagnosed. While we did not observe the adaptation aftereffect we expected, high-likelihood children habituated more than low-likelihood children, and the two groups did not differ in their overall responses to the manipulation, contrary to our hypotheses and previous findings. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

This study aimed to review the neurobiological and neuropsychological correlates of paranoid (persecutory delusions) and misidentification (misidentification delusions and/or hallucinations) subtypes of psychosis in dementia, to establish if they represent distinct subphenotypes. Nine studies were eligible, all included patients with Alzheimer’s disease. Greater global cognitive deficits and an accelerated global cognitive decline were observed in the misidentification subtype. Neuroimaging studies showed more marked volume loss in multiple regions in patients with the misidentification subtype, including those involved in object recognition and the processing of information on spatial and temporal context. A single study found greater impairment in visual sustained attention and object recognition in the misidentification subtype. The small number of studies and methodological heterogeneity limit interpretation of the findings. Nevertheless, these findings would tentatively suggest that there may be additional or accelerated pathological change in functional networks involved in visuoperceptual processing in the misidentification subtype. This should be further explored in prospective studies and the investigation extended to other forms of dementia, to gain a transdiagnostic perspective.

Older adults often show greater implicit/unconscious memory than young adults for incidental information that was task-irrelevant during its acquisition. Shallow/perceptual encoding by older adults may boost performance on implicit tasks that reinstate this type of processing, whereas deeper/conceptual encoding by young adults may support greater explicit/conscious memory. To test this, young and older participants were exposed to incidental words in a text color identification task before the trial-by-trial capture of priming and recognition. In Experiments 1-3 priming and recognition were significantly greater in young than older adults, providing evidence against age differences in encoding style. In Experiments 2-3 older adults were more liberal than young adults in making positive recognition judgments to incidental relative to intentional items, even though source memory was poor in both groups. Findings pinpoint age differences in the utilization of previously incidental versus intentional information on different types of task.

Context Appropriate management of adrenal insufficiency (AI) in pregnancy can be challenging due to the rarity of the disease and lack of evidence-based recommendations to guide glucocorticoid and mineralocorticoid dosage adjustment. Objective Multicenter survey on current clinical approaches in managing AI during pregnancy. Design Retrospective anonymized data collection from 19 international centers from 2013 to 2019. Setting and Patients 128 pregnancies in 113 women with different causes of AI: Addison disease (44%), secondary AI (25%), congenital adrenal hyperplasia (25%), and acquired AI due to bilateral adrenalectomy (6%). Results Hydrocortisone (HC) was the most commonly used glucocorticoid in 83% (97/117) of pregnancies. Glucocorticoid dosage was increased at any time during pregnancy in 73/128 (57%) of cases. In these cases, the difference in the daily dose of HC equivalent between baseline and the third trimester was 8.6 ± 5.4 (range 1-30) mg. Fludrocortisone dosage was increased in fewer cases (7/54 during the first trimester, 9/64 during the second trimester, and 9/62 cases during the third trimester). Overall, an adrenal crisis was reported in 9/128 (7%) pregnancies. Cesarean section was the most frequent mode of delivery at 58% (69/118). Fetal complications were reported in 3/120 (3%) and minor maternal complications in 15/120 (13%) pregnancies without fatal outcomes. Conclusions This survey confirms good maternal and fetal outcome in women with AI managed in specialized endocrine centers. An emphasis on careful endocrine follow-up and repeated patient education is likely to have reduced the risk of adrenal crisis and resulted in positive outcomes.

ObjectiveTo review evidence evaluating the use of multicomponent frailty assessment tools in assessing frailty in older adults with psychiatric disorders.MethodsA systematic literature review was conducted to identify all multicomponent frailty assessment tools (ie, a tool that assesses two or more indicators of frailty). The items of each frailty assessment tool were compared with Diagnostic and Statistical Manual of Mental Disorders, 5th edition (DSM‐5) diagnostic criteria for psychiatric disorders to assess construct overlap. Studies conducted in community, inpatient, and outpatient clinical settings were considered for inclusion.ParticipantsAdults aged 60 years or older.ResultsA total of 5639 records were identified following the removal of duplicates, from which 95 studies were included for review. Of the 48 multicomponent frailty assessment tools identified, no tool had been developed for, or validated in, older adult populations with a psychiatric disorder. Overall, 20 of 48 frailty assessment tools contained a psychological assessment domain, with 17 of 48 tools citing the presence of depressed mood and/or anxiety as a frailty indicator. Common areas of construct overlap in frailty assessment tools and DSM‐5 diagnostic criteria included weight loss (29 of 48) and fatigue (21 of 48).ConclusionsSignificant construct overlap exists between the indicators of frailty as conceptualized in existing frailty assessment tools and DSM‐5 diagnostic criteria for common psychiatric disorders including major depressive episode and generalized anxiety disorder that has the potential to confound frailty assessment results. Further research is necessary to establish a reliable and valid tool to assess frailty in this population. J Am Geriatr Soc, 1–11, 2018.

Contains fulltext : 232366.pdf (Publisher’s version ) (Open Access) Most theoretical accounts of autism posit difficulties in predicting others' actions, and this difficulty has been proposed to be at the root of autistic individuals’ social communication differences. Empirical results are mixed, however, with autistic individuals showing reduced action prediction in some studies but not in others. It has recently been proposed that this effect might be observed primarily when observed actions are less predictable, but this idea has yet to be tested. To assess the influence of predictability on neural and behavioural action prediction, the current study employed an action observation paradigm with multi-step actions that become gradually more predictable. Autistic and non-autistic adolescents showed similar patterns of motor system activation during observation, as seen in attenuated mu and beta power compared to baseline, with beta power further modulated by predictability in both groups. Bayesian statistics confirmed that action predictability influenced beta power similarly in both groups. The groups also made similar behavioural predictions, as seen in three eye-movement measures. We found no evidence that autistic adolescents responded differently than non-autistic adolescents to the predictability of an observed action. These findings show that autistic adolescents do spontaneously predict others’ actions, both neurally and behaviourally, which calls into question the role of action prediction as a key mechanism underlying autism. 10 p.

Item does not contain fulltext Recent accounts of autism claim that due to altered predictive processing, autistic individuals cannot always identify signal from noise in sensory input, which leads to models of the world that are overfitted to specific experiences (Manning et al., 2015; van der Cruys et al., 2017). According to these accounts, information processing differences should be present at a very young age, even before autism can be reliably diagnosed. Due to the hereditary nature of autism, we can currently study the development of the condition by following younger siblings of autistic children. Here, we examined whether these younger siblings have difficulty in distinguishing signal from noise, by manipulating sensory noise in a touchscreen Serial Reaction Time Task (SRTT). In the task, a picture of a frog appeared in a sequence (see Figure 1), and the children were asked to press the frog. In block 1, the sequence was identical on every repetition, while in block 3, the frog's exact location included random jitter; it was possible to learn which lilypad the frog would appear on next, but not precisely where on the lilypad it would appear. According to Predictive Processing accounts of autism, high-risk siblings should show difficulty separating signal from noise, and should thus learn the pattern slower in the block with added jitter. This should be especially pronounced in the children who receive an autism diagnosis themselves. Data collection is ongoing, but so far the results suggest that high-risk children (N=12) do in fact learn the pattern when there is additional noise added to the signal. This is contrary to previous findings (Manning et al., 2015; van der Cruys et al., 2017) and raises questions around when autistic children’s performance is and is not influenced by noise in the signal. 1 p.

It is well documented that explicit (declarative, conscious) memory declines in normal aging. Studies have shown a progressive reduction in this form of memory with age, and healthy older adults (typically aged 65+ years) usually perform worse than younger adults (typically aged 18–30 years) on laboratory tests of explicit memory such as recall and recognition. In contrast, it is less clear whether implicit (procedural, unconscious) memory declines or remains stable in normal aging. Implicit memory is evident when previous experiences affect (e.g., facilitate) performance on tasks that do not require conscious recollection of those experiences. This can manifest in rehearsed motor skills, such as playing a musical instrument, but is typically indexed in the laboratory by the greater ease with which previously studied information is processed relative to non-studied information (e.g., repetition priming). While a vast amount of research has accumulated to suggest that implicit memory remains relatively stable over the adult lifespan, and is similar in samples of young and older adults, other studies have in contrast revealed that implicit memory is subject to age-related decline. Improving methods for determining whether implicit memory declines or remains stable with age is an important goal for future research, as the issue not only has significant implications for an aging society regarding interventions likely to ameliorate the effects of age-related explicit memory decline, but can also inform our theoretical understanding of human memory systems.

To systematically review the characteristics, validity and outcome measures of tasks that have been described in the literature as assessing pattern separation and pattern completion in humans. Electronic databases were searched for articles. Parameters for task validity were obtained from two reviews that described optimal task design factors to evaluate pattern separation and pattern completion processes. These were that pattern separation should be tested during an encoding task using abstract, never-before-seen visual stimuli, and pattern completion during a retrieval task using partial cues; parametric alteration of the degree of interference of stimuli or degradation of cues should be used to generate a corresponding gradient in behavioral output; studies should explicitly identify the specific memory domain under investigation (sensory/perceptual, temporal, spatial, affect, response, or language) and account for the contribution of other potential attributes involved in performance of the task. A systematic, qualitative assessment of validity in relation to these parameters was performed, along with a review of general validity and task outcome measures. Sixty-two studies were included. The majority of studies investigated pattern separation and most tasks were performed on young, healthy adults. Pattern separation and pattern completion were most frequently tested during a retrieval task using familiar or recognizable visual stimuli and cues. Not all studies parametrically altered the degree of stimulus interference or cue degradation, or controlled for potential confounding factors. This review found evidence that some of the parameters for task validity have been followed in some human studies of pattern separation and pattern completion, but no study was judged to have adequately met all the parameters for task validity. The contribution of these parameters and other task design factors towards an optimal behavioral paradigm is discussed and recommendations for future research are made. © 2015 Wiley Periodicals, Inc.

Background Predictor analyses of late-life depression can be used to identify variables associated with outcomes of treatments, and hence ways of tailoring specific treatments to patients. The aim of this review was to systematically identify, review and meta-analyse predictors of outcomes of any type of treatment for late-life depression.Methods Pubmed, Embase, CINAHL, Web of Science and PsycINFO were searched for studies published up to December 2016. Primary and secondary studies reported treatment predictors from randomised controlled trials of any treatment for patients with major depressive disorder aged over 60 were included. Treatment outcomes included response, remission and change in depression score.ResultsSixty-seven studies met the inclusion criteria. Of 65 identified statistically significant predictors, only 7 were reported in at least 3 studies. Of these, 5 were included in meta-analyses, and only 3 were statistically significant. Most studies were rated as being of moderate to strong quality and satisfied key quality criteria for predictor analyses.LimitationsThe searches were limited to randomised controlled trials and most of the included studies were secondary analyses.ConclusionsBaseline depression severity, co-morbid anxiety, executive dysfunction, current episode duration, early improvement, physical illnesses and age were reported as statistically significant predictors of treatment outcomes. Only the first three were significant in meta-analyses. Subgroup analyses showed differences in predictor effect between biological and psychosocial treatment. However, high heterogeneity and small study numbers suggest a cautious interpretation of results. These predictors were associated with various mechanisms including brain pathophysiology, perceived social support and proposed distinct types of depressive disorder. Further investigation of the clinical utility of these predictors is suggested.

Reinstatement of encoding context facilitates memory for targets in young and older individuals (e.g., a word studied on a particular background scene is more likely to be remembered later if it is presented on the same rather than a different scene or no scene), yet older adults are typically inferior at recalling and recognizing target–context pairings. This study examined the mechanisms of the context effect in normal aging. Age differences in word recognition by context condition (original, switched, none, new), and the ability to explicitly remember target–context pairings were investigated using word–scene pairs (Experiment 1) and word–word pairs (Experiment 2). Both age groups benefited from context reinstatement in item recognition, although older adults were significantly worse than young adults at identifying original pairings and at discriminating between original and switched pairings. In Experiment 3, participants were given a three-alternative forced-choice recognition task that allowed older individuals to draw upon intact familiarity processes in selecting original pairings. Performance was age equivalent. Findings suggest that heightened familiarity associated with context reinstatement is useful for boosting recognition memory in aging.

Decision-making is a dynamic skill rather than a static capacity (Dhami et al., 2011), and so may alter on a developmental scale. A reduction in cognitive functioning has been linked to suboptimal decisions in older adults (Finucane et al., 2000). For example, declines in memory (Ratcliff et al., 1992), perceptual processing (Ratcliff et al., 2006), and inhibition (Williams et al., 1999) have been related to impairment in decision-making competence. Despite this, older individuals are regularly required to make important life decisions, such as choosing a medical treatment or retirement plan.

Background Frailty is widely recognised as a distinct multifactorial clinical syndrome that implies vulnerability. The links between frailty and adverse outcomes such as death and institutionalisation have been widely evidenced. There is currently no gold standard frailty assessment tool; optimizing the assessment of frailty in older people therefore remains a research priority. The objective of this systematic review is to identify existing multi-component frailty assessment tools that were specifically developed to assess frailty in adults aged ≥60 years old and to systematically and critically evaluate the reliability and validity of these tools. Methods A systematic literature review was conducted using the standardised COnsensus‐based Standards for the selection of health Measurement INstruments (COSMIN) checklist to assess the methodological quality of included studies. Results Five thousand sixty-three studies were identified in total: 73 of which were included for review. 38 multi-component frailty assessment tools were identified: Reliability and validity data were available for 21 % (8/38) of tools. Only 5 % (2/38) of the frailty assessment tools had evidence of reliability and validity that was within statistically significant parameters and of fair-excellent methodological quality (the Frailty Index-Comprehensive Geriatric Assessment [FI-CGA] and the Tilburg Frailty Indicator [TFI]). Conclusions The TFI has the most robust evidence of reliability and validity and has been the most extensively examined in terms of psychometric properties. However, there is insufficient evidence at present to determine the best tool for use in research and clinical practice. Further in-depth evaluation of the psychometric properties of these tools is required before they can fulfil the criteria for a gold standard assessment tool. Electronic supplementary material The online version of this article (doi:10.1186/s12877-016-0225-2) contains supplementary material, which is available to authorized users.

To systematically review the characteristics, validity and outcome measures of tasks that have been described in the literature as assessing pattern separation and pattern completion in humans. Electronic databases were searched for articles. Parameters for task validity were obtained from two reviews that described optimal task design factors to evaluate pattern separation and pattern completion processes. These were that pattern separation should be tested during an encoding task using abstract, never-before-seen visual stimuli, and pattern completion during a retrieval task using partial cues; parametric alteration of the degree of interference of stimuli or degradation of cues should be used to generate a corresponding gradient in behavioral output; studies should explicitly identify the specific memory domain under investigation (sensory/perceptual, temporal, spatial, affect, response, or language) and account for the contribution of other potential attributes involved in performance of the task. A systematic, qualitative assessment of validity in relation to these parameters was performed, along with a review of general validity and task outcome measures. Sixty-two studies were included. The majority of studies investigated pattern separation and most tasks were performed on young, healthy adults. Pattern separation and pattern completion were most frequently tested during a retrieval task using familiar or recognizable visual stimuli and cues. Not all studies parametrically altered the degree of stimulus interference or cue degradation, or controlled for potential confounding factors. This review found evidence that some of the parameters for task validity have been followed in some human studies of pattern separation and pattern completion, but no study was judged to have adequately met all the parameters for task validity. The contribution of these parameters and other task design factors towards an optimal behavioral paradigm is discussed and recommendations for future research are made. © 2015 Wiley Periodicals, Inc.

The use of previously distracting information on memory tests with indirect instructions is usually age-equivalent, while young adults typically show greater explicit memory for such information. This could reflect qualitatively distinct initial processing (encoding) of distracting information by younger and older adults, but could also be caused by greater suppression of such information by younger adults on tasks with indirect instructions. In Experiment 1, young and older adults read stories containing distracting words, which they ignored, before studying a list of words containing previously distracting items for a free recall task. Half the participants were informed of the presence of previously distracting items in the study list prior to recall (direct instruction), and half were not (indirect instruction). Recall of previously distracting words was age-equivalent in the indirect condition, but young adults recalled more distracting words in the direct condition. In Experiment 2, participants performed the continuous identification with recognition task, which captures a measure of perceptual priming and recognition on each trial, and is immune to suppression. Priming and recognition of previously distracting words was greater in younger than older adults, suggesting that the young engage in more successful suppression of previously distracting information on tasks in which its relevance is not overtly signaled.

resources, but is an acknowledged component of the BGS remit. During February alone, the BGS received reports of 19 sinkholes. The majority of these occurred in the Cretaceous Chalk of southern England. Approximately half were not naturally occurring sinkholes, but were due to the collapse of anthropogenic features. Typically, the anthropogenic subsidence collapse features included: the collapse of chalk shafts associated with historic extraction of chalk for brickworks; the collapse of deneholes (medieval chalk workings for chalk for ground improvement), and chalk mine shaft collapses. This paper describes the National Karst Database, stakeholder requirements, and how the BGS has responded with new and improved mechanisms for data collection, storage and dissemination.

39 patients completed the questionnaire. 30 patients (77%) said they received information regarding side-effects when ATD were commenced; 8 patients (21%) said they did not; and 1 patient (3%) was unsure. Most information was given verbally (32), and others include letters (11), cards (9) and leaflets (1). Only 19 patients (49%) said the information given was understandable (Fig.1). Most patients had not experienced side-effects (18). The most common side-effects reported were sore throat (8), lethargy, and malaise (6). When asked what they would do in the event of a sore throat, most patients (62%) said they will see their GP or attend A+E. Only 7 patients (18%) knew that they needed a blood test. Most patients said they would obtain medical input immediately (36%) or same day (36%). Only 20 patients (51%) said they would stop ATD in the event of a sore throat (Fig.2), and 18 patients (46%) knew to restart ATD if blood test was normal.

Onchocerciasis (river blindness), caused by the filarial nematode Onchocerca volvulus , is a major cause of visual impairment and dermatitis in sub-Saharan Africa. As O. volvulus contains an obligatory bacterial symbiont ( Wolbachia ), it is susceptible to antibiotic chemotherapy, although current regimens are considered too prolonged for community-level control programs. The aim of this study was to compare the efficacies of oxytetracycline and rifampin, administered separately or in combination, against a close relative of O. volvulus ( Onchocerca ochengi ) in cattle. Six animals per group were treated with continuous or intermittent oxytetracycline regimens, and effects on adult worm viability, dermal microfilarial loads, and Wolbachia density in worm tissues were assessed. Subsequently, the efficacies of 3-week regimens of oxytetracycline and rifampin alone and a combination regimen were compared, and rifampin levels in plasma and skin were quantified. A 6-month regimen of oxytetracycline with monthly dosing was strongly adulticidal, while 3-week and 6-week regimens exhibited weaker adulticidal effects. However, all three regimens achieved >2-log reductions in microfilarial load. In contrast, rifampin monotherapy and oxytetracycline-rifampin duotherapy failed to induce substantive reductions in either adult worm burden or microfilarial load, although a borderline effect on Wolbachia density was observed following duotherapy. Dermal rifampin levels were maintained above the MIC for >24 h after a single intravenous dose. We conclude that oxytetracycline-rifampin duotherapy is less efficacious against O. ochengi than oxytetracycline alone. Further studies will be required to determine whether rifampin reduces oxytetracycline bioavailability in this system, as suggested by human studies using other tetracycline-rifampin combinations.

Recognition memory is typically weaker in healthy older relative to young adults, while performance on implicit tests (e.g., repetition priming) is often comparable between groups. Such observations are commonly taken as evidence for independent explicit and implicit memory systems. On a picture version of the continuous identification with recognition (CID-R) task, we found a reliable age-related reduction in recognition memory, while the age effect on priming did not reach statistical significance (Experiment 1). This pattern was consistent with the predictions of a formal single-system model. Experiment 2 replicated these observations using separate priming (continuous identification; CID) and recognition phases, while a combined data analysis revealed a significant effect of age on priming. In Experiment 3, we provide evidence that priming in this task is unaffected by explicit processing, and we conclude that the age difference in priming is unlikely to have been driven by differences in explicit processing between groups of young and older adults ("explicit contamination"). The results support the view that explicit and implicit expressions of memory are driven by a single underlying memory system.

It is well documented that explicit memory (e.g., recognition) declines with age. In contrast, many argue that implicit memory (e.g., priming) is preserved in healthy aging. For example, priming on tasks such as perceptual identification is often not statistically different in groups of young and older adults. Such observations are commonly taken as evidence for distinct explicit and implicit learning/memory systems. In this article we discuss several lines of evidence that challenge this view. We describe how patterns of differential age-related decline may arise from differences in the ways in which the two forms of memory are commonly measured, and review recent research suggesting that under improved measurement methods, implicit memory is not age-invariant. Formal computational models are of considerable utility in revealing the nature of underlying systems. We report the results of applying single and multiple-systems models to data on age effects in implicit and explicit memory. Model comparison clearly favours the single-system view. Implications for the memory systems debate are discussed.