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It is debated whether subregions within the medial temporal lobe (MTL), in particular the hippocampus (HC) and perirhinal cortex (PrC), play domain-sensitive roles in learning. In the present study, two patients with differing degrees of MTL damage were first exposed to pairs of highly similar scenes, faces, and dot patterns and then asked to make repeated same/different decisions to preexposed and nonexposed (novel) pairs from the three categories (Experiment 1). We measured whether patients would show a benefit of prior exposure (preexposed > nonexposed) and whether repetition of nonexposed (and preexposed) pairs at test would benefit discrimination accuracy. Although selective HC damage impaired learning of scenes, but not faces and dot patterns, broader MTL damage involving the HC and PrC compromised discrimination learning of scenes and faces but left dot pattern learning unaffected. In Experiment 2, a similar task was run in healthy young participants in the MRI scanner. Functional region-of-interest analyses revealed that posterior HC and posterior parahippocampal gyrus showed greater activity during scene pattern learning, but not face and dot pattern learning, whereas PrC, anterior HC, and posterior fusiform gyrus were recruited during discrimination learning for faces, but not scenes and dot pattern learning. Critically, activity in posterior HC and PrC, but not the other functional region-of-interest analyses, was modulated by accuracy (correct > incorrect within a preferred category). Therefore, both approaches revealed a key role for the HC and PrC in discrimination learning, which is consistent with representational accounts in which subregions in these MTL structures store complex spatial and object representations, respectively. [ABSTRACT FROM AUTHOR]

People are extremely efficient at detecting relevant objects in complex natural scenes. In three experiments, we used functional magnetic resonance imaging-guided transcranial magnetic stimulation (TMS) to investigate the role of the extrastriate body area (EBA) in the detection of people in scenes. In Experiment 1, participants reported, in different blocks, whether people or cars were present in a briefly presented scene. Detection (D-prime) of people, but not of cars, was impaired after TMS over right EBA (rEBA; five pulses at -- 200, --100, 0,100,200 ms) compared with sham stimulation. In Experiment 2, we applied TMS either before ( -- 200, --100 ms) or after ( +100, + 200) the scene onset. Poststimulus EBA stimulation impaired people detection relative to prestimulus EBA stimulation, while timing had no effect during sham stimulation. In Experiment 3, we examined anatomical specificity by comparing TMS over EBA with TMS over scene-selective transverse occipital sulcus (TOS). Two scenes were presented side by side, and response times to detect which scene contained people (or cars) were measured. For people detection, but not for car detection, response times during EBA stimulation were significantly slower than during TOS stimulation. Furthermore, rEBA stimulation led to an equivalent slowing of response times to left and right lateralized targets. These findings are the first to demonstrate the causal involvement of a category-selective human brain region in detecting its preferred stimulus category in natural scenes. They shed light on the nature of such regions, and help us understand how we efficiently extract socially relevant information from a complex input. [ABSTRACT FROM AUTHOR]

Investigates the cortical area selective for visual processing of the human body. Details on the functional magnetic resonance imaging studies; Distinction on the cortical region in human; Range of control stimuli.

Presents a study using functional magnetic resonance imaging (fMRI) to test key predictions of the object-based theory, which proposes that pre-attentive mechanisms segment the visual array into discrete objects, groups, or surfaces, which serve as targets of visual attention. Method; Implications.

Presents a study on line-motion illusion. Information on studies on visual attention; Explanation of the method used to carry out the study; Results of the study.

Replies to authors B.W.A. Whittlesea, M.D. Dorken and K.W. Podrouzek's argument against the type-token account of repetition blindness. General and pervasive confusion in Whittlesea and colleagues' arguments; Difficulties in a repetition-detection task; Postlist effects on performance according to an article written by Whittlesea and Podrouzek.

A simulation model of enforcement of the federal new source fly ash standard for coal-fired power plants indicates the standard is likely to be frequently violated. This is partly due to a pollution control device certification test which allows the average of as few as three tests to be used as an indicator of compliance. In accordance with the central limit theorem, this can lead to selection of inadequate control devices. Enforcement systems must account for the stochastic properties of pollution control devices and the implications of certification test sampling procedures for firm behavior if effective enforcement is to be achieved. [ABSTRACT FROM AUTHOR]

Self-limiting growth policies are waxing strong in the suburbs. The sewer moratorium in Fairfax County, Virginia, and the building permit limitation in Petaluma, California, are two well-known examples. The present residents of these areas view growth as bad, apparently because it destroys the amenities for which they chose the area. Potential new residents seek to locate in these communities to obtain these amenities and view the exclusion attempts as unfair. Underlying these contentions is the implied issue of the fiscal impact of growth. The question is not new, and the policies employed by most suburbs are not substantially different from those employed in the 1960s. Rather, it is the explicit stating of the nongrowth or limited growth goal which is new. The purpose of this article is to explore the reasons for the nongrowth movement, analyze the economic and political components of existing attempts at growth control, and suggest some policy alternatives which may lead to an efficient and politically acceptable solution to the problems associated with the growth decision.

Simulation analysis is used to investigate enforcement of the new source performance standard for particulate matter discharges from coal-fired power plants. The analysis uses engineering and econometric estimates of relevant cost and performance paramenters. Results are generalized by Monte Carlo selection over distributions of each of the appropriate parameter values. The simulations are summarized through recession analysis on the outcomes. Under current legal enforcement it is found that most power plants will violate the standard, that small plants will control to higher removal levels than large plants and that power companies will install relatively costly pollution control technology. Three enforcement alternatives are considered for overcoming these shortcomings: more stringent legal enforcement, enforcement using emission taxes, and a mixed system which uses device certification tests and emission taxes. It is found that each of the alternatives can lead to the standard being met and to more-or-less equal sharing in control burden across plant size. But it is only the two systems which use emission taxes that give incentive for choosing least costly control technology. It is also suggested that emission tax systems are likely to provide stronger incentives toward early compliance. The general applicability of these conclusions to other enforcement situations is discussed. [ABSTRACT FROM AUTHOR]

Develops the theoretical reasons why user charge finance leads to improved government efficiency and reduced expenditures. Details on the bureaucracy theory of William Niskanen; Important relationship of user charge to efficiency in the public sector; Discussion on the theory of user charge finance; Bureaucratic response to user charges; Conclusion.

The purpose of this article is to present a summary of the difficulties encountered in implementing the existing regulatory approach and to use this information to suggest the difficulties which are likely to be encountered in implementing any practical incentive based system. To accomplish this task, a general model of regulatory enforcement is described and interpreted in terms of current practice in implementation and enforcement. Turning attention to practical economic incentive systems, it is pointed out that most of the same policy issues must be resolved.

The article provides information on cross-national comparisons in environmental protection. In comparing the institutional structure of pollution control in various countries, one finds some universal truths. A federal/regional/local jurisdictional split is universal. Although the degree of emphasis or authority differs from case to case, one observes that local authorities, or at least regional (state) authorities, have the closest contact with sources to be controlled and that federal authorities have limited control over the actions of lower level jurisdictions.

The enforcement of pollution control laws is an important component of the implementation process. Much has been written about the implementation of pollution control laws in the U.S. but there has been relatively little attention to the issues of enforcement. In this paper, the existing literature on enforcement of pollution laws, supplement it with a case study of water pollution control equipment, and interpret the findings in terms of the economics faced by the firm and the control agency, is stated.

This article presents a study, which examines factors affecting commercial land values. Land rent and hence land value can be defined as the excess of total revenue aver the total. costs of production at that site. This excess is the result of the natural productivity of the site and tile activities of man which alter the site's productivity. Man alters the natural conditions of urban land by building improvements on it, supplying it with public services such as water, sewer and roads, arid altering the productivity of the sites surrounding it. Several writers have statistically explored the importance of various actors in determining urban land value. Many urban land value models have been presented in the literature. Many of these have their main emphasis on one aspect or another of location or transportation costs. These models often include consideration of lot size as well. Several studies have added other variables to location and lot size such as amenities, social overhead capital, taxes, topography, land use, and zoning.

This article discusses the extension of sewer service at the urban-rural fringe. Society is now demanding that the quality of the environment be maintained and perhaps improve. The concentration of people and the gaps in urban development which are characteristic of urban expansion combine to increase the problems associated with the disposal of human wastes. This paper discusses the economics of extending the community sewage disposal system into areas which are now commonly served by septic tanks. The costs of the two alternatives under various assumptions are determined. Then a comparison of these costs is made in two cases. The first case is that of a subdivision adjacent to an area already being served by the community system. The second case is that of a sub-division not immediately adjacent to the edge of community sewer service. In order to treat sewage, it is necessary to transport it through a sewer from the site of production to the treatment plant. The two most important factors affecting sewer costs are density and distance.

Abstract: We offer a critique of Ishai''s [Ishai, A., 2008. Let''s face it: it''s a cortical network. NeuroImage. doi:10.1016/j.neuroimage.2007.10.040] comment on the value of considering the brain areas that support face perception as a network. We emphasise that this idea is not in opposition to the notion that the fusiform gyrus plays a key role in the visual analysis of faces. More important, we argue that the definition offered of the “extended” face network – areas showing a greater fMRI response to intact than scrambled face images – is too inclusive, and present data to indicate that at least two of the proposed “nodes” of this network also respond to non-face objects (compared to scrambled controls). Finally, we consider briefly how converging methodological approaches may augment the use of fMRI alone in understanding how anatomically widespread brain areas coordinate their activity in order to make sense of the human face. [Copyright &y& Elsevier]

We efficiently infer others' states and traits from their appearance, and these inferences powerfully shape our social behaviour. One key trait is sex, which is strongly cued by the appearance of the body. What are the visual representations that link body shape to sex? Previous studies of visual sex judgment tasks find observers have a bias to report "male", particularly for ambiguous stimuli. This finding implies a representational asymmetry - that for the processes that generate a sex percept, the default output is "male", and "female" is determined by the presence of additional perceptual evidence. That is, female body shapes are positively coded by reference to a male default shape. This perspective makes a novel prediction in line with Treisman's studies of visual search asymmetries: female body targets should be more readily detected amongst male distractors than vice versa. Across 10 experiments (N = 32 each) we confirmed this prediction and ruled out alternative low-level explanations. The asymmetry was found with profile and frontal body silhouettes, frontal photographs, and schematised icons. Low-level confounds were controlled by balancing silhouette images for size and homogeneity, and by matching physical properties of photographs. The female advantage was nulled for inverted icons, but intact for inverted photographs, suggesting reliance on distinct cues to sex for different body depictions. Together, these findings demonstrate a principle of the perceptual coding that links bodily appearance with a significant social trait: the female body shape is coded as an extension of a male default. We conclude by offering a visual experience account of how these asymmetric representations arise in the first place. [ABSTRACT FROM AUTHOR]

Expectations about a visual event shape the way it is perceived [ 1–4 ]. For example, expectations induced by valid cues signaling aspects of a visual target can improve judgments about that target, relative to invalid cues [ 5, 6 ]. Such expectation effects are thought to arise via pre-activation of a template in neural populations that represent the target [ 7, 8 ] in early sensory areas [ 9 ] or in higher-level regions. For example, category cues ("face" or "house") modulate pre-target fMRI activity in associated category-selective brain regions [ 10, 11 ]. Further, a relationship is sometimes found between the strength of template activity and success in perceptual tasks on the target [ 12–14 ]. However, causal evidence linking pre-target activity with expectation effects is lacking. Here we provide such evidence, using fMRI-guided online transcranial magnetic stimulation (TMS). In two experiments, human volunteers made binary judgments about images of either a body or a scene. Before each target image, a verbal cue validly or invalidly indicated a property of the image, thus creating perceptual expectations about it. To disrupt these expectations, we stimulated category - selective visual brain regions (extrastriate body area, EBA; occipital place area, OPA) during the presentation of the cue. Stimulation ended before the target images appeared. We found a double dissociation: TMS to EBA during the cue period removed validity effects only in the body task, whereas stimulating OPA removed validity effects only in the scene task. Perceptual expectations are expressed by the selective activation of relevant populations within brain regions that encode the target. • Expectations influence perception of visual events • Anticipatory activity in category-specific regions expresses expectations • Disruption of this activity removes effects of cues on discrimination performance Gandolfo and Downing demonstrate that perceptual expectations about an upcoming visual stimulus are expressed in the brain activity of category-selective brain regions: online transcranial magnetic brain stimulation over such regions selectively removes the behavioral effects of predictive verbal pre-cues on perceptual discrimination tasks. [ABSTRACT FROM AUTHOR]

Summary: A new study using transcranial magnetic stimulation of the brain shows that each of three neighboring areas of visual cortex plays a specific and causal role in perceiving faces, bodies and other kinds of objects. [Copyright &y& Elsevier]

The article cites the sky observations of the three British Astronomical Association members, Paul Downing, Tony Angel and Karen Holland, in the Alpujarras Region of the Sierra Nevada mountains in Spain during dark skies. During the observation initiatives and with the use of telescopes, Downing and Angels had observed images of comet locations and motions. It informs that Downing had used Observatorio de la Divisa as his sight of study, while Angels used Observatorio de la Contraviesa.

Functional neuroimaging research has shown that certain classes of visual stimulus selectively activate focal regions of visual cortex. Specifically, cortical areas that generally and selectively respond to faces (Kanwisher, N., McDermott, J., & Chun, M. M. (1997). The fusiform face area: a module in human extrastriate cortex specialized for face perception. Journal of Neuroscience, 17(11), 4302–4311; Puce, A., Allison, T., Asgari, M., Gore, J. C., & McCarthy, G. (1996). Differential sensitivity of human visual cortex to faces, letterstrings, and textures: a functional magnetic resonance imaging study. Journal of Neuroscience, 16(16), 5205–5215.) and to the human body (Downing, P. E., Jiang, Y., Shuman, M., & Kanwisher, N. (2001). A cortical area selective for visual processing of the human body. Science, 293(5539), 2470–2473.) have recently been described using fMRI. A parallel body of research has focused on the ability of faces to “capture” the focus of attention, compared to other kinds of objects (Lavie, N., Ro, T., & Russell, C. (2003). The role of perceptual load in processing distractor faces. Psychological Science, 14(5), 510–515; Ro, T., Russell, C., & Lavie, N. (2001). Changing faces: a detection advantage in the flicker paradigm. Psychological Science, 12(1), 94–99; Vuilleumier, P. (2000). Faces call for attention: evidence from patients with visual extinction. Neuropsychologia, 38(5), 693–700.). The present study uses Mack and Rock''s “inattentional blindness” paradigm to investigate whether unexpected, task-irrelevant human body stimuli capture awareness when attention is occupied by a primary task (Mack, A., & Rock, I. (1998). Inattentional blindness. London: MIT Press). Silhouettes and stick figures of human bodies, and silhouettes of hands, were compared to control stimuli including object silhouettes, object stick figures, and scrambled silhouettes of bodies, body parts, and objects. Participants were significantly better able to detect a human figure relative to the control stimuli. These results suggest that the human body, like the face, may be prioritized for attentional selection. More generally, they are consistent with the proposal that the visual system assigns attentional priority to types of stimuli that are also represented in strongly selective cortical regions. [Copyright &y& Elsevier]

The relationship between working memory and selective attention has traditionally been discussed as operating in one direction: Attention filters incoming information, allowing only relevant information into short-term processing stores. This study tested the prediction that the contents of visual working memory also influence the guidance of selective attention. Participants held a sample object in working memory on each trial. Two objects, one matching the sample and the other novel, were then presented simultaneously. As measured by a probe task, attention shifted to the object matching the sample. This effect generalized across object type, attentional-probe task, and working memory task. In contrast, a matched task with no memory requirement showed the opposite pattern, demonstrating that this effect is not simply due to exposure to the sample. These results confirm a specific prediction about the influence of working memory contents on the guidance of attention. [ABSTRACT FROM AUTHOR]