Molecular computation: RNA solutions to chess problems. (1/310)

We have expanded the field of "DNA computers" to RNA and present a general approach for the solution of satisfiability problems. As an example, we consider a variant of the "Knight problem," which asks generally what configurations of knights can one place on an n x n chess board such that no knight is attacking any other knight on the board. Using specific ribonuclease digestion to manipulate strands of a 10-bit binary RNA library, we developed a molecular algorithm and applied it to a 3 x 3 chessboard as a 9-bit instance of this problem. Here, the nine spaces on the board correspond to nine "bits" or placeholders in a combinatorial RNA library. We recovered a set of "winning" molecules that describe solutions to this problem.  (+info)

Cooperation through image scoring in humans. (2/310)

The "tragedy of the commons," that is, the selfish exploitation of resources in the public domain, is a reason for many of our everyday social conflicts. However, humans are often more helpful to others than evolutionary theory would predict, unless indirect reciprocity takes place and is based on image scoring (which reflects the way an individual is viewed by a group), as recently shown by game theorists. We tested this idea under conditions that control for confounding factors. Donations were more frequent to receivers who had been generous to others in earlier interactions. This shows that image scoring promotes cooperative behavior in situations where direct reciprocity is unlikely.  (+info)

Impaired social response reversal. A case of 'acquired sociopathy'. (3/310)

In this study, we report a patient (J.S.) who, following trauma to the right frontal region, including the orbitofrontal cortex, presented with 'acquired sociopathy'. His behaviour was notably aberrant and marked by high levels of aggression and a callous disregard for others. A series of experimental investigations were conducted to address the cognitive dysfunction that might underpin his profoundly aberrant behaviour. His performance was contrasted with that of a second patient (C.L.A.), who also presented with a grave dysexecutive syndrome but no socially aberrant behaviour, and five inmates of Wormwood Scrubs prison with developmental psychopathy. While J.S. showed no reversal learning impairment, he presented with severe difficulty in emotional expression recognition, autonomic responding and social cognition. Unlike the comparison populations, J.S. showed impairment in: the recognition of, and autonomic responding to, angry and disgusted expressions; attributing the emotions of fear, anger and embarrassment to story protagonists; and the identification of violations of social behaviour. The findings are discussed with reference to models regarding the role of the orbitofrontal cortex in the control of aggression. It is suggested that J.S.'s impairment is due to a reduced ability to generate expectations of others' negative emotional reactions, in particular anger. In healthy individuals, these representations act to suppress behaviour that is inappropriate in specific social contexts. Moreover, it is proposed that the orbitofrontal cortex may be implicated specifically either in the generation of these expectations or the use of these expectations to suppress inappropriate behaviour.  (+info)

Who wants to be a physician? An educational tool for reviewing pulmonary physiology. (4/310)

Traditional review sessions are typically focused on instructor-based learning. However, experts in the field of higher education have long recommended teaching modalities that incorporate student-based active-learning strategies. Given this, we developed an educational game in pulmonary physiology for first-year medical students based loosely on the popular television game show Who Wants To Be A Millionaire. The purpose of our game, Who Wants To Be A Physician, was to provide students with an educational tool by which to review material previously presented in class. Our goal in designing this game was to encourage students to be active participants in their own learning process. The Who Wants To Be A Physician game was constructed in the form of a manual consisting of a bank of questions in various areas of pulmonary physiology: basic concepts, pulmonary mechanics, ventilation, pulmonary blood flow, pulmonary gas exchange, gas transport, and control of ventilation. Detailed answers are included in the manual to assist the instructor or player in comprehension of the material. In addition, an evaluation instrument was used to assess the effectiveness of this instructional tool in an academic setting. Specifically, the evaluation instrument addressed five major components, including goals and objectives, participation, content, components and organization, and summary and recommendations. Students responded positively to our game and the concept of active learning. Moreover, we are confident that this educational tool has enhanced the students' learning process and their ability to understand and retain information.  (+info)

Evaluation of microcomputer nutritional teaching games in 1,876 children at school. (5/310)

OBJECTIVE: We evaluated in a prospective study microcomputer nutritional teaching games and their contribution to the children's acquisition of nutritional knowledge and improvement of eating habits. MATERIAL AND METHODS: One thousand eight hundred seventy-six children aged 7-12 years took part in this study at school. All 16 schools of the same school district were randomized into two groups: games group and control group, both receiving conventional nutritional teaching by their teachers. The children in the games group played computer games during the conventional nutritional teaching period (2 hours a week for 5 weeks). At completion of the study, dietetic knowledge and dietary records were evaluated in both groups. RESULTS: Dietary knowledge tests results were better in the games group (p<0.001). The children in the games group had a significantly better balanced diet for an energy intake of about 1900 kilocalories: more carbohydrate (46.4 +/- 0.2% vs 45.7 +/- 0.2%, p<0.05), less fat (37.1 +/- 0.1% vs 37.6 +/- 0.2%, p<0.05), less protein (16.5 +/- 0.1% vs 16.7 +/- 0.1%, p<0.05), less saccharose (11.5 +/- 0.1% vs 12.2 +/- 0.2%, p<0.001), more calcium (p<0.001) and more fiber (p<0.05). The games group had a better snack at 10 a.m., a less copious lunch and less nibbling (p<0.001). CONCLUSION: The children in the games group had slightly but significantly better nutritional knowledge and dietary intake compared to children in the control group. Using our micro computer nutritional teaching games at school provides an additional and modern support to conventional teaching.  (+info)

Wisconsin Card Sorting revisited: distinct neural circuits participating in different stages of the task identified by event-related functional magnetic resonance imaging. (6/310)

The Wisconsin Card Sorting Task (WCST) has been used to assess dysfunction of the prefrontal cortex and basal ganglia. Previous brain imaging studies have focused on identifying activity related to the set-shifting requirement of the WCST. The present study used event-related functional magnetic resonance imaging (fMRI) to study the pattern of activation during four distinct stages in the performance of this task. Eleven subjects were scanned while performing the WCST and a control task involving matching two identical cards. The results demonstrated specific involvement of different prefrontal areas during different stages of task performance. The mid-dorsolateral prefrontal cortex (area 9/46) increased activity while subjects received either positive or negative feedback, that is at the point when the current information must be related to earlier events stored in working memory. This is consistent with the proposed role of the mid-dorsolateral prefrontal cortex in the monitoring of events in working memory. By contrast, a cortical basal ganglia loop involving the mid-ventrolateral prefrontal cortex (area 47/12), caudate nucleus, and mediodorsal thalamus increased activity specifically during the reception of negative feedback, which signals the need for a mental shift to a new response set. The posterior prefrontal cortex response was less specific; increases in activity occurred during both the reception of feedback and the response period, indicating a role in the association of specific actions to stimuli. The putamen exhibited increased activity while matching after negative feedback but not while matching after positive feedback, implying greater involvement during novel than routine actions.  (+info)

"Survivor" torches "Who Wants to Be a Physician?" in the educational games ratings war. (7/310)

We recently developed an educational game for reviewing respiratory physiology in a large classroom. The "Who Wants to be a Physician?" game encouraged medical students to be active participants in the learning process. An evaluation of the game documented that students enjoyed the active format, and the students reported that the game enhanced their ability to understand and retain information. However, the evaluation also revealed that the game had limitations. Specifically, the students recommended the use of multiple-choice questions to match the Medical Board Examination format and to speed up the game (i.e., cover more topics). The students also wanted to increase their level of participation and interaction. Finally, we wanted to emphasize the benefits of peer instruction as a collaborative learning tool. To address these limitations, we designed a new game, "Survivor." Survivor incorporated multiple-choice questions and emphasized peer instruction and a capacity to gather information and solve novel problems. In addition, participation was increased by including the student audience in the game. Finally, an evaluation instrument was utilized to assess the effectiveness of this instructional tool in an academic setting. As a result of these improvements, the evaluation documents that the newly developed tool is a more effective educational game that couples fun and creative excitement with proven and effective educational concepts.  (+info)

The role of the amygdala in signaling prospective outcome of choice. (8/310)

Can brain activity reveal a covert choice? Making a choice often evokes distinct emotions that accompany decision processes. Amygdala has been implicated in choice behavior that is guided by a prospective negative outcome. However, its specific involvement in emotional versus cognitive processing of choice behavior has been a subject of controversy. In this study, the human amygdala was monitored by functional magnetic resonance imaging (fMRI) while subjects were playing in a naturalistic choice paradigm against the experimenter. In order to win, players had to occasionally choose to bluff their opponent, risk "getting caught," and suffer a loss. A critical period, when choice has been made but outcome was still unknown, activated the amygdala preferentially following the choice that entailed risk of loss. Thus, the response of the amygdala differentiated between subject's covert choice of either playing fair or foul. These results support a role of the amygdala in choice behavior, both in the appraisal of inherent value of choice and the signaling of prospective negative outcomes.  (+info)