Is the Brain a Quantum Computer?

We argue that computation via quantum mechanical processes is irrelevant to explaining how brains produce thought, contrary to the ongoing speculations of many theorists. First, quantum effects do not have the temporal properties required for neural information processing. Second, there are substantial physical obstacles to any organic instantiation of quantum computation. Third, there is no psychological evidence that such mental phenomena as consciousness and mathematical thinking require explanation via quantum theory. We conclude that understanding brain function is unlikely to require quantum computation or similar mechanisms.     

The classification of violence risk

The Classification of Violence Risk (COVR) is an interactive software program designed to estimate the risk that a person hospitalized for mental disorder will be violent to others. The software leads the evaluator through a chart review and a brief interview with the patient. At the end of this interview, the software generates a report that contains a statistically valid estimate of the patient's violence risk-ranging from a 1% to a 76% likelihood of violence-including the confidence interval for that estimate, and a list of the risk factors that the program took into account to produce the estimate. In this article, the development of the COVR software is described and several issues that arise in its administration are discussed.     

Unit bias. A new heuristic that helps explain the effect of portion size on food intake

ABSTRACT— People seem to think that a unit of some entity (with certain constraints) is the appropriate and optimal amount. We refer to this heuristic as unit bias. We illustrate unit bias by demonstrating large effects of unit segmentation, a form of portion control, on food intake. Thus, people choose, and presumably eat, much greater weights of Tootsie Rolls and pretzels when offered a large as opposed to a small unit size (and given the option of taking as many units as they choose at no monetary cost). Additionally, they consume substantially more M&M's when the candies are offered with a large as opposed to a small spoon (again with no limits as to the number of spoonfuls to be taken). We propose that unit bias explains why small portion sizes are effective in controlling consumption; in some cases, people served small portions would simply eat additional portions if it were not for unit bias. We argue that unit bias is a general feature in human choice and discuss possible origins of this bias, including consumption norms.     

Looking deathworthy: perceived stereotypicality of Black defendants predicts capital-sentencing outcomes

Researchers previously have investigated the role of race in capital sentencing, and in particular, whether the race of the defendant or victim influences the likelihood of a death sentence. In the present study, we examined whether the likelihood of being sentenced to death is influenced by the degree to which a Black defendant is perceived to have a stereotypically Black appearance. Controlling for a wide array of factors, we found that in cases involving a White victim, the more stereotypically Black a defendant is perceived to be, the more likely that person is to be sentenced to death.     

Enhancing the transfer of computer-assisted training proficiency in geographically distributed teams

The authors examined factors that determine whether knowledge gained from computer-assisted (i.e., technology-based) team training in a geographically distributed team (GDT) context transfers to organizational results. They examined the moderating effects of team trust, technology support, and leader experience on the relation between teams' average individual training proficiency on a computer-assisted (i.e., CD-ROM-based) training program and team performance as assessed by team customer satisfaction ratings. Using data collected from 40 GDTs in a high-technology company, the authors found that the relation between teams' average training proficiency and team performance was complex and moderated by several factors. In particular, teams' average training proficiency had a positive association with customer satisfaction when GDTs were higher, rather than lower, in both trust and technology support and when team leaders had longer, rather than shorter, levels of tenure with their specific team.     

Adult age, gender, and race group differences in images of aging

Younger and older African American and Caucasian American adults, who were matched by age (M age = 40.63 years), completed a survey on perceptions of aging and subjective age. The 2 groups did not differ in the age they considered someone to be old (M age = 74.5 years). However, when asked which age was the happiest age, African Americans chose a significantly younger age (M age = 18.26 years) than did Caucasian Americans (M age = 31.32 years), and this racial group difference interacted with age differences such that older Caucasian Americans named an older age than did younger Caucasian Americans. The authors found no such age difference for African Americans. When asked if old age was a happy time, 60% of Caucasian Americans answered yes, whereas only 2% of African Americans answered yes. These and other differences in images and concerns of old age and subjective age suggest a far more negative view of aging for African Americans and a need for changes in the provision of positive information about aging for this group.     

Predicting travel attitudes among university faculty after 9/11

The authors interviewed a random sample of 306 university faculty as part of an annual university poll. Items focused on air travel concerns following 9/11, positive aspects of travel, and future travel intentions. Demographic factors were not significant predictors for men or women faculty. Faculty expressed positive attitudes toward travel, for example agreeing that travel allows them to demonstrate competency. Concerns about missing connections and delays elicited a larger percent of negative reactions than concerns about hijackings or security. Gender differences were not observed on individual items, but in regression analyses a composite of self-reported travel risk factors was more predictive of future travel plans for women than for men, although women expected to travel as much in the future as men. The results are consistent with positive psychology and speak to applied aspects of travel and tourism.     

Fragments of the Roelofs effect: a bottom-up effect equal to the sum of its parts

The Roelofs effect is a distortion of perceived space that occurs when a large frame whose center is offset left or right from the objective midline is presented visually to an observer and causes a bias in the observer's subjective judgment of midline. Experiments were designed to test whether an isolated fragment (left or right end) of a Roelofs-inducing frame was capable of generating the Roelofs effect and to determine whether prior experience with intact frames would provide a top-down influence that would bias the Roelofs effect resulting from fragment presentation. Although the fragments did induce an effect, top-down information did not play a significant role even after a 5-day training paradigm. Instead, we found that the effect generated by an intact frame was equal in magnitude to the sum of the effects generated by the individual fragments. In addition, perception was found to be differentially affected by the two ends of the frame, with fragments falling in the right visual field causing a larger effect than those falling in the left.     

Connectivity among semantic associates: an fMRI study of semantic priming

Semantic priming refers to a reduction in the reaction time to identify or make a judgment about a stimulus that has been immediately preceded by a semantically related word or picture and is thought to result from a partial overlap in the semantic associates of the two words. A semantic priming lexical decision task using spoken words was presented in event-related fMRI and behavioral paradigms. Word pairs varied in terms of semantic relatedness and the connectivity between associates. Thirteen right-handed subjects underwent fMRI imaging and 10 additional subjects were tested in a behavioral version of the semantic priming task. It was hypothesized priming would be greatest, reaction time fastest, and cortical activation reduced the most for related word pairs of high connectivity, followed by related word pairs of low connectivity, and then by unrelated word pairs. Behavioral and fMRI results confirmed these predictions. fMRI activity located primarily in bilateral posterior superior and middle temporal regions showed modulation by connectivity and relatedness. The results suggest that these regions are involved in semantic processing.     

Processing Unpointed Hebrew: What Can We Learn from Determining the Identicalness of Monosyllabic and Bisyllabic Nouns

The aim of this study was to determine whether Hebrew readers reference phonological information for the silent processing of unpointed Hebrew nouns. A research paradigm in which participants were required to perform consecutive same/different judgments regarding the identicalness of members of stimulus pairs was used for answering this question. Twenty-eight students (mean grade 4.9) participated in the study. The nouns used in preparing the word stimulus pairs were comprised of various amounts of syllabic information (monosyllabic versus bisyllabic) and differed in the degree this information was represented by their letter graphemes. The main findings suggest that the processing of the identicalness of unpointed Hebrew words may not involve the referencing of their phonological information.