Emotions, personality, and health: introduction to the special issue

Our intent in this introduction to the special issue on Emotions, Personality, and Health is to alert readers to the logic underlying the editors' choices of topics for the issue and to provide a brief summary of its contents. We discuss how the 10 articles fit together to provide a mosaic of diverse approaches to the study of emotion. Collectively, these articles show ways that emotion research may be integrated with personality theory to inform us about the psychological dimensions of health and illness.     

Selection of tool diameter by New Caledonian crows<Emphasis Type="Italic"> Corvus moneduloides</Emphasis>

One important element of complex and flexible tool use, particularly where tool manufacture is involved, is the ability to select or manufacture appropriate tools anticipating the needs of any given task—an ability that has been rarely tested in non-primates. We examine aspects of this ability in New Caledonian crows—a species known to be extraordinary tool users and manufacturers. In a 2002 study, Chappell and Kacelnik showed that these crows were able to select a tool of the appropriate length for a task among a set of different lengths, and in 2002, Weir, Chappell and Kacelnik showed that New Caledonian crows were able to shape unfamiliar materials to create a usable tool for a specific task. Here we examine their handling of tool diameter. In experiment 1, we show that when facing three loose sticks that were usable as tools, they preferred the thinnest one. When the three sticks were presented so that one was loose and the other two in a bundle, they only disassembled the bundle when their preferred tool was tied. In experiment 2, we show that they manufacture, and modify during use, a tool of a suitable diameter from a tree branch, according to the diameter of the hole through which the tool will have to be inserted. These results add to the developing picture of New Caledonian crows as sophisticated tool users and manufacturers, having an advanced level of folk physics.Electronic Supplementary Material Supplementary material is available in the online version of this article at     

Color realism and color science

The target article is an attempt to make some progress on the problem of color realism. Are objects colored? And what is the nature of the color properties? We defend the view that physical objects (for instance, tomatoes, radishes, and rubies) are colored, and that colors are physical properties, specifically, types of reflectance. This is probably a minority opinion, at least among color scientists. Textbooks frequently claim that physical objects are not colored, and that the colors are "subjective" or "in the mind." The article has two other purposes: First, to introduce an interdisciplinary audience to some distinctively philosophical tools that are useful in tackling the problem of color realism and, second, to clarify the various positions and central arguments in the debate. The first part explains the problem of color realism and makes some useful distinctions. These distinctions are then used to expose various confusions that often prevent people from seeing that the issues are genuine and difficult, and that the problem of color realism ought to be of interest to anyone working in the field of color science. The second part explains the various leading answers to the problem of color realism, and (briefly) argues that all views other than our own have serious difficulties or are unmotivated. The third part explains and motivates our own view, that colors are types of reflectances and defends it against objections made in the recent literature that are often taken as fatal.     

In the privacy of their own homes: using the internet to assess racial bias

Recent studies suggest that research participants show reduced distortion of their taboo attitudes and behaviors when they take part in Internet-based procedures from outside the laboratory. We explored whether such procedures would reduce distortion in the assessment of racial bias. In Study 1, White participants who completed the study in the laboratory evaluated Black targets more favorably than White targets. This unexpected "outgroup-favoring" pattern occurred in both pencil-and-paper and Internet versions of the study, showing that modality did not produce it; but when participants worked outside the laboratory via the Internet, this pattern disappeared. Study 2 replicated the above findings and further indicated that the reduced distortion in Internet-based studies was due to the removal of the experimenter rather than removing the participants from the laboratory environment. The implications of these findings for the study of controlled processes of prejudice and the nature of Internet-based social communication are discussed.     

Statistical inference in behavior analysis: Friend or foe?

Behavior analysts are undecided about the proper role to be played by inferential statistics in behavioral research. The traditional view, as expressed in Sidman's Tactics of Scientific Research (1960), was that inferential statistics has no place within a science that focuses on the steady-state behavior of individual organisms. Despite this admonition, there have been steady inroads of statistical techniques into behavior analysis since then, as evidenced by publications in the Journal of the Experimental Analysis of Behavior. The issues raised by these developments were considered at a panel held at the 24th annual convention of the Association for Behavior Analysis, Orlando, Florida (May, 1998). The proceedings are reported in this and the following articles.     

Formula: see text]Executive functions in extremely low birth weight and late-preterm preschoolers: Effects on working memory and response inhibition

Executive function (EF) refers to fundamental capacities that underlie more complex cognition and have ecological relevance across the individual's lifespan. However, emerging executive functions have rarely been studied in young preterm children (age 3) whose critical final stages of fetal development are interrupted by their early birth. We administered four novel touch-screen computerized measures of working memory and inhibition to 369 participants born between 2004 and 2006 (52 Extremely Low Birth Weight [ELBW]; 196 late preterm; 121 term-born). ELBW performed worse than term-born on simple and complex working memory and inhibition tasks and had the highest percentage of incomplete performance on a continuous performance test. The latter finding indicates developmental immaturity and the ELBW group's most at-risk preterm status. Additionally, late-preterm participants performed worse compared with term-born on measures of complex working memory but did not differ from those term-born on response inhibition measures. These results are consistent with a recent literature that identifies often subtle but detectable neurocognitive deficits in late-preterm children. Our results support the development and standardization of computerized touch-screen measures to assess EF subcomponent abilities during the formative preschool period. Such measures may be useful to monitor the developmental trajectory of critical executive function abilities in preterm children, and their use is necessary for timely recognition of deficit and application of appropriate interventional strategies.     

Approaching stimuli bias attention in numerical space

Increasing evidence suggests that common mechanisms underlie the direction of attention in physical space and numerical space, along the mental number line. The small leftward bias (pseudoneglect) found on paper-and-pencil line bisection is also observed when participants 'bisect' number pairs, estimating (without calculating) the number midway between two others. Here we investigated the effect of stimulus motion on attention in numerical space. A two-frame apparent motion paradigm manipulating stimulus size was used to produce the impression that pairs of numbers were approaching (size increase from first to second frame), receding (size decrease), or not moving (no size change). The magnitude of pseudoneglect increased for approaching numbers, even when the final stimulus size was held constant. This result is consistent with previous findings that pseudoneglect in numerical space (as in physical space) increases as stimuli are brought closer to the participant. It also suggests that the perception of stimulus motion modulates attention over the mental number line and provides further support for a connection between the neural representations of physical space and number.