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121.
This study aimed to explore health professionals' views and practice regarding the provision of information about health-protective behaviors (e.g., exercise, alcohol consumption, diet) during genetic consultation for breast cancer. Ten genetic counselors participated in three focus groups, and seven medical specialists were interviewed in a focus group or individually. Data was analyzed using the constant comparative method. Findings suggested that health professionals held differing, often opposing, views about the value of health-protective behaviors for women at increased risk of breast cancer. The content and extent of information provided about health-protective behaviors varied widely, and participants expressed a need to form consensus regarding information provision both within and across clinics. The main barriers to providing information regarding health-protective behaviors included the lack of research evidence regarding the impact of these factors and higher priority of other information need to be provided in the limited consultation time. Participants generally did not consider it their role to promote health-protective behaviors, and were concerned about the psychological impact of providing information about behavioral risk factors during genetic consultations. 相似文献
122.
We presented bumblebees a spatial memory task similar to that used with other species (e.g., cats, dogs, and pigeons). In
some conditions we allowed for presence of scent marks in addition to placing local and global spatial cues in conflict. Bumblebees
(Bombus impatiens) were presented an array of artificial flowers within a flight cage, one flower offering reward (S+), while the others were
empty (S−). Bees were tested with empty flowers. In Experiment 1, flowers were either moved at the time of testing or not.
Bees returned to the flower in the same absolute position of the S+ (the flower-array-independent (FAI) position), even if
it was in the wrong position relative to the S− and even when new flower covers prevented the use of possible scent marks.
New flower covers (i.e., without possible scent marks) had the effect of lowering the frequency of probing behavior. In Experiment
2, the colony was moved between training and testing. Again, bees chose the flower in the FAI position of the S+, and not
the flower that would be chosen using strictly memory for a flight vector. Together, these experiments show that to locate
the S+ bees did not rely on scent marks nor the positions of the S−, though the S− were prominent objects close to the goal.
Also, bees selected environmental features to remember the position of the S+ instead of relying upon a purely egocentric
point of view. Similarities with honeybees and vertebrates are discussed, as well as possible encoding mechanisms. 相似文献
123.
In several species, the ability to locate a disappearing object is an adaptive component of predatory and social behaviour.
In domestic dogs, spatial memory for hidden objects is primarily based on an egocentric frame of reference. We investigated
the geometric components of egocentric spatial information used by domestic dogs to locate an object they saw move and disappear.
In experiment 1, the distance and the direction between the position of the animal and the hiding location were put in conflict.
Results showed that the dogs primarily used the directional information between their own spatial coordinates and the target
position. In experiment 2, the accuracy of the dogs in finding a hidden object by using directional information was estimated
by manipulating the angular deviation between adjacent hiding locations and the position of the animal. Four angular deviations
were tested: 5, 7.5, 10 and 15°. Results showed that the performance of the dogs decreased as a function of the angular deviations
but it clearly remained well above chance, revealing that the representation of the dogs for direction is precise. In the
discussion, we examine how and why domestic dogs determine the direction in which they saw an object disappear. 相似文献
124.
The present experiments explored the resolution of activated background information in text comprehension. In Experiment 1, participants read passages that contained an elaboration section that was either consistent or qualified (inconsistent but then corrected to be consistent) with respect to the subsequently presented target sentence (see O'Brien et al., 1998). However, the experiment used two target sentences, and several filler sentences were inserted between the first and second target sentence. The results showed that the reading times for the first target sentence in the qualified elaboration version were significantly longer than those in the consistent elaboration version. These were consistent with O'Brien's study, and further indicated that the basic process captured by the memory-based view appears to generalize to the Chinese reader better than does the here-and-now view. More importantly, the results showed that the reading times for the second target sentence in the qualified elaboration version were as long as those in the consistent elaboration version. These further indicated that the activation of background information not only maintained the coherence of the text, but also allowed for the relevant information to be updated, resulting in a unified information set. When the information was reactivated during ongoing reading, it would be in the form of unified information. In Experiment 2, the first target sentence in each passage from Experiment 1 was converted to a filler sentence, and the second target sentence became the target sentence. The results of Experiment 2 showed that the reading times for the target sentence in the qualified elaboration version were significantly longer than those for the consistent elaboration version. These indicated that the delay between the target sentences and the elaboration section was not responsible for the lack of differences in Experiment 1, and confirmed the conclusion of Experiment 1. 相似文献
125.
Four boys with autism were taught via echoic prompting and constant prompt delay to mand for answers to questions by saying “I don't know please tell me” (IDKPTM). This intervention resulted in acquisition of the IDKPTM response for all 4 participants and in acquisition of correct answers to most of the previously unknown questions for 2 participants. For 1 participant, tangible reinforcement resulted in increased frequency of correct answers, and direct prompting of correct answers was eventually conducted for the final participant. The IDKPTM response generalized to untargeted unknown questions with 3 participants. Results of person and setting generalization probes varied, but some generalization eventually occurred for all participants following additional training or interspersal of probe trials with training trials. 相似文献
126.
Results from studies of observing responses have suggested that stimuli maintain observing owing to their special relationship to primary reinforcement (the conditioned-reinforcement hypothesis), and not because they predict the availability and nonavailability of reinforcement (the information hypothesis). The present article first reviews a study that challenges that conclusion and then reports a series of five brief experiments that provide further support for the conditioned-reinforcement view. In Experiments 1 through 3, participants preferred occasional good news (a stimulus correlated with reinforcement) or no news (a stimulus uncorrelated with reinforcement) to occasional bad news (a stimulus negatively correlated with reinforcement). In Experiment 4 bad news was preferred to no news when the absence of stimulus change following a response to the bad-news option was reliably associated with good news. When this association was weakened in Experiment 5 the results were intermediate. The results support the conclusion that information is reinforcing only when it is positive or useful. As required by the conditioned-reinforcement hypothesis, useless information does not maintain observing. 相似文献
127.
Jean-Yves Baudouin Mathieu Gallay Fabrice Robichon 《Journal of experimental child psychology》2010,107(3):195-206
This study investigated children’s perceptual ability to process second-order facial relations. In total, 78 children in three age groups (7, 9, and 11 years) and 28 adults were asked to say whether the eyes were the same distance apart in two side-by-side faces. The two faces were similar on all points except the space between the eyes, which was either the same or different, with various degrees of difference. The results showed that the smallest eye spacing children were able to discriminate decreased with age. This ability was sensitive to face orientation (upright or upside-down), and this inversion effect increased with age. It is concluded here that, despite early sensitivity to configural/holistic information, the perceptual ability to process second-order relations in faces improves with age and constrains the development of the face recognition ability. 相似文献
128.
Janne V. Kujala Ulla Richardson Heikki Lyytinen 《Journal of mathematical psychology》2010,54(2):247-255
Adaptive learning games should provide opportunities for the student to learn as well as motivate playing until goals have been reached. In this paper, we give a mathematically rigorous treatment of the problem in the framework of Bayesian decision theory. To quantify the opportunities for learning, we assume that the learning tasks that yield the most information about the current skills of the student, while being desirable for measurement in their own right, would also be among those that are efficient for learning. Indeed, optimization of the expected information gain appears to naturally avoid tasks that are exceedingly demanding or exceedingly easy as their results are predictable and thus uninformative. Still, tasks that are efficient for learning may be experienced as too challenging, and the resulting failures can lower motivation. Therefore, in addition to quantifying the expected informational benefit for learning of any prospective task to be presented next, we also model the expected motivational cost of its presentation, measured simply as the estimated probability of failure in our example model. We propose a “learner-friendly” adaptation algorithm that chooses the learning tasks by optimizing the expected benefit divided by the expected cost. We apply this algorithm to a Rasch-like student model implemented within a real-world application and present initial results of a pilot experiment. 相似文献
129.
130.
随着民航行业的快速发展,飞机登机牌的使用率越来越高,而不同航空公司所采用的登机牌在信息内容和布局设计等方面均缺乏相关的设计规范,因此有必要从可用性角度对登机牌进行系统的研究.首先,采用KANO问卷法对登机牌上的文字信息要素进行研究,并基于研究结果设计出新登机牌;然后,从搜索绩效和主观偏好两个方面对新旧登机牌进行比较评价研究.结果显示:①登机牌上必须呈现的信息主要包括登机时间、登机口、航班号、座位号、姓名、日期和目的地七项必要信息,以及可提高旅客使用体验的预计飞行时间信息,但登机牌上不能呈现旅客身份证号码等个人隐私信息;②基于信息要素研究结果重新布局设计的新登机牌在搜索绩效和主观偏好方面均显著优于现有登机牌.本研究结果可为将来的登机牌设计提供科学依据. 相似文献