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Erasing when drawing occurs for a variety of reasons. While the most obvious may be correction of mistakes, at other times erasers are used to create such things as highlights or marks that introduce particular aesthetic elements. When a drawing is made on paper, partial erasure ‘marks’ can provide a useful record of a drawing’s evolution. For the teacher, this historical record can be a catalyst for helpful commentary and criticism. While programmed to simulate an analogue eraser, in a digital environment the erase function can eradicate a drawing’s history with a single click. We studied analogue and digital tool use behaviours (including erasing) to compare the frequency of erasure and the effect of erasing on observational accuracy in adults between the age of 17 and 64 with various levels of drawing experience from less than two years to more than ten years. The study involved participants making one drawing on paper with traditional drawing tools and one drawing on a digital drawing tablet. We then had the drawings rated for accuracy. Among other interesting results, we found that erasing occurs with greater frequency when participants work in a digital environment than in an analogue one and that, while there were significant tool use differences between the environments, those differences did not result in differences in the accuracy of final drawings indicating the adaptability of our participants using different means to achieve the same effect.

This chapter describes the anaesthetic management of the patient with liver disease and its sequelae. Acute liver failure and chronic liver failure are discussed, together with their anaesthetic implications on coagulation and drug metabolism. Major sequelae of liver disease are discussed, including portal hypertension, varices, and hepatorenal syndrome. The pre-operative investigation and optimisation, treatment, and anaesthetic management of the patient with liver failure are described. The investigation and management of postoperative liver dysfunction are described.

The remotely operated electromechanical control device (ECD) is coupled to an open-close valve that would normally require hydraulic lines from surface. With each function of the valve, an intervention is eliminated, which increases operational efficiency and saves rig time. As these devices are permanently installed in severe downhole environments, design-in reliability is paramount. Reliability demonstration test (RDT) is a key element of the design-for-reliability process to verify that the product satisfies the system reliability target. This paper presents a structured RDT approach to demonstrate the reliability of a remotely operated ECD in a cost- and time-efficient manner. The reliability target of the ECD was established based on the tasks requirements (open-close functions), well conditions, and mission life. Key subassemblies of the ECD were identified, and a system reliability target was allocated to the subsystem level using a weight factor-based approach. A test-to-success methodology was used to design the RDT of individual subassemblies by identifying the underlying failure mechanism, applicable test stresses, and acceleration factors. A parametric cumulative binomial test design model was used to optimize the test parameters, such as sample size, test time, and number of valve open-close functions. Conducting a system reliability test is often cost prohibitive. Therefore, performing a reliability test at the subsystem level is an alternative approach of verifying system reliability. Reliability allocation weight factors are determined based on the cost, time, and relative difficulty in testing the design feature. Aging parameters were found to be the number of valve open-close functions based on the underlying tasks, operating time, and well environment (temperature). This paper highlights the structured methodology and application requirements of RDT to meet the mission reliability target of a remotely operated ECD. A comprehensive reliability target was established based on the underlying tasks, operating time, and well environment. A combination of overstress (temperature) and use-rate accelerations was used in the test design. An optimum value assessment of test design parameters was performed for developing a cost-effective test design. The approach and benefits of structured reliability test design are discussed in the paper.

The successful operation of completion tools, especially intelligent completion tools, at high pressure/high temperature (HPHT) operating conditions is dependent on reliable design and robust production and operating procedures. Recent technological advancements in high-temperature electronics can lead to changes in the production processes of existing completion products. Possible reasons for change include component obsolescence, consolidation of production processes, or leveraging technological advancements from one product to another. Verification of changes made in production processes is critical to maintain high operational reliability of the product. This paper presents a methodical test design approach to verify changes made in production processes in a cost- and time-efficient manner. The purpose of the Production Acceptance Test (PAT) is to provide assurance that the reliability of standard production items meets the reliability specifications. PAT usually involves testing of a sample of items drawn from a production batch. The results obtained from testing these samples enables an informed decision regarding the reliability of the entire production population. The concept and philosophy of PAT stems from the military handbook, MIL-HDBK-781, based on non-parametric distribution utilizing Mean-Time-Between-Failures (MTBF) as the performance criteria. To overcome the limitations of MTBF and non-parametric distribution, a modified test design methodology includes a comprehensive reliability statement of the product along with the use of parametric cumulative binomial distribution. Elements of PAT design (Discrimination Ratio (DR), producer's risk, consumer's risk, etc.) are assessed for developing high-temperature electronics for HPHT environments. A key prerequisite of employing PAT is to assess product reliability through either reliability test data or field operational data. A reliability specification of the product is an upfront requirement of designing PAT. The test design methodology presented utilizes comprehensive reliability statements in terms of % probability of success, % confidence, lifetime, and operating conditions. DR is another key element of PAT design and typically ranges from 1.5-3.0. However, for manufacturers with robust production processes and well planned management-of-change, DR lies somewhere in the range of 2.5-3.0. By selecting optimum values of test design parameters, an effective test plan can be developed which can result in time and cost savings compared to a standard reliability test. This paper discusses the methodology and application requirements to enhance PAT as a verification test to validate any changes in production processes. Test design methodologies are upgraded to include a comprehensive reliability statement along with the use of a parametric cumulative binomial algorithm to overcome the limitations of original PAT methodology highlighted in MIL-HDBK-781. Optimum value assessment of PAT design parameters was performed for developing high-temperature electronics used in HPHT environments. A case history of a downhole electronics module is presented to describe the enhanced approach and benefits of PAT.

The Gulf Cooperation Council (GCC), formed by six nations of the Arabian peninsula—Bahrain, Kuwait, Oman, Qatar, Saudi Arabia and the United Arab Emirates—is no exception to the general rule. The organizational structure of the GCC reflected the Council's collective view of the best means and methods for the new body to function to its maximum advantage. The GCC Secretariat General, headquartered in Riyadh, plays a significant and influential role in the GCC scheme of things; it has much of the power and style of the United Nations Secretariat-General. The GCC itself will give a stout affirmative to the questions and point to a dozen or more kindred characteristics of the peoples of the GCC states. The very existence of a combined military force confirms the GCC's oft-stated position: that an attack on any one GCC state will be regarded as an attack on all.

Conventional wisdom tells us that the appreciation of local (detail) and global (form and spatial relations) information from a scene is preferentially processed by central and peripheral vision, respectively. Using an eye monitor with high spatial and temporal precision, we sought to provide direct evidence for this idea by controlling whether carefully designed hierarchical scenes were viewed only with central vision (the periphery was masked), only with peripheral vision (the central region was masked), or with full vision. The scenes consisted of a neutral form (a D shape) composed of target circles or squares, or a target circle or square composed of neutral material (Ds). The task was for the participant to determine as quickly as possible whether the scene contained circle(s) or square(s). Increasing the size of the masked region had deleterious effects on performance. This deleterious effect was greater for the extraction of form information when the periphery was masked, and greater for the extraction of material information when central vision was masked, thus providing direct evidence for conventional ideas about the processing predilections of central and peripheral vision.

When participants search for a target letter while reading for comprehension, they miss more instances if the target letter is embedded in frequent function words than in less frequent content words. This phenomenon, called the missing-letter effect, has been considered a window on the cognitive mechanisms involved in the visual processing of written language. In the present study, one group of participants read two texts for comprehension while searching for a target letter, and another group listened to a narration of the same two texts while listening for the target letter’s corresponding phoneme. The ubiquitous missing-letter effect was replicated and extended to a missing-phoneme effect. Item-based correlations between the reading and listening tasks were high, which led us to conclude that both tasks involve cognitive processes that reading and listening have in common and that both processes are rooted in psycholinguistically driven allocation of attention.

This chapter describes the anaesthetic management of the patient with liver disease and its sequelae. Acute liver failure and chronic liver failure are discussed, together with their anaesthetic implications on coagulation and drug metabolism. Major sequelae of liver disease are discussed, including portal hypertension, varices, and hepatorenal syndrome. The preoperative investigation and optimization, treatment, and anaesthetic management of the patient with liver failure are described. The investigation and management of post-operative liver dysfunction are described. The anaesthetic management of acute oesophageal variceal haemorrhage and transjugular intrahepatic portosystemic shunt (TIPSS) are described.

Christie and Klein [2005. Does attention cause illusory line motion? Perception & Psychophysics, 67(6), 1032–1043] published line motion ratings consistent with illusory line motion (ILM) after peripheral endogenous cues but not central arrow cues. When attention was directed endogenously on the basis of the shape of one of two peripherally presented objects, participants reported small, but significant motion away from the attended object, and this was attributed to participant bias, or to a peripherally directed object-based attention system endogenously recruited to differentiate the peripheral shapes. By using a unique cueing method with identical peripheral markers, but still allowing them to act as cues, the findings of Christie and Klein Experiment 4 were replicated. This reduces the likelihood that object discrimination or object attention mechanisms are responsible for the reported ILM-like effects.

Osteosarcoma is the most common bone cancer and typically affects patients in the second decade of life. Current treatment methods have not proven effective for treating reoccurring or metastatic osteosarcoma (mOS) given the 5-year survival rate of 15–30%. Previous work has shown anti-PD-L1 combined with anti-CTLA-4 improves survival of mOS in mice from 0% in no treatment mice to 60% in treated mice. To further improve survival, we analyzed tumor infiltrating lymphocytes (TILs) in mice over time and discovered CD4hiCD8hiPD-1hi T cells consistently appeared in the tumor microenvironment (TME) after approximately two months. To determine whether these CD4hiCD8hi, or double positive (DP) cells, were candidates for immune therapy, TILs from mice with long-term cancer were stained for CD3 to confirm T cell lineage, CD44 to verify activation, and Qa-2, which is first expressed during the stage IV single positive phase of T cell maturation and is therefore a marker to distinguish mature from immature T cells. The DP TILs were found to be activated, mature T cells that are distinct from DP immature thymocytes. The DP TILs were further compared to splenocytes and were determined to be concentrated in the TME rather than resulting from a systemic change in the immune system. Finally, the presence of DP T cells in the lungs was found to be unique to long-term lung metastases when lung tissues from age-matched healthy mice were obtained and processed alongside experimental lung metastases. Overall, mature and activated DP T cells concentrate in the TME of long-term lung metastases of mOS.

Weapon focus is frequently cited as a factor in eyewitness testimony, and is broadly defined as a weapon-related decrease in performance on subsequent tests of memory for those elements of an event or visual scene concurrent to the weapon. This effect has been attributed to either (a) physiological or emotional arousal that narrows the attentional beam (arousal/threat hypothesis), or (b) the cognitive demands inherent in processing an unusual object (e.g. weapon) that is incongruent with the schema representing the visual scene (unusual item hypothesis). Meta-analytical techniques were applied to test these theories as well as to evaluate the prospect of weapon focus in real-world criminal investigations. Our findings indicated an effect of weapon presence overall (g= 0.53) that was significantly influenced by retention interval, exposure duration, and threat but unaffected by whether the event occurred in a laboratory, simulation, or real-world environment.

Decades of research using Posner’s classic spatial cueing paradigm has uncovered at least two forms of inhibition of return (IOR) in the aftermath of an exogenous, peripheral orienting cue. One prominent dissociation concerns the role of covert and overt orienting in generating IOR effects that relate to perception- and action-oriented processes, respectively. Another prominent dissociation concerns the role of covert and overt orienting in generating IOR effects that depend on object- and space-based representation, respectively. Our objective was to evaluate whether these dichotomies are functionally equivalent by manipulating placeholder object presence in the cueing paradigm. By discouraging eye movements throughout, Experiments 1A and 1B validated a perception-oriented form of IOR that depended critically on placeholders. Experiment 2A demonstrated that IOR was robust without placeholders when eye movements went to the cue and back to fixation before the manual response target. In Experiment 2B, we replicated Experiment 2A’s procedures except we discouraged eye movements. IOR was observed, albeit only weakly and significantly diminished relative to when eye movements were involved. We conclude that action-oriented IOR is robust against placeholders but that the magnitude of perception-oriented IOR is critically sensitive to placeholder presence when unwanted oculomotor activity can be ruled out.

A case study approach is applied to review Local Government Authorities (LGA) regional engagement in the Australian context. We address the question 'What are the key LGA enablers/impediments to regional engagement?' by applying Leydesdorff's (2000) proposition that triple helix type network systems exhibit patterns of complex behaviour if the interaction factors that trigger enablers are reflexively declared. The three strands of the LGA triple helix network system are institutions, industry and government. In this case study the LGA's overall management of its regional stakeholder relationships resulted in impediments that limit strong regional engagement. Importantly, the findings inform practitioners, policy-makers and research audiences of the nature of impediments and, by inference, the nature of enablers in LGA triple helix network systems.

Orienting to an uninformative peripheral cue is characterized by a brief facilitation followed by a long-lasting inhibition once attention is removed from the cued location. Although central gaze cues cause reflexive orienting, the inhibitory effect that is relatively ubiquitous following exogenous orienting to uninformative peripheral cues has been relatively rare. We hypothesized that IOR might be seen following gaze-induced orienting if attention were effectively returned to centre by a return gaze or return flash. The time-course of gaze-directed orienting was measured by varying the interval between the gaze cue and a peripheral target requiring an orientation discrimination (permitting measurement of the Simon effect). Significant facilitation was observed at all but the longest SOA tested, 2,880 ms, by which time the facilitation had disappeared with no evidence of IOR. Gaze-induced cuing (which was unaffected by return cue condition) interacted with the Simon effect, decreasing it at the gazed-at location, a pattern that is not seen with more typical endogenous and exogenous cuing. Vision allows for long-distance observation of many important aspects of an organism's environment: Food, predators, and mates. A feature of many visual systems is the ability to orient attention quickly. A shadow looms or blades of grass move, and the organism becomes more alert generally, and shifts its attention to enhance identification of the stimulus and permit appropriate responding as needed. Converging evidence from the Posner cueing paradigm (Posner 1978, 1980), which has become one of the prime tools to study such attentional shifts, and from other paradigms, has led to the conclusion that uninformative peripheral events (cues) can cause rapid automatic orienting of attention (e.g., Jonides, 1981), with targets presented near the stimulated location processed more efficiently than those further away. In a seminal paper, Posner and Cohen (1984) found that this facilitation was confined to short stimulus onset asynchronies (SOAs); at longer ones there is delayed responding to targets presented at the cued location, a phenomenon that was subsequently called inhibition of return (IOR; see Klein, 2000, for a review) by Posner, Rafal, Choate, and Vaughn (1985). Of course, our orienting abilities did not evolve to perform the Posner cuing task. Rather, orienting to food, conspecifics, and predators is important for survival. In social organisms there would likely have been selective pressure to use vision to provide a valuable source of information about what others in our group are attending (e.g., Moore & Dunham, 1995). In this context, it is not surprising then, that when psychologists conducted experiments using uninformative gaze cues presented at fixation, they obtained evidence suggesting that such cues produced relatively rapid automatic orienting in the direction of the gaze (for a review, see Frischen, Bayliss, & Tipper, 2007). The control of orienting by gaze cues was initially explored by developmentalists in infants and toddlers and it has even been observed in nonhuman primates (Tomasella, Call, & Hare, 1998). The developmental work was conducted in the context of "joint visual attention." It is possible that some of the early reports that infants as old as 10 months did not show gaze following (e.g., Corkum & Moore, 1998) were limited by the use of a real actor who may have been too engaging for the children to orient away from (D'Entremont, 2000). In one study, this obstacle was removed by Hood, Willen, and Driver (1998) through the use of a real, but computer-displayed, face whose eyes blinked a few times with forward gaze and unpredictably opened looking leftward or rightward. Shortly thereafter the face disappeared and a target appeared unpredictably on the left or right. Children as young as six months old looked faster when the gaze direction and the location of the object agreed. …

Integral equation (IE) methods may be used to model the interaction between microwave signals and porous materials and hence lead to improvements in time-domain reflectometry (TDR) or other techniques for measurement of moisture content. Although they may employ pulse basis functions to represent the field in each cell of the discretized region, the inherent approximations limit accuracy. Higher order basis functions provide one alternative, but here we describe a method that retains the geometric and cell density advantages of delta functions, and improves accuracy by correcting for the field integration errors of the conventional moment method. Our approach circumvents errors that arise when assuming that the field of a cell is adequately represented by a source at its centre, and results in close agreement between empirical results and the model.

Observers detected targets presented 400 msec after a display containing one cue or two to four cues displayed simultaneously in randomly selected locations on a virtual circle around fixation. The cue arrangement was completely uninformative about the upcoming target's location, and eye position was monitored to ensure that the participants maintained fixation between the cue and their manual detection response. Reflecting inhibition of return (IOR), there was a gradient of performance following single cues, with reaction time decreasing monotonically as the target's angular distance from the cued direction increased. An equivalent gradient of IOR was found following multiple cues whose center of gravity fell outside the parafoveal region and, thus, whose net vector would activate an orienting response. Moreover, on these trials, whether or not the targeted location had been stimulated by a cue had little effect on this gradient. Finally, when the array of cues was balanced so that its center of gravity was at fixation, there was no IOR. These findings, which suggest that IOR is an aftermath of orienting elicited by the cue, are compatible with population coding of the entire cue (as a grouped array for multiple cues) as the generator of IOR.

The water content of baked products such as bread, cake and biscuits, affect the texture, colour, keeping qualities and consumer acceptance. Currently, moisture content is controlled by ensuring a uniform set of ingredients, mixing and baking, but inevitably variation arises from, for example, variation in ingredient characteristics, position within ovens and ambient temperature and relative humidity. A water content sensor that can measure on-line moisture after baking and adjust oven temperature distribution or just the mean oven temperature, will lead to more consistent products. This paper outlines requirements of a sensor for on-line measurement of moisture content, describes a sensor concept that meets these requirements, and then presents the results from experimental work that determined typical permittivity values of bread, one of the target baked products.

The use of time domain reflectometry (TDR) techniques for measuring the moisture content of composite materials is a mature art but usually assumes homogeneity of the material in the transverse plane. As the basis of a forward solution to TDR imaging, we describe an integral equation approach to model the response of the TDR system to a lossless heterogeneous dielectric body. Then, in conjunction with a suitable dielectric model of the composite material, the TDR response to moisture content distribution may be quantified. Several methods for integrating the field values between the transmission line rods were compared and a new method that combines a priori information with linear interpolation provided the most consistent integration for three different permittivity distributions. A self-consistency approach was used to compare the modeled propagation velocity with that expected from transmission line theory.

Lin and Murray published in the 2015 January Issue of Psychological Science a study that claims to have made the surprising discovery of unconscious effects that are stronger than equivalent conscious effects. Specifically, the authors claim to have uncovered dissociable components of aware and unaware orienting and inhibition in exogenous cueing. They suggest an awareness-dependent location-based inhibition mechanism referred to as a negative attentional aftereffect. Here we argue for a simpler explanation, based on established literature, that all they have shown is response inhibition to a consciously perceived cue presented at a fixed location.

When multiple cues are presented simultaneously, Klein, Christie, and Morris (Psychonomic Bulletin & Review 12:295-300, 2005) found a gradient of inhibition (of return, IOR), with the slowest simple manual detection responses occurring to targets in the direction of the center of gravity of the cues. Here, we explored the possibility of extending this finding to the saccade response modality, using methods of data analysis that allowed us to consider the relative contributions of the distance from the target to the center of gravity of the array of cues and the nearest element in the cue array. We discovered that the bulk of the IOR effect with multiple cues, in both the previous and present studies, can be explained by the distance between the target and the center of gravity of the cue array. The present results are consistent with the proposal advanced by Klein et al., (2005) suggesting that this IOR effect is due to population coding in the oculomotor pathways (e.g., the superior colliculus) driving the eye movement system toward the center of gravity of the cued array.

Between 1990 and 1994, Johnston and colleagues (K.J. Hawley, W.A. Johnston, & J.M. Farnham, 1994; W.A. Johnston, K.J. Hawley, J.M. Farnham, 1993; W.A. Johnston, K. J. Hawley, S.H. Plewe, J.M.G. Elliott, & M. J. DeWitt, 1990) published 3 articles on a phenomenon they designated novel popout. The typical interpretation of their findings is that a novel item rapidly and automatically attracts attention when displayed with familiar ones. J. Christie and R. Klein first show that the empirical pattem on which this claim is based can be easily explained in terms of a simple cognitive-load principle and note that effects not subject to this principle (or probability confounds) are rare in the target articles. We then show that these latter effects can be easily'explained without assuming visual orienting toward the novel item. Finally, we outline 2 criteria that must be satisfied in order to make claims about the rapid orienting of attention in arrays with familiar and unfamiliar items, neither of which were met in any of the reviewed experiments.

It has recently been stated that exogenous attention impairs temporal-resolution tasks (Hein, Rolke, & Ulrich, 2006; Rolke, Dinkelbach, Hein, & Ulrich, 2008; Yeshurun, 2004; Yeshurun & Levy, 2003). In comparisons of performance on spatially cued trials versus neutral cued trials, the results have suggested that spatial attention decreases temporal resolution. However, when performance on cued and uncued trials has been compared in order to equate for cue salience, typically speed—accuracy trade-offs (SATs) have been observed, making the interpretation of the results difficult. In the present experiments, we aimed at studying the effect of spatial attention in temporal resolution while using a procedure to control for SATs. We controlled reaction times (RTs) by constraining the time to respond, so that response decisions would be made within comparable time windows. The results revealed that when RT was controlled, performance was impaired for cued trials as compared with neutral trials, replicating previous findings. However, when cued and uncued trials were compared, performance was actually improved for cued trials as compared with uncued trials. These results suggest that SAT effects may have played an important role in the previous studies, because when they were controlled and measured, the results reversed, revealing that exogenous attention does improve performance on temporal-resolution tasks.

Perceptual temporal order judgments require an individual to determine the relative timing of two spatially separate events. Here we reveal the brain regions involved with this task. We had participants observe perceptually identical visual stimuli while conducting two different tasks: discriminating temporal order or discriminating spatial properties. By contrasting the functional magnetic resonance imaging signals during these tasks, we were able to isolate regions specifically engaged by each task. Participants observed two briefly presented rectangles. In one task, participants were instructed to report which appeared first, and, in the other, they were requested to report which rectangle was squarer. A potential confound of this study is that the temporal order judgment (TOJ) task required processing of brief events (onsets), whereas the shape task did not require temporal selectivity. To address this, we conducted a second study in which both tasks required discriminating brief events concurrent with the object onsets. The stimuli were similar to the first experiment, except a gray line was briefly superimposed on each rectangle at onset. Participants reported either which rectangle appeared first (TOJ) or which rectangle had a slightly wider gray line (shape). The first study found that the TOJ task resulted in greater bilateral activation of the temporal parietal junction (TPJ). The second revealed TOJ activation in the TPJ of the left hemisphere. This suggests that TPJ activation increases when we need to temporally sequence information. This finding supports the notion that the TPJ may be a crucial component of the “when” pathway.

The primary cause of failure in glaucoma filtration surgery is fibroblastic proliferation and subconjunctival fibrosis at the bleb site resulting in decreased aqueous flow. We evaluated New Zealand white rabbits in a masked, placebo controlled pilot study to determine the potential reduction of episcleral fibrosis at the surgical bleb site utilizing 0.3 mls of: balanced salt solution (n = 11); an inert gel delivery vehicle (n = 13); the gel delivery vehicle with incorporated recombinant tissue plasminogen activator (tpa; n = 14), 1 mg/ml. Statistical analysis of computer assisted area measurements from multiple histologic sections demonstrated a significant decrease in episcleral fibrosis in the t-PA group as compared to the two other groups (p less than 0.05). Results from the t-PA group did not demonstrate an effect on intraocular pressure. There was no clinical evidence of toxicity or healing complications in the t-PA group.

In highly controlled cuing experiments, conspecific gaze direction has powerful effects on an observer’s attention. We explored the generality of this effect by using paintings in which the gaze direction of a key character had been carefully manipulated. Our observers looked at these paintings in one of three instructional states (neutral, social, or spatial) while we monitored their eye movements. Overt orienting was much less influenced by the critical gaze direction than what the cuing literature might suggest: An analysis of the direction of saccades following the first fixation of the critical gaze showed that observers were weakly biased to orient in the direction of the gaze. Over longer periods of viewing, however, this effect disappeared for all but the social condition. This restriction of gaze as an attentional cue to a social context is consistent with the idea that the evolution of gaze direction detection is rooted in social communication. The picture stimuli from this experiment can be downloaded from the Psychonomic Society’s Archive of Norms, Stimuli, and Data, www.psychonomic.org/archive.

Negative priming from distractors has attracted considerable interest because it appears to reveal a fundamental mechanism of selective attention. Recently, the phenomenon has become muddled because it can be explained in far too many ways. This may partly be because the empirical foundation for the phenomenon has been handicapped by an overreliance on a simplistic comparison of a single experimental condition with control. A sounder approach requires that we collect data that can rule out alternatives to the hypothesis we might favor or test. Regardless of the paradigm used, we propose collecting data from a much fuller set of conditions than is typical. Despite the variety of underlying explanations, we show that the various theories that attribute negative priming to ignoring the distractor predict a common pattern of results across the full set of related conditions. Theories, such as inhibition of return, that do not attribute the cost in performance to ignoring the distractor do not predict this pattern.

Illusory line motion (ILM) has been shown to occur when a line is presented with one end next to a previously stimulated location. The line appears to be drawn away from the site of stimulation. It has been suggested that this is because of the allocation of attention to the stimulated site. Using an endogenous attentional manipulation (a central arrow cue) with no differences in the display between the two ends of the line at the time of line presentation or immediately prior, no ILM was detected, though there was a small effect in the opposite direction. Those who have found endogenously induced ILM have used an endogenous cue based on a property of a location marker that indicated the cued location. Changing the method of cuing to one based on a property of a peripheral marker instead of a central arrow produced a small but significant report of ILM. The small magnitude of the effect, participant self-reports, and the absence of the effect in the purely endogenous condition, suggest that this was merely a bias. ILM is not generated by endogenous attention shifts.

Commissioned by the Bank of Canada to help improve the detection of counterfeit currency, we designed a series of tests of performance to explore the contributions of note quality, sensory modality, training, security features and demographic variables to the accuracy of counterfeit detection with three different note types. In each test, participants (general public, and cash handlers, divided amongst commercial cash handlers and bank tellers) were presented with notes, one at a time, for up to seven seconds, and were asked to judge whether each note was genuine or counterfeit. With whole note inspection, overall accuracy was about 80%. When the security features were tested individually, the Optical Security Device (OSD) was the best feature, the hidden number was the worst, and the portrait, maple leaves, fluorescence, and microprinting were intermediate. Accuracy was higher with notes that could be seen but not touched than vice versa. Cash handlers were 74% correct with touch alone and adding touch to vision significantly improved counterfeit detection. This paper will demonstrate how performance differences between the different note types can be explained in terms of the efficacy of the individual security features incorporated into the notes.

It has been suggested that the difference between misremembering (Orwellian) and misrepresentation (Stalinesque) models of consciousness cannot be differentiated (Dennett, 1991). According to an Orwellian account a briefly presented stimulus is seen and then forgotten, whereas by a Stalinesque account it is never seen. At the same time, Dennett suggested a method for assessing whether an individual is conscious of something. An experiment was conducted which used the suggested method for assessing consciousness to look at Stalinesque and Orwellian distinctions. A visual illusion, illusory line motion, was presented and participants were requested to make judgments that reflected what they were aware of. The participants were able to make responses indicating that they were aware of the actual stimulus in some conditions, but only of the illusion in others. This finding supports a claim that the difference between the Orwellian and Stalinesque accounts may be empirically observable and that both types of events may occur depending on task and stimulus parameters.

The term negative priming has been used to describe the deleterious consequences for performance when the current target shares properties with an ignored distractor from the previous trial. Location-based negative priming was first reported by Tipper, Brehaut, and Driver (1990) who used a prime-probe procedure wherein the task was to localize targets defined by their identity (shape). Design imbalances in this seminal study, and others, are illustrated and it is indicated how these might have contaminated the reported effects. The findings, from three experiments using an unbiased design, suggest that negative priming in the spatial location procedure may be more closely related to inhibition of return (foR), or to the automatic attraction of attention by new objects, than to the concepts of distractor inhibition, episodic retrieval, and feature mismatch, which have traditionally been used to explain negative priming for spatial location. In its most general sense, negative priming is a purely empirically derived concept referring to any negative effect on performance stemming from a previous experience. Since the seminal work of Lowe (1979), Neill (1977), and Tipper (1985), a somewhat narrower construal of this term has dominated the literature. Negative priming in this narrower sense, and as we will use the term here, refers to retarded responding to a target because it shares properties with a distractor from the previous trial (for a review, see Fox, 1995; see Milliken, Joordens, Merikle, & Seiffert, 1998, for a negative priming effect in the more general sense). The proposal that negative priming might reflect cognitive inhibition (Houghton & Tipper, 1994; Klein & Taylor, 1994; Neill, 1977), coupled with the fact that the method for studying its effects involves both memorial and selective processes, has generated numerous studies of negative priming. These studies vary in emphasis from memory to attention and perception, and their participants include children and the aged, as well as individuals suffering from mental disorders like schizophrenia (e.g., Beech, Powell, McWilliam, & Claridge, 1989; Fox, 1994; Hasher, Stoltzfus, Zacks, & Rypma, 1991). In early studies of negative priming, participants made speeded decisions reporting the identity of a target that had been selected, usually in the presence of a distractor, on the basis of its colour or spatial location. Negative priming was observed as delayed responding when the target had the same identity as the immediately preceding distractor. In an influential paper advocating greater ecological validity, Tipper, Brehaut, and Driver (1990) reversed the task: Participants reported the location of a target that was selected on the basis of its identity. On each trial, a target (O) was presented in one of four locations, with or without a distractor (+), and the task was to press a button corresponding to the target's location. Trials were presented in prime/probe pairs, and the critical pairs involved presenting the probe target in the location that had contained a distractor on the prime trial. Tipper et al. reported impaired performance on these critical trials relative to a control condition, for which the probe's items were presented in new locations. This difference was added to a growing list from other procedures thought to reveal negative priming and came to be referred to as "negative priming for spatial location." Partly because of its putative ecological validity, partly because of the simplicity of the task for the participant, and partly because of its ease of implementation (particularly in stripped-down form, see later), the procedure in which participants localize a target on the basis of its identity has become widely used to study negative priming. However, an examination of the literature using this procedure reveals that the typical implementation, which uses a restricted set of the possible prime-probe combinations, introduces biases: Properties of the upcoming probe array are not randomly related to the prime layout which, therefore, might serve as an informative pre-cue. …

Previous work on the object and word superiority effects has demonstrated that activation from stored representations can facilitate identification of items in a visual display. We predicted that activation of this sort might exogenously attract visual attention toward items that have stored representations. To test this prediction, we presented a familiar (word) and an unfamiliar (nonword) item simultaneously at unpredictable locations, and after varying delays, moved one of the stimuli. In accord with our prediction, at the shortest intervals subjects were more efficient at discriminating motion of the familiar item. Control data demonstrated that this advantage was due to a competitive interaction and not to the familiarity of the items per se.

The spatial contiguity between Pavlovian conditioned and unconditioned stimuli was examined using a chamber designed to prevent the usual confounding with delay of reinforcement. Eight ring doves were autoshaped in this apparatus. For half of the trials, a conditioned stimulus (CS) was presented 11 cm from the unconditioned stimulus (US); for the other trials, another CS was presented 74 cm away. After extended training, the stimuli were presented in nonreinforced test trials at a common, intermediate (42 cm) position. The CS that had been nearer the US was approached more closely, indicating that higher spatial contiguity facilitates Pavlovian conditioning. This research was funded by a grant from the National Science and Engineering Research Council to B. R. Moore, who also assisted in designing the apparatus. Thanks are extended to Tracy Taylor, Billy Schmidt, and B. R. Moore for suffering through drafts of this manuscript and providing helpful insights to improve the writing. Thanks are also extended to Bob Barnet for help in clarifying this paper and inspiring some of the ideas for future research.

The authors have designed a computer-based health education programme introducing coronary heart disease (CHD) prevention to primary school children using the novel authoring system, Course Builder. To aid design of the programme, the basic knowledge of a randomly selected group of 90 children aged 8-11 years old from three city schools was assessed, using a questionnaire in storyline format. This surveyed children's understanding of the heart's basic function, the importance and prevalence of CHD, and perception of CHD as a preventable disease. The children's response after using the programme and their increased knowledge and awareness were evaluated, and the programme was deemed an overwhelming success.

This paper contributes to a new area of research, namely: institutional preparedness of economic development agencies for developing small and medium-sized enterprises (SMEs). The cases presented illustrate variations in the micro-finance lender agency-enterprise development of processes for sharing vision and interdependence. In clarifying the nature of the agency-enterprise relationship along these two dimensions, we develop a set of propositions. Our model contends: 1) that effective processes for sharing vision and good cooperation maximise the likelihood of explication of tacit knowledge; 2) that ineffective processes for sharing vision and good cooperation lead to ad hoc explication of tacit knowledge; 3) ineffective processes for sharing vision and poor cooperation minimise the likelihood of explication of tacit knowledge; 4) effective processes for sharing vision and poor cooperation maximise the likelihood of explication of tacit knowledge.