Research in the design of high-performance reconfigurable systems

The initial control and programming philosophies of the RELAPSE are discussed. A block diagram showing the relationship of the Arithmetic Units (composed of Stages and Bit Processors), to the Functional Units, and other components of the RELAPSE is used to guide this discussion. The latest version of the Bit Processor design is presented. Included is a detailed discussion of the Bit Processor's new scratch pad memory component. The section also clarifies the usage of the Bit Processor's processing registers, and Input/Output functions. The final design phase of the Arithmetic Unit is underway by a study of the Proposed IEEE Floating Point Standard. The decisions on conformation to this standard will be used as inputs into the finalization of the designs of the Bit Processor, Stage, and Arithmetic Units of the RELAPSE

Research in the design of high-performance reconfigurable systems

An initial design for the Bit Processor (BP) referred to in prior reports as the Processing Element or PE has been completed. Eight BP's, together with their supporting random-access memory, a 64 k x 9 ROM to perform addition, routing logic, and some additional logic, constitute the components of a single stage. An initial stage design is given. Stages may be combined to perform high-speed fixed or floating point arithmetic. Stages can be configured into a range of arithmetic modules that includes bit-serial one or two-dimensional arrays; one or two dimensional arrays fixed or floating point processors; and specialized uniprocessors, such as long-word arithmetic units. One to eight BP's represent a likely initial chip level. The Stage would then correspond to a first-level pluggable module. As both this project and VLSI CAD/CAM progress, however, it is expected that the chip level would migrate upward to the stage and, perhaps, ultimately the box level. The BP RAM, consisting of two banks, holds only operands and indices. Programs are at the box (high-level function) and system level. At the system level initial effort has been concentrated on specifying the tools needed to evaluate design alternatives

Conscious Processing During Retrieval Can Occur in Early and Late Visual Regions

Previous evidence has suggested a functional-anatomic dissociation between conscious and nonconscious processing during retrieval where early visual regions BA17/18 are associated with nonconscious processing and late visual regions BA19/37 are associated with conscious processing. However, evidence for this dissociation has only been observed using a limited number of experimental paradigms. In the present functional magnetic resonance imaging (fMRI) study, we tested the hypothesis that conscious processing during retrieval can occur in BA17/18 using memorial paradigms that recruited processing in these early visual regions. During the encoding phase of Experiment 1, abstract shapes with colored and oriented internal lines were presented to the left and right of fixation. During the retrieval phase, old shapes and new shapes were presented at fixation and participants classified each item as “old-left”, “old-right”, or “new”. The contrast of spatial memory-hits>spatial memory-misses (with accurate item memory) produced activity in BA17/18. During the encoding phase of Experiment 2, abstract shapes with colored and oriented internal lines were presented at fixation. During the retrieval phase, old shapes, changed shapes (with the same outline but different colored and oriented internal lines), and new shapes were presented at fixation and participants made an old-new classification during runs with a specific retrieval orientation or a non-specific retrieval orientation. Critically, the contrast of old-hits>old-misses during specific retrieval orientation produced activity in BA17/18. The results of the present experiments support the hypothesis that conscious processing during retrieval can occur in BA17/18.Psycholog

Two Forms of Spatial Imagery: Neuroimaging Evidence ​

Spatial imagery may be useful in such tasks as interpreting graphs and solving geometry problems, and even in performing surgery. This study provides evidence that spatial imagery is not a single faculty; rather, visualizing spatial location and mentally transforming location rely on distinct neural networks. Using 3-T functional magnetic resonance imaging, we tested 16 participants (8 male, 8 female) in each of two spatial imagery tasks--one that required visualizing location and one that required mentally rotating stimuli. The same stimuli were used in the two tasks. The location-based task engendered more activation near the occipito-parietal sulcus, medial posterior cingulate, and precuneus, whereas the transformation task engendered more activation in superior portions of the parietal lobe and in the postcentral gyrus. These differences in activation provide evidence that there are at least two different types of spatial imagery.Psycholog

Under pressure: Response urgency modulates striatal and insula activity during decision-making under risk

When deciding whether to bet in situations that involve potential monetary loss or gain (mixed gambles), a subjective sense of pressure can influence the evaluation of the expected utility associated with each choice option. Here, we explored how gambling decisions, their psychophysiological and neural counterparts are modulated by an induced sense of urgency to respond. Urgency influenced decision times and evoked heart rate responses, interacting with the expected value of each gamble. Using functional MRI, we observed that this interaction was associated with changes in the activity of the striatum, a critical region for both reward and choice selection, and within the insula, a region implicated as the substrate of affective feelings arising from interoceptive signals which influence motivational behavior. Our findings bridge current psychophysiological and neurobiological models of value representation and action-programming, identifying the striatum and insular cortex as the key substrates of decision-making under risk and urgency

Increased ventral striatal volume in college-aged binge drinkers

BACKGROUND Binge drinking is a serious public health issue associated with cognitive, physiological, and anatomical differences from healthy individuals. No studies, however, have reported subcortical grey matter differences in this population. To address this, we compared the grey matter volumes of college-age binge drinkers and healthy controls, focusing on the ventral striatum, hippocampus and amygdala. METHOD T1-weighted images of 19 binge drinkers and 19 healthy volunteers were analyzed using voxel-based morphometry. Structural data were also covaried with Alcohol Use Disorders Identification Test (AUDIT) scores. Cluster-extent threshold and small volume corrections were both used to analyze imaging data. RESULTS Binge drinkers had significantly larger ventral striatal grey matter volumes compared to controls. There were no between group differences in hippocampal or amygdalar volume. Ventral striatal, amygdalar, and hippocampal volumes were also negatively related to AUDIT scores across groups. CONCLUSIONS Our findings stand in contrast to the lower ventral striatal volume previously observed in more severe forms of alcohol use disorders, suggesting that college-age binge drinkers may represent a distinct population from those groups. These findings may instead represent early sequelae, compensatory effects of repeated binge and withdrawal, or an endophenotypic risk factor

Internet-based medical education: a realist review of what works, for whom and in what circumstances

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Exploring deliberate practice in medicine: how do physicians learn in the workplace?

Medical professionals need to keep on learning as part of their everyday work to deliver high-quality health care. Although the importance of physicians’ learning is widely recognized, few studies have investigated how they learn in the workplace. Based on insights from deliberate practice research, this study examined the activities physicians engage in during their work that might further their professional development. As deliberate practice requires a focused effort to improve performance, the study also examined the goals underlying this behaviour. Semi-structured interviews were conducted with 50 internal medicine physicians: 19 residents, 18 internists working at a university hospital, and 13 working at a non-university hospital. The results showed that learning in medical practice was very much embedded in clinical work. Most relevant learning activities were directly related to patient care rather than motivated by competence improvement goals. Advice and feedback were sought when necessary to provide this care. Performance standards were tied to patients’ conditions. The patients encountered and the discussions with colleagues about patients were valued most for professional development, while teaching and updating activities were also valued in this respect. In conclusion, physicians’ learning is largely guided by practical experience rather than deliberately sought. When professionals interact in diagnosing and treating patients to achieve high-quality care, their experiences contribute to expertise development. However, much could be gained from managing learning opportunities more explicitly. We offer suggestions for increasing the focus on learning in medical practice and further research

Top-Down Feedback in an HMAX-Like Cortical Model of Object Perception Based on Hierarchical Bayesian Networks and Belief Propagation

PubMed ID: 2313976

Piloting online self-audit of methadone treatment in Irish general practice: results, reflections and educational outcomes

Background: Work based learning underpins the training and CPD of medical practitioners. Medical audit operates on two levels; individual self-assessment and professional/practice development. In Ireland, annual practice improvement audit is an essential requirement for the successful completion of continuous professional development (CPD) as determined by the regulatory body, the Irish Medical Council. All general practice (GP) doctors providing methadone maintenance treatment (MMT) in Ireland have a contractual obligation to partake in a yearly methadone practice audit. The Irish College of General Practitioners (ICGP) as national training provider is tasked to facilitate this annual audit process. The purpose of this audit is to assess the quality of care provided to patients against an agreed set of national standards, enhance learning, and promote practice improvement and reflective practice. The aim was to present an online MTP self-audit and evaluate results from a 12-month pilot among GPs providing MMT in Ireland. Method A mixed method study describing three phases (design and development, pilot/implementation and evaluation) of a new online self –audit tool was conducted. Descriptive and thematic analysis of audit and evaluation data was conducted. Results: Survey Monkey is a suitable software package for the development and hosting of an easy to use online audit for MMT providing doctors. Analysis of the audit results found that the majority of GPs scored 80% or over for the 25 identified essential criteria for MMT provision. The evaluation of the GP audit experience underscores the positive outcomes of the online self-audit in terms of improving practice systems, encouraging reflective practice, enhanced patient care and doctor commitment to continued provision of MMT in addiction clinics and in primary care. Conclusions: Results from this audit demonstrate a high level of compliance with best practise MMT guidelines by Irish GPs providing MMT. The online self-audit process was well received and encouraged reflective practice. The audit process hinged on the individual GP’s ability to review and critically analyse their professional practice, and manage change. This model of audit could be adapted and used to monitor the management of other chronic illnesses in general practice