Eye-movements support chronometric imagery performance even when the task is occluded

ABSTRACT

Mental chronometry has often been used to provide a temporal comparison between executed and imagined movements, with smaller discrepancies indicating more accurate image production and better imagery performance. In this study, we examined the importance of retinal and extra-retinal information in the performance of simple, sequential movements. After physical practice of four activities of daily living (Southampton Hand Assessment Procedure), nineteen participants imagined completing the same tasks with: 1) free eye-movements and visible objects, 2) free eye-movements and no visibility of the objects, and 3) constrained eye-movements and visible objects. Results suggested imagery performance was slower/less accurate compared to physical execution when the eyes were constrained. Conversely, chronometric imagery performance was unaffected with free eye movements, even when task-specific visual information was occluded. This study highlights the crucial role that eye-movements play in the regulation of the temporal aspects of imagery even when retinal information is absent, suggesting that temporal sequencing of imagined actions is largely dependent on extra-retinal information sources.     

Decision theory and artificial intelligence II: The hungry monkey

This paper describes a problem-solving framework In which aspects of mathematical decision theory are incorporated into symbolic problem-solving techniques currently predominant in artificial intelligence. The utility function of decision theory IS used to reveal tradeoffs among competing strategies for achieving various goals, taking into account such factors as reliability, the complexity of steps in the strategy, and the value of the goal. The utility function on strategies can therefore be used as a guide when searching for good strategies. It is also used to formulate solutions to the problems of how to acquire a world model, how much planning effort is worthwhile, and whether verification tests should be performed. These techniques are illustrated by application to the classic monkey and bananas problem.     

医患关系中医生沟通能力培训模式的研究进展

从医生沟通能力的视角出发，改善医患关系的相关促进技术主要包括线下课程培训和计算机网络技术的实时交互式模拟训练等形式。其中，线下课程培训是当前医生沟通能力提升的主要促进技术，分别以沟通技能培训Comskil模型和真实工作场所中的医生沟通能力培训周期模型作为理论支撑，形成了针对特殊领域的“告知坏消息”沟通培训课程和处方对话培训课程。线下的课程培训因其在培训时间和培训师能力要求方面的局限性，促使了计算机模拟在医生沟通能力训练上的运用，从而形成了基于计算机的实时交互式模拟训练系统。随着科学技术的发展，未来将会有更多的新技术加入到实时交互式模拟训练中来。     

Passing markers: A theory of contextual influence in language comprehension

Most Artificial Intelligence theories of language either assume a syntactic component which serves as “front end” for the rest of the system, or else reject all attempts at distinguishing modules within the comprehension system. In this paper we will present an alternative which, while keeping modularity, will account for several puzzles for typical “syntax first” theories. The major addition to this theory is a “marker passing” (or “spreading activation”) component, which operates in parallel to the normal syntactic component.     

The role of affect in narratives

Affect states and reactions commonly occur in narratives. This paper discusses the importance of affect knowledge and processing in the context of BORIS, a computer program which reads and answers questions about narratives involving multiple sources of knowledge. There are several reasons why affects are important in a process model of narrative comprehension: For one thing, affects describe goal situations and signal the occurrence of expectation failures. Affective reactions also serve as an indication of the status of interpersonal relationships. Finally, affects influence the kinds of thematic structures which become instantiated in episodic memory.     

Categorizing numeric information for generalization

Learning programs that generalize from real-world examples will have to deal with many different kinds of data. Continuous numeric data can cause problems for algorithms that search for examples with identical property values. These problems can be surmounted by categorizing the numeric data. However, this process has problems of its own. In this paper, we look at the need for categorizing numeric data and several methods for doing so. We concentrate on the use of generalization-based memory, a memory organization where actual examples are stored along with generalizations, which leads to a generalization-based categorization algorithm. We also consider how to use a number heuristic, looking for gaps. These methods have been implemented in the UNIMEM computer system. Examples are presented of these algorithms categorizing data about the states of the United States.     

Children's kinematic false memories

ABSTRACT

Individuals misrecognise as seen the never-presented natural continuation of an action. These false memories derive from the running of kinematic mental models of the actions seen, which rest on motor inferences from implicit knowledge. We verified an implied prediction: kinematic false memories should be detectable even in children. The participants in our experiments first observed photos in which actors were about to perform actions on objects. At recognition they were presented with the original photos, plus (a) distractors representing the unseen natural continuation of the original actions, (b) distractors representing the beginning of other actions on the same objects and (c) distractors representing completed different actions on the same objects. In contrast to the original studies in which participants expressed their confidence in recognition, in our experiments the participants catgorirzed the action as seen or not seen. After replicating the original results with the dichotomous recognition task (Experiment 1), we detected spontaneous false memories also in children (Experiment 2).     

Establishing conventional communication systems: Is common knowledge necessary?

How do communities establish shared communication systems? The Common Knowledge view assumes that symbolic conventions develop through the accumulation of common knowledge regarding communication practices among the members of a community. In contrast with this view, it is proposed that coordinated communication emerges a by‐product of local interactions among dyads. A set of multi‐agent computer simulations show that a population of “egocentric” agents can establish and maintain symbolic conventions without common knowledge. In the simulations, convergence to a single conventional system was most likely and most efficient when agents updated their behavior on the basis of local rather than global, system‐level information. The massive feedback and parallelism present in the simulations gave rise to phenomena that are often assumed to result from complex strategic processing on the part of individual agents. The implications of these findings for the development of theories of language use are discussed.