Active heading control in simulated flight based on vertically extended contours

In two experiments, we manipulated the properties of 3-D objects and terrain texture in order to investigate their effects on active heading control during simulated flight. Simulated crosswinds were used to introduce a rotational component into the retinal flow field that presumably provided the visual cues used for heading control An active control task was used so that the results could be generalized to real-world applications such as flight simulation. In Experiment 1, we examined the effects of three types of terrain, each of which was presented with and without 3-D objects (trees), and found that the presence of 3-D objects was more important than terrain texture for precise heading control In Experiment 2, we investigated the effects of varying the height and density of 3-D objects and found that increasing 3-D object density improved heading control, but that 3-D object height had only a small effect. On the basis of these results, we conclude that the vertical contours improved active heading control by enhancing the motion parallax information contained in the retinal flow.     

A Time for Silence? Its Possibilities for Dialogue and for Reflective Learning

From the beginning of history sounds have played a fundamentally important role in humanity’s development as ways of expression and of communication. However in contemporary western society, and indeed globally, we are experiencing an excess of speech and a relentless encouragement to expression. Such excess indicates a misunderstanding about what expression and dialogue should be. This condition encourages us to think about silence, solitude and contemplation and the role they might play in restoring the realm of personal understanding of the Self and of one’s authentic experience of the Other. The purpose of this article is to explore the potency of a silence that arises from our participation in the world. We present first some ideas about silence as a human phenomenon. This is followed by an examination of silence and language, an investigation of silence in dialogue, and of its educational implications. The article concludes by emphasising the value of silence as potency in itself, assisting in recovering the expressive powers of language. We argue that it is important to understand the positive status of silence in order to recognise and avoid repressive speech and to introduce its potential for reflective learning.     

Coherent plaids are preattentively more than the sum of their parts

We investigated whether plaids activate preattentive mechanisms that are distinct from those activated by their component gratings. Observers searched for a target plaid, the sum of two perpendicular components in a circular window (radius = 0.65°). The target was present on half the trials. On all trials, half of the distractors had the same frequency and orientation as one component of the plaid, and the rest were the same as the other component. The target and the distractors were arrayed evenly on a circle (radius = 2.36°) around fixation. Target and distractor contrasts were randomly perturbed up to ±30%. The following results held for each of the 6 participants tested. (1) When F1 = 2 c/deg and F2 = 5.25 c/deg, response times (RTs) increased significantly when set size (number of distractors plus target, if present) was increased from four to eight. (2) When the spatial frequencies of both plaid components were the same (i.e., both 2 c/deg or both 5.25 c/deg), RTs increased very slightly, if at all, when set size was increased from four to eight. These results suggest the existence of a preattentive, plaid-sensitive mechanism with band-limited input that does not respond to individual grating components.     

Tuomela on deductive explanation

Almost every formal model of explanation thus far proposed has been demonstrated to be faulty. In this paper, a new model, proposed by Raimo Tuomela, is also demonstrated to be faulty. In particular, one condition of the model is shown to be too restrictive, and another condition of the model is shown to be too permissive.This research was supported by a grant from the Killam Foundation, administered by the Canada Council.     

When ideology matters: Moral conviction and the association between ideology and policy preferences in the Israeli–Palestinian conflict

Do people's policy preferences toward outgroups in intractable conflict consistently correspond with political ideology? To what extent are policy‐related cleavages between the political right and left in such contexts fueled by moral conviction and emotions? Analyses of a survey of Jewish‐Israelis (N = 119) conducted immediately after a war between Israelis and Palestinians revealed little to no ideological differences in acceptance of “collateral damage,” support for retribution, or support for compromise when positions about the Israeli–Palestinian conflict were devoid of moral fervor. Those on the left and right endorsed polarized policy preferences only when their positions about the conflict were held with moral conviction. Presence or absence of guilt about harm to Palestinians mediated the effects of moral conviction on policy preferences in this context. Copyright © 2013 John Wiley & Sons, Ltd.     

Grace and Christianity's Requirement: Moral Striving in Kierkegaard's Judge for Yourself!

In his later work Judge for Yourself, Kierkegaard presents a view of the Christian life that appears to counter several recent interpretations which situate Kierkegaard within a classical Protestant account of justification and sanctification. I introduce briefly these interpretations and then turn to a reading of Judge for Yourself, showing that Kierkegaard offers an account of grace and moral striving which resists these interpretations. He resists them, yet he presents a Christianity that both rejects works‐righteousness and graciously embraces those who confess their failure to do what Christianity requires.     

Structural packaging in the input to language learning: Contributions of prosodic and morphological marking of phrases to the acquisition of language

The linguistic input to language learning is usually thought to consist of simple strings of words. We argue that input must also include information about how words group into syntactic phrases. Natural languages regularly incorporate correlated cues to phrase structure, such as prosody, function words, and concord morphology. The claim that such cues are necessary for successful acquisition of syntax was tested in a series of miniature language learning experiments with adult subjects. In each experiment, when input included some cue marking the phrase structure of sentences, subjects were entirely successful in learning syntax; in contrast, when input lacked such a cue (but was otherwise identical), subjects failed to learn significant portions of syntax. Cues to phrase structure appear to facilitate learning by indicating to the learner those domains within which distributional analyses may be most efficiently pursued, thereby reducing the amount and complexity of required input data. More complex target systems place greater premiums on efficient analysis; hence, such cues may be even more crucial for acquisition of natural language syntax. We suggest that the finding that phrase structure cues are a necessary aspect of language input reflects the limited capacities of human language learners; languages may incorporate structural cues in part to circumvent such limitations and ensure successful acquisition.     

Origin and history of an early TAT card: picture C

The origin and history of Picture C is reviewed, and the role that David Ricks played in preserving many original TAT materials is presented. I suggest that a process similar to that employed with Picture C may have been used in the development of the other "old standbys." The unusual directions for the use of Picture C may possibly suggest awareness by C. D. Morgan and Murray of Schwartz's earlier work with the picture-story technique.