Incremental learning of independent, overlapping, and graded concept descriptions with an instance-based process framework

Supervised learning algorithms make several simplifying assumptions concerning the characteristics of the concept descriptions to be learned. For example, concepts are often assumed to be (1) defined with respect to the same set of relevant attributes, (2) disjoint in instance space, and (3) have uniform instance distributions. While these assumptions constrain the learning task, they unfortunately limit an algorithm's applicability. We believe that supervised learning algorithms should learn attribute relevancies independently for each concept, allow instances to be members of any subset of concepts, and represent graded concept descriptions. This paper introduces a process framework for instance-based learning algorithms that exploit only specific instance and performance feedback information to guide their concept learning processes. We also introduce Bloom, a specific instantiation of this framework. Bloom is a supervised, incremental, instance-based learning algorithm that learns relative attribute relevancies independently for each concept, allows instances to be members of any subset of concepts, and represents graded concept memberships. We describe empirical evidence to support our claims that Bloom can learn independent, overlapping, and graded concept descriptions

Post‐diagnosis adiposity, physical activity, sedentary behaviour, dietary factors, supplement use and colorectal cancer prognosis: Global Cancer Update Programme ( CUP Global) summary of evidence grading

Based on the World Cancer Research Fund Global Cancer Update Programme, we performed systematic reviews and meta‐analyses to investigate the association of post‐diagnosis adiposity, physical activity, sedentary behaviour, and dietary factors with colorectal cancer prognosis. We searched PubMed and Embase until 28th February, 2022. An independent expert committee and expert panel graded the quality of evidence. A total of 167 unique publications were reviewed, and all but five were observational studies. The quality of the evidence was graded conservatively due to the high risk of several biases. There was evidence of non‐linearity in the associations between body mass index and colorectal cancer prognosis. The associations appeared reverse J‐shaped, and the quality of this evidence was graded as limited (likelihood of causality: limited‐no conclusion). The evidence on recreational physical activity and lower risk of all‐cause mortality (relative risk [RR] highest vs. lowest: 0.69, 95% confidence interval [CI]: 0.62–0.77) and recurrence/disease‐free survival (RR: 0.80, 95% CI: 0.70–0.92) was graded as limited‐suggestive. There was limited‐suggestive evidence for the associations between healthy dietary and/or lifestyle patterns (including diets that comprised plant‐based foods), intake of whole grains and coffee with lower risk of all‐cause mortality, and between unhealthy dietary patterns and intake of sugary drinks with higher risk of all‐cause mortality. The evidence for other exposures on colorectal cancer outcomes was sparse and graded as limited‐no conclusion. Analyses were conducted excluding cancer patients with metastases without substantial changes in the findings. Well‐designed intervention and cohort studies are needed to support the development of lifestyle recommendations for colorectal cancer patients

Associative Processes in Statistical Learning: Paradoxical Predictions of the Past

The ability to process sequences of input and extract regularity across the distribution of input is fundamental for making predictions from the observed past to the future. Prediction is rooted in the extraction of both frequency- and conditional statistics from the distribution of inputs. For example, an animal hunting for food may consistently return to a particular area to hunt if relative to all other areas visited, that area has the highest frequency of prey. In contrast, humans asked to predict the next word in a sentence must make a prediction based upon higher-order regularities rather than simple frequency statistics (the most frequent word in the English language is the). The Serial Reaction Time (SRT) task, a model for studying sequential behavior, is used to quantify sensitivity to sequential constraints present in structured environments (Nissen & Bullemer, 1987). The SRT task requires Ss to make a unique response to each individually presented element from a sequence of elements. The statistics of SRT sequences, such as the relative frequency of elements and simple pairwise associations between elements, can be controlled to create dependencies that can only be predicted by learning higher-order associations. Sensitivity to the sequential constraints present in the structured input is demonstrated through differences in reaction time to elements that are, and are not, predictable based upon the statistics of the input environment. Sensitivity to statistical regularity in the environment is also a critical dimension of various episodic learning methodologies. Graded associations have been demonstrated among elements extending in both forward and backward directions in episodic memory tasks, and are suggested to reflect a gradient of the underlying structural relationships among the study elements. Graded associations are beneficial to the extent that they increase the probability of recalling sequence elements.However, unlike free and serial recall tasks, backward associations, and remote associations in general, are anti-predictive in the SRT task. The formation of associations beyond the immediately predictive element in prediction tasks could be suggestive of a ubiquitous underlying associative mechanism, which universally gives rise to graded contiguity effects, regardless of the specifc application (Howard, Jing, Rao, Provyn, & Datey, 2009). The following experiment employed a probabilistic SRT task to quantify sensitivity to immediately backward, backward-remote, and forward-remote associations. Ss were presented sequences of elements probabilistically sampled from an underlying ring-structure, with the dependent measure Ss\u27 reaction time to elements that either followed, or deviated from, the structure. Results from the SRT task indicated that Ss demonstrated a robust backward association, as well as evidence for forward-graded associations. Moreover, in an explicit test of sequence knowledge, while Ss did not generate the probabilistic statistics from the structured learning environment, Ss did generate a statistically signifcant amount of backward-transitions, relative to other remote-backward transitions. The graded associations that were formed beyond the immediately predictive element in the prediction task provide evidence that a similar mechanism that mediates episodic learning may also mediate statistical learning. Backward and graded associations may be explained by a ubiquitous underlying associative mechanism, which universally gives rise to graded contiguity effects, regardless of the specific application

Alcohol consumption and mortality from all causes, coronary heart disease, and stroke: results from a prospective cohort study of Scottish men with 21 years of follow up

Objectives: To relate alcohol consumption to mortality. Design: Prospective cohort study. Setting: 27 workplaces in the west of Scotland. Participants: 5766 men aged 35-64 when screened in 1970-3 who answered questions on their usual weekly alcohol consumption. Main outcome measures: Mortality from all causes, coronary heart disease, stroke, and alcohol related causes over 21 years of follow up related to units of alcohol consumed per week. Results: Risk for all cause mortality was similar for non-drinkers and men drinking up to 14 units a week. Mortality risk then showed a graded association with alcohol consumption (relative rate compared with non-drinkers 1.34 (95% confidence interval 1.14 to 1.58) for 15-21 units a week, 1.49 (1.27 to 1.75) for 22-34 units, 1.74 (1.47 to 2.06) for 35 or more units). Adjustment for risk factors attenuated the increased relative risks, but they remained significantly above 1 for men drinking 22 or more units a week. There was no strong relation between alcohol consumption and mortality from coronary heart disease after adjustment. A strong positive relation was seen between alcohol consumption and risk of mortality from stroke, with men drinking 35 or more units having double the risk of non-drinkers, even after adjustment. Conclusions: The overall association between alcohol consumption and mortality is unfavourable for men drinking over 22 units a week, and there is no clear evidence of any protective effect for men drinking less than this

Cortical coding

The encoding of information in the primate inferior temporal visual cortex, hippocampus, orbitofrontal cortex, and insula is described. All these areas have sparse distributed graded firing rate representations. The firing rate probability distribution is close to exponential. The information increases approximately linearly with the number of neurons. Consistent with this relative independence, there is little extra information that is available because of stimulus-dependent synchrony, and little redundancy. The code can be read very fast, in 20–50 ms, by dot-product, biologically plausible decoding. The advantages of this code include high capacity, generalisation, graceful degradation, and rapid readout of the information by biologically plausible dot-product decoding. None of these are properties of local or “grandmother-cell’ representations. Consistent evidence is becoming available for humans. These sparse distributed graded firing rate representations have major computational advantages for the brain including for language that are not met by local or ‘grandmother-cell’ representations

Temporally Graded Activation of Neocortical Regions in Response to Memories of Different Ages

The temporally graded memory impairment seen in many neurobehavioral disorders implies different neuroanatomical pathways and/or cognitive mechanisms involved in storage and retrieval of memories of different ages. A dynamic interaction between medial-temporal and neocortical brain regions has been proposed to account for memory\u27s greater permanence with time. Despite considerable debate concerning its time-dependent role in memory retrieval, medial-temporal lobe activity has been well studied. However, the relative participation of neocortical regions in recent and remote memory retrieval has received much less attention. Using functional magnetic resonance imaging, we demonstrate robust, temporally graded signal differences in posterior cingulate, right middle frontal, right fusiform, and left middle temporal regions in healthy older adults during famous name identification from two disparate time epochs. Importantly, no neocortical regions demonstrated greater response to older than to recent stimuli. Our results suggest a possible role of these neocortical regions in temporally dating items in memory and in establishing and maintaining memory traces throughout the lifespan. Theoretical implications of these findings for the two dominant models of remote memory functioning (Consolidation Theory and Multiple Trace Theory) are discussed

Therapists\u27 use of the graded repetitive arm supplementary program (GRASP) intervention: A practice implementation survey study

The aims of this study were: (1) to explore the extent of practice implementation of GRASP in the United Kingdom; (2) using an implementation framework, to explore UK therapists\u27 opinions of implementing GRASP; and (3) if GRASP is found to be used in the United Kingdom, to investigate differences in opinions between therapists who are using GRASP in practice and those who are not

Lithology and the evolution of bedrock rivers in post-orogenic settings: Constraints from the high elevation passive continental margin of SE Australia

Understanding the role of lithological variation in the evolution of topography remains a fundamental issue, especially in the neglected post-orogenic terrains. Such settings represent the major part of the Earth's surface and recent modelling suggests that a range of interactions can account for the presence of residual topography for hundreds of millions of years, thereby explaining the great antiquity of landscapes in such settings. Field data from the inland flank of the SE Australian high-elevation continental margin suggest that resistant lithologies act to retard or even preclude the headward transmission of base-level fall driven by the isostatic response to regional denudation. Rejuvenation, be it episodic or continuous, is ‘caught up’ on these resistant lithologies, meaning in effect that the bedrock channels and hillslopes upstream of these ‘stalled’ knickpoints have become detached from the base-level changes downstream of the knickpoints. Until these knickpoints are breached, therefore, catchment relief must increase over time, a landscape evolution scenario that has been most notably suggested by Crickmay and Twidale. The role of resistant lithologies indicates that detachment-limited conditions are a key to the longevity of some post-orogenic landscapes, whereas the general importance of transport-limited conditions in the evolution of post-orogenic landscapes remains to be evaluated in field settings. Non-steady-state landscapes may lie at the heart of widespread, slowly evolving post-orogenic settings, such as high-elevation passive continental margins, meaning that non-steady-state landscapes, with increasing relief through time, are the ‘rule’ rather than the exception

The effects of graded motor imagery and its components on chronic pain: A systematic review and meta-analysis

This is the post-print version of the final paper published in The Journal of Pain. The published article is available from the link below. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. Copyright @ 2013 The American Pain Society.Graded motor imagery (GMI) is becoming increasingly used in the treatment of chronic pain conditions. The objective of this systematic review was to synthesize all evidence concerning the effects of GMI and its constituent components on chronic pain. Systematic searches were conducted in 10 electronic databases. All randomized controlled trials (RCTs) of GMI, left/right judgment training, motor imagery, and mirror therapy used as a treatment for chronic pain were included. Methodological quality was assessed using the Cochrane risk of bias tool. Six RCTs met our inclusion criteria, and the methodological quality was generally low. No effect was seen for left/right judgment training, and conflicting results were found for motor imagery used as stand-alone techniques, but positive effects were observed for both mirror therapy and GMI. A meta-analysis of GMI versus usual physiotherapy care favored GMI in reducing pain (2 studies, n = 63; effect size, 1.06 [95% confidence interval, .41, 1.71]; heterogeneity, I2 = 15%). Our results suggest that GMI and mirror therapy alone may be effective, although this conclusion is based on limited evidence. Further rigorous studies are needed to investigate the effects of GMI and its components on a wider chronic pain population.NHMR