Working memory and working attention: What could possibly evolve?

The concept of “working” memory is traceable back to nineteenth century theorists (Baldwin, 1894; James 1890) but the term itself was not used until the mid-twentieth century (Miller, Galanter & Pribram, 1960). A variety of different explanatory constructs have since evolved which all make use of the working memory label (Miyake & Shah, 1999). This history is briefly reviewed and alternative formulations of working memory (as language-processor, executive attention, and global workspace) are considered as potential mechanisms for cognitive change within and between individuals and between species. A means, derived from the literature on human problem-solving (Newell & Simon, 1972), of tracing memory and computational demands across a single task is described and applied to two specific examples of tool-use by chimpanzees and early hominids. The examples show how specific proposals for necessary and/or sufficient computational and memory requirements can be more rigorously assessed on a task by task basis. General difficulties in connecting cognitive theories (arising from the observed capabilities of individuals deprived of material support) with archaeological data (primarily remnants of material culture) are discussed

Earworms ("stuck song syndrome"): towards a natural history of intrusive thoughts

Two studies examine the experience of “earworms”, unwanted catchy tunes that repeat. Survey data show that the experience is widespread but earworms are not generally considered problematic, although those who consider music to be important to them report earworms as longer, and harder to control, than those who consider music as less important. The tunes which produce these experiences vary considerably between individuals but are always familiar to those who experience them. A diary study confirms these findings and also indicates that, although earworm recurrence is relatively uncommon and unlikely to persist for longer than 24 hours, the length of both the earworm and the earworm experience frequently exceed standard estimates of auditory memory capacity. Active attempts to block or eliminate the earworm are less successful than passive acceptance, consistent with Wegner’s (1994) theory of ironic mental control

Reusable high-temperature heat pipes and heat pipe panels

A reusable, durable heat pipe which is capable of operating at temperatures up to about 3000 F in an oxidizing environment and at temperatures above 3000 F in an inert or vacuum environment is produced by embedding a refractory metal pipe within a carbon-carbon composite structure. A reusable, durable heat pipe panel is made from an array of refractory-metal pipes spaced from each other. The reusable, durable, heat-pipe is employed to fabricate a hypersonic vehicle leading edge and nose cap

Using financial incentives to encourage welfare recipients to become economically self-sufficient

Public welfare ; Poverty ; Employment (Economic theory)

Less-is-more effects without the recognition heuristic

Inferences consistent with “recognition-based” decision-making may be drawn for various reasons other than recognition alone. We demonstrate that, for 2-alternative forced-choice decision tasks, less-is-more effects (reduced performance with additional learning) are not restricted to recognition-based inference but can also be seen in circumstances where inference is knowledge-based but item knowledge is limited. One reason why such effects may not be observed more widely is the dependence of the effect on specific values for the validity of recognition and knowledge cues. We show that both recognition and knowledge validity may vary as a function of the number of items recognized. The implications of these findings for the special nature of recognition information, and for the investigation of recognition-based inference, are discusse

The Demand for Lottery Products

Lotteries constitute one of the fastest-growing categories of consumer expenditure in the United States. Not only have an increasing number of states legalized state lotteries, but the per capita expenditures on lotteries in lottery states have increased at an annual rate of 13 percent after inflation between 1975 and 1988. This article examines the demand for lottery products. A majority of the adult public in lottery states play in any one year, but relatively few of these players account for most of the action". Socioeconomic patterns of play, measured from both sales data and household surveys, offer some surprises -- for example, that the Engle curve of lottery expenditures decline with income. There is some evidence that lottery sales increase with the payout rate, although it is not clear that it would be profitable for the states to increase payout rates. The addition of a new game, such as lotto, does not undercut sales of existing games, and the oft-heard claim that interest (and sales) will "inevitably" decline is contradicted by the data. The organizational form of the lottery is evolving in response to the quest for higher revenues: in particular, smaller states are forming multistate game. This article is a chapter from Selling Hope: State Lotteries in America, an NBER monograph to be published by Harvard University Press in November, 1989.

THE IMPACTS OF DAIRY CATTLE OWNERSHIP ON THE NUTRITIONAL STATUS OF PRE-SCHOOL CHILDREN IN COASTAL KENYA

Anthropometric measurements for children and household characteristics were collected form 198 households in coastal Kenya to examine the impacts of dairy technology adoption on nutritional status. Random effects models indicate that dairy technology adoption positively influences chronic malnutrition, but that dairy consumption has a larger impact than adoption per se.Food Consumption/Nutrition/Food Safety, Livestock Production/Industries,

Determining factors of clinical outcomes in paediatric intussusception at Johannesburg hospital

A research report submitted to the Faculty of Health Sciences, University of the Witwatersrand, in partial fulfilment for the degree Master of Medicine (Surgery)Aim: The aim of this research report is to assess which local epidemiological and clinical factors determine impact on the morbidity and mortality of intussusception, expressed as defined clinical outcomes. Methods: A retrospective hospital record review of paediatric intussusception admitted to Chris Hani Baragwanath (CHBH) and Charlotte Maxeke Johannesburg Academic Hospitals (CMJAH) for the period of January 2007 to April 2010 was undertaken. The four determining factors evaluated are: Duration of symptoms, weight, palpable rectal intussusceptum, admission serum C-­‐reactive protein, against seven possible clinical outcomes: Failed pneumatic reduction, perforation during attempted pneumatic reduction, intestinal resection, ileostomy, relook laparotomy, intensive care unit admission and mortality. A total of 108 cases were found of which 11 were excluded from data analysis. Results: Sixty eight percent of cases were from CHBH and a total of 57% of cases were referred from surrounding medical facilities. 62 of 97 cases had an attempted pneumatic reduction with a 51.6% (32/62) success rate and an overall success rate of 32/97, 33%. Seven cases developed pneumoperitoneum during pneumatic reduction. A total of 65 cases underwent surgical management. Of those 81.5% (53/65) underwent intestinal resection. Ileostomy diversion was necessary in 13.8% (9/65) of operative cases and 11% (7/65) needed a second surgical procedure during the initial presenting admission. An overall mortality rate of 9.3% (9/97) is noted. Conclusion: Intussusception in Johannesburg is associated with significant morbidity and mortality. Duration of symptoms and C -­‐ reactive protein levels are predictive for clinical outcomes in paediatric intussusception

The Limits to Wage Growth: Measuring the Growth Rate of Wages For Recent Welfare Leavers

We study the rate of wage growth among welfare leavers in the Self Sufficiency Program (SSP), an experimental earnings subsidy offered to long-term welfare recipients in Canada. Single parents who started working in response to the SSP incentive are younger, less educated, and have more young children than those who would have been working regardless of the program. They also earn relatively low wages in their first few months of work: typically within $1 of the minimum wage. Despite these differences, their rate of wage growth is similar to other welfare leavers. We estimate that people who were induced to work by SSP experienced real wage growth of about 2.5 - 3 percent per year - a rate consistent with conventional measures of the return to experience for similar workers.