Dynamic Visual Acuity

Forty subjects took part in a one-handed catching task in which the period for which the mechanically projected tennis ball was illuminated in flight was varied systematically. Additionally, they were tested for (a) static visual acuity and (b) dynamic visual acuity, in which angular velocity was varied. As expected, both viewing period in the catching task and angular velocity in the acuity task were significant variables in performance. Correlation and principal-components analyses confirmed the findings of a previous experiment in that the correlated static visual acuity tasks were unrelated to both dynamic visual acuity (even when angular velocity was only 75°/sec) and catching performance. Further, dynamic acuity and catching were related under the majority of the combinations, and most frequently at the highest angular velocity, a fact which suggested that the dynamic element in both tasks is the common factor.     

Temporal coordination between performing musicians

Many common behaviours require people to coordinate the timing of their actions with the timing of others' actions. We examined whether representations of musicians' actions are activated in coperformers with whom they must coordinate their actions in time and whether coperformers simulate each other's actions using their own motor systems during temporal coordination. Pianists performed right-hand melodies along with simple or complex left-hand accompaniments produced by themselves or by another pianist. Individual performers' preferred performance rates were measured in solo performance of the right-hand melody. The complexity of the left-hand accompaniment influenced the temporal grouping structure of the right-hand melody in the same way when it was performed by the self or by the duet partner, providing some support for the action corepresentation hypothesis. In contrast, accompaniment complexity had little influence on temporal coordination measures (asynchronies and cross-correlations between parts). Temporal coordination measures were influenced by a priori similarities between partners' preferred rates; partners who had similar preferred rates in solo performance were better synchronized and showed mutual adaptation to each other's timing during duet performances. These findings extend previous findings of action corepresentation and action simulation to a task that requires precise temporal coordination of independent yet simultaneous actions.     

Adults see vision to be more informative than it is

Humans gain a wide range of knowledge through interacting with the environment. Each aspect of our perceptual experiences offers a unique source of information about the world—colours are seen, sounds heard and textures felt. Understanding how perceptual input provides a basis for knowledge is thus central to understanding one's own and others' epistemic states. Developmental research suggests that 5-year-olds have an immature understanding of knowledge sources and that they overestimate the knowledge to be gained from looking. Without evidence from adults, it is not clear whether the mature reasoning system outgrows this overestimation. The current study is the first to investigate whether an overestimation of the knowledge to be gained from vision occurs in adults. Novel response time paradigms were adapted from developmental studies. In two experiments, participants judged whether an object or feature could be identified by performing a specific action. Adult participants found it disproportionately easy to accept looking as a proposed action when it was informative, and difficult to reject looking when it was not informative. This suggests that adults, like children, overestimate the informativeness of vision. The origin of this overestimation and the implications that the current findings bear on the interpretation of children's overestimation are discussed.     

MIRACLES AND TWO ACCOUNTS OF SCIENTIFIC LAWS

Since early modernity, it has often been assumed that miracles are incompatible with the existence of the natural laws utilized in the sciences. This paper argues that this assumption is largely an artifact of empiricist accounts of laws that should be rejected for reasons internal to philosophy of science, and that no such incompatibility arises on the most important alternative interpretations, which treat laws as expressions of forces, dispositions, or causal powers.     

"The End of all our Exploring" in Science and Theology

Abstract. The present malaise of religion—and of theology, its intellectual formulation—in Western society is analyzed, with some personal references, especially with respect to its history in the United Kingdom and the United States. The need for a more open theology that takes account of scientific perspectives is urged. An indication of the understandings of God and of God's relation to the world which result from an exploration starting from scientific perspectives is expounded together with their fruitful relation to some traditional themes. The implications of this for the future of theology are suggested, not least in relation to the new phase, beginning in 2003, of the development of the Zygon Center for Religion and Science. In a concluding reflection the hope is expressed that the shared global experience and perspectives generated by the sciences might form a more common and acceptable starting point than hitherto for the exploration towards God of the seekers of many religious traditions and of none.     

THEOLOGY AND PHYSICS FORTY YEARS LATER

Abstract. Almost forty years later I look back on a 1966 article on theology and physics by Sanford Brown and my response published with it. I reflect on his hope that theological seminaries would give attention to the methods used in scientific inquiry. I compare our comments with subsequent thought on three issues: (1) the role of models in science and religion; (2) the relation of wholes to parts in physics and other sciences and the debate over reductionism and emergence; and (3) the implications of quantum physics for theology, including the possibility of divine action at the quantum level.     

Epistemic means and ends: a reply to Hofmann

How is epistemic justification related to knowledge? Is it, as widely thought, constitutive of knowledge? Is it merely a means to knowledge, or merely a means to something else, such as truth? In a recent article in this journal, Hofmann (2005, Synthese, 146(3), 357–369) addresses these questions in attempting to defend an important argument articulated by Sartwell (1992, The Journal of Philosophy, 89(4), 167–180) and reconstructed and criticized by Le Morvan (2002, Erkenntnis: An International Journal of Analytic Philosophy, 56(2), 151–168). This Sartwellian argument purported to show that, since epistemic justification is of merely instrumental value, it is not constitutive of knowledge. In this paper, I argue that Hofmann’s defense of Sartwell fails, but that its failure brings to light some important lessons concerning the nature of justification and its relationship to truth and knowledge.     

自闭症碎镜理论之迷思:缘起、问题与前景

自闭症患者在社会沟通和交往障碍上主要涉及社会情感互动缺陷、非语言行为交流缺陷、发展维持和理解人际关系的缺陷。该群体在社会认知过程中潜在自动的直觉成分受损被视为其独特的临床症状。鉴于镜像神经元系统在社会认知的直觉成分上扮演的重要角色,该系统的功能障碍假说(或称"碎镜"理论)被提出并用以解释自闭症的成因及其异常表现。然而,在经历了10年的发展与证据检验后,该理论潜在的问题逐渐暴露。当前的研究显示,迄今为止人类镜像神经元系统的研究存在内在缺陷,镜像神经元系统至多是社会认知的附带原因,该系统功能障碍也并非自闭症患者社会认知障碍的必要条件。碎镜理论面临来自临床行为研究与认知神经科学实验证据的广泛质疑。未来,伴随自闭症研究对象的变化,镜像神经元的社会响应学说的提出,双个体范式、第二人称神经科学范式与计算精神病学的兴起,镜像神经元与自闭症的真正关系将有望得以阐明。     

Interactions of reading and semantics along the ventral visual processing stream

Converging evidence supports a distributed-plus-hub view of semantic processing, in which there are distributed modular semantic sub-systems (e.g., for shape, colour, and action) connected to an amodal semantic hub. Furthermore, object semantic processing of colour and shape, and lexical reading and identification, are processed mainly along the ventral stream, while action semantic processing occurs mainly along the dorsal stream. In Experiment 1, participants read a prime word that required imagining either the object or action referent, and then named a lexical word target. In Experiments 2 and 3, participants performed a lexical decision task (LDT) with the same targets as in Experiment 1, in the presence of foils that were legal nonwords (NW; Experiment 2) or pseudohomophones (PH; Experiment 3). Semantic priming was similar in effect size regardless of prime type for naming, but was greater for object primes than action primes for the LDT with PH foils, suggesting a shared-stream advantage when the task demands focus on orthographic lexical processing. These experiments extend the distributed-plus-hub model, and provide a novel paradigm for further research.