The Modified Imitation Game: A Method for Measuring Interactional Expertise

The study of the sociology of scientific knowledge distinguishes between contributory and interactional experts. Contributory experts have practical expertise—they can “walk the walk.” Interactional experts have internalized the tacit components of expertise—they can “talk the talk” but are not able to reliably “walk the walk.” Interactional expertise permits effective communication between contributory experts and others (e.g., laypeople), which in turn facilitates working jointly toward shared goals. Interactional expertise is attained through long-term immersion into the expert community in question. To assess interactional expertise, researchers developed the imitation game—a variant of the Turing test—to test whether a person, or a particular group, possesses interactional expertise of another. The imitation game, which has been used mainly in sociology to study the social nature of knowledge, may also be a useful tool for researchers who focus on cognitive aspects of expertise. In this paper, we introduce a modified version of the imitation game and apply it to examine interactional expertise in the context of blindness. Specifically, we examined blind and sighted individuals’ ability to imitate each other in a street-crossing scenario. In Phase I, blind and sighted individuals provided verbal reports of their thought processes associated with crossing a street—once while imitating the other group (i.e., as a pretender) and once responding genuinely (i.e., as a non-pretender). In Phase II, transcriptions of the reports were judged as either genuine or imitated responses by a different set of blind and sighted participants, who also provided the reasoning for their decisions. The judges comprised blind individuals, sighted orientation-and-mobility specialists, and sighted individuals with infrequent socialization with blind individuals. Decision data were analyzed using probit mixed models for signal-detection-theory indices. Reasoning data were analyzed using natural-language-processing (NLP) techniques. The results revealed evidence that interactional expertise (i.e., relevant tacit knowledge) can be acquired by immersion in the group that possesses and produces the expert knowledge. The modified imitation game can be a useful research tool for measuring interactional expertise within a community of practice and evaluating practitioners’ understanding of true experts.

Concordance of qualitative bone scintigraphy results with presence of clinical complex regional pain syndrome 1: meta-analysis of test accuracy studies

BACKGROUND

To date, no attempt has been made to investigate the agreement between qualitative bone scintigraphy (BS) and the presence of complex regional pain syndrome 1 (CRPS 1) and the agreement between a negative BS in the absence of CRPS 1.

AIMS

To summarize the existing evidence quantifying the concordance of qualitative BS in the presence or absence of clinical CRPS 1.

DATA SOURCES

We searched Medline, Embase, Dare and the Cochrane Library and screened bibliographies of all included studies.

STUDY ELIGIBILITY CRITERIA

We selected diagnostic studies investigating the association between qualitative BS results and the clinical diagnosis of CRPS 1. The minimum requirement for inclusion was enough information to fill the two-by-two tables.

RESULTS

Twelve studies met our inclusion criteria and were included in the meta-analysis. The pooled mean sensitivity of 12 two-by-two tables was 0.87 (95% CI, 0.68-0.97) and specificity was 0.69 (95% CI, 0.47-0.85). The pooled mean sensitivity for the subgroup with clearly defined diagnostic criteria (seven two-by-two tables) was 0.80 (95% CI, 0.44-0.95) and specificity was 0.73 (95% CI, 0.40-0.91).

CONCLUSIONS

Based on this study, clinicians must be advised that a positive BS is not necessarily concordant with presence of absence or CRPS 1. Given the moderate level of concordance between a positive BS in the absence of clinical CRPS 1, discordant results potentially impede the diagnosis of CRPS 1.

The free radical scavenger alpha-phenyl-tert-butyl nitrone aggravates hippocampal apoptosis and learning deficits in experimental pneumococcal meningitis

The effect of adjuvant therapy with the radical scavenger alpha-phenyl-tert-butyl nitrone (PBN; 100 mg/kg given intraperitoneally every 8 h for 5 days) on brain injury and learning function was evaluated in an infant rat model of pneumococcal meningitis. Meningitis led to cortical necrotic injury (median, 3.97% [range, 0%-38.9%] of the cortex), which was reduced to a median of 0% (range, 0%-30.9%) of the cortex (P<.001) by PBN. However, neuronal apoptosis in the hippocampal dentate gyrus was increased by PBN, compared with that by saline (median score, 1.15 [range, 0.04-1.73] vs. 0.31 [range, 0-0.92]; P<.001). Learning function 3 weeks after cured infection, as assessed by the Morris water maze, was decreased, compared with that in uninfected control animals (P<.001). Parallel to the increase in hippocampal apoptosis, PBN further impaired learning in infected animals, compared with that in saline-treated animals (P<.02). These results contrast with those of an earlier study, in which PBN reduced cortical and hippocampal neuronal injury in group B streptococcal meningitis. Thus, in pneumococcal meningitis, antioxidant therapy with PBN aggravates hippocampal injury and learning deficits.

Obesity as a chronic disease: modern medical and lifestyle management

The United States is in the midst of an epidemic of obesity involving more than one third of the adult population. The prevalence of obesity increased by 40% between 1980 and 1990. Obesity is a chronic disease with a multifactorial etiology including genetics, environment, metabolism, lifestyle, and behavioral components. A chronic disease treatment model involving both lifestyle interventions and, when appropriate, additional medical therapies delivered by an interdisciplinary team including physicians, dietitians, exercise specialists, and behavior therapists offers the best chance for effective obesity treatment. Lifestyle factors such as proper nutrition, regular physical activity, and changes in eating behaviors should be coordinated by this team. This review addresses the modern epidemic of obesity, the strong association between obesity and comorbidities such as coronary heart disease, type 2 diabetes, hypertension, and dyslipidemia. In addition to obesity, the health risks of abdominal obesity and adult weight gain are discussed. The evidence that supports health benefits from modest weight loss (between 5% and 10% of body weight) is evaluated and the 5 key principles of effective obesity therapy are put forward. Obesity is a therapeutic challenge best met by teams of health care professionals, including dietitians and physicians, working together to deliver optimal treatment.

The injection of the delayed neurotoxin tri-O-tolyl phosphate into embryonating chicken eggs and its effects on subsequent chick development

Tri-o-tolyl phosphate (TOTP) was injected into the yolk sac of 120-h chicken embryos at concentrations equivalent to 200,100, 50, 25, or 0 (vehicle control) microgram TOTP/g egg. On d 22 of incubation, all live hatchlings were wing-banded, weighed, and housed in a brooder battery according to treatment level. Birds were examined daily for mortality as well as for development of clinical signs indicative of delayed neurotoxicity. Body weights were determined at weekly intervals for 4 wk. At the end of the fourth week, all birds were killed and necropsied. Liver, spleen, bursa of Fabricius, ovary or testes, and comb (male only) were removed and weighed. The injection of 200 microgram TOTP/g egg significantly depressed hatchability when compared to controls. Chick mortality was not significantly affected by TOTP injection. Clinical symptoms characteristic of delayed neurotoxicity did not develop during the 4-wk observation period. TOTP injection caused a transient growth depression that disappeared by 4 wk of age in both sexes. Organ weighs at 4 wk of age were not consistently affected by the treatment.

Toxicosis of mirex for chick embryos and chickens hatched from eggs inoculated with mirex

Mirex, a hydrocarbon, was mixed with corn oil and injected into chick embryos to test its toxic effect. At a concentration of 0 05 mg mirex/egg, embryo mortality was 40%, at 0.5 mg/egg, mortality was 49%, and at 5.0 mg/egg, mortality reached 81%. Mortality of control eggs injected with corn oil alone was 36%. The body weights of newly hatched chickens and of 4-week-old chicks were not different from those of controls. No clinical signs of disease were seen during the 4 weeks of observation. However, liver weights were increased at all 3 dosages when the birds were killed at 4 weeks, but spleen and bursal weights were not. The results support the decision to discontinue the use of mirex as a pesticide in the environment for controlling the fire ant (Solenopsis sp.) until a better means of presenting it can be found.