Two memories for geographical slant: Separation and interdependence of action and awareness

The present study extended previous findings of geographical slant perception, in which verbal judgments of the incline of hills were greatly overestimated but motoric (haptic) adjustments were much more accurate. In judging slant from memory following a brief or extended time delay, subjects’ verbal judgments were greater than those given when viewing hills. Motoric estimates differed depending on the length of the delay and place of response. With a short delay, motoric adjustments made in the proximity of the hill did not differ from those evoked during perception. When given a longer delay or when taken away from the hill, subjects’ motoric responses increased along with the increase in verbal reports. These results suggest two different memorial influences on action. With a short delay at the hill, memory for visual guidance is separate from the explicit memory informing the conscious response. With short or long delays away from the hill, short-term visual guidance memory no longer persists, and both motor and verbal responses are driven by an explicit representation. These results support recent research involving visual guidance from memory, where actions become influenced by conscious awareness, and provide evidence for communication between the “what” and “how” visual processing systems.     

Playing in the Presence of God: wonder,wisdom and education

Biblical poetry provides a picture of Woman Wisdom or Sophia and her relation with God and humans which does not revolve around traditional notions of sin, guilt and redemption. Rather, it centres in joy, learning, wisdom, playing in God's presence and wonder. Exploring biblical wisdom and the human experience of wonder illumines the teaching‐learning relation and the importance of playful wonder in spiritual formation.     

Skating down a steeper slope: fear influences the perception of geographical slant

Previous studies have shown that conscious awareness of hill slant is overestimated, but visually guided actions directed at hills are relatively accurate. Also, steep hills are consciously estimated to be steeper from the top than the bottom, possibly because they are dangerous to descend. In the present study, participants stood at the top of a hill either on a skateboard or a wooden box of the same height. They gave three estimates of the slant: a verbal report, a visually matched estimate, and a visually guided action. Fear of descending the hill was also assessed. Those participants who were scared (by the skateboard) consciously judged the hill to be steeper than unafraid participants. However, the visually guided action measure was accurate across conditions. These results suggest that explicit awareness of slant is influenced by the fear associated with a potentially dangerous action that could be performed on the hill.     

Seeing beyond the target: environmental context affects distance perception

It is commonly assumed that perceived distance in full-cue, ecologically valid environments is redundantly specified and approximately veridical. However, recent research has called this assumption into question by demonstrating that distance perception varies in different types of environments even under full-cue viewing conditions. We report five experiments that demonstrate an effect of environmental context on perceived distance. We measured perceived distance in two types of environments (indoors and outdoors) with two types of measures (perceptual matching and blindwalking). We found effects of environmental context for both egocentric and exocentric distances. Across conditions, within individual experiments, all viewer-to-target depth-related variables were kept constant. The differences in perceived distance must therefore be explained by variations in the space beyond the target.     

Asymmetrical Body Perception: A Possible Role for Neural Body Representations

ABSTRACT— Perception of one's body is related not only to the physical appearance of the body, but also to the neural representation of the body. The brain contains many body maps that systematically differ between right- and left-handed people. In general, the cortical representations of the right arm and right hand tend to be of greater area in the left hemisphere than in the right hemisphere for right-handed people, whereas these cortical representations tend to be symmetrical across hemispheres for left-handers. We took advantage of these naturally occurring differences and examined perceived arm length in right- and left-handed people. When looking at each arm and hand individually, right-handed participants perceived their right arms and right hands to be longer than their left arms and left hands, whereas left-handed participants perceived both arms accurately. These experiments reveal a possible relationship between implicit body maps in the brain and conscious perception of the body.     

Stereokinetic effect and its relation to the kinetic depth effect.

The stereokinetic effect (SKE) has been defined and studied by nested circular patterns rotating on a turntable. Circles must appear not to rotate as they revolve, which in turn results in their appearing to translate relative to one another. A powerful illusion of object depth results even though the individual circles do not undergo an appropriate foreshortening consistent with their apparent changes in slant. It is suggested and tested that the SKE is based on the changing positions between the nested contours despite the absence of any change within each contour, whereas the kinetic depth effect (KDE) entails both kinds of change. It follows that a turntable method of presentation is not necessary, and between-contour transformations can be simulated by computer animation. Displays consisting of simple translations were shown to evoke robust depth impressions as were patterns consisting of contours of varying shapes. Comparisons of the depth, compellingness, and rigidity of matched SKE and KDE displays are reported. The SKE is taken to be paradigmatic for how the visual system perceives depth when observing small object rotations that occur in everyday situations.     

Converging operations revisited: assessing what infants perceive using discrimination measures

The study of visual perception in human infants is confronted by a number of special problems arising from the inaccessibility of verbal reports. In this paper, we discuss the experimental strategy of converging operations in the context of investigating the phenomenal experience of infants. The goal of this strategy is to logically and empirically delimit alternative explanations for a given behavior. Knowledge about the mature functioning of a perceptual competence, as well as knowledge about its developmental course, constrains the selection of viable explanations, but cannot produce a unique interpretation. This goal is pursued through the implementation of an iterative strategy in which competing interpretations are tested until only one plausible alternative remains. A series of experiments investigating infants' sensitivity to biomechanical motions are reviewed as a way of illustrating how this methodology is operationalized.     

Understanding collision dynamics

In two experiments we investigated people's ability to judge the relative mass of two objects involved in a collision. It was found that judgments of relative mass were made on the basis of two heuristics. Roughly stated, these heuristics were (a) an object that ricochets backward upon impact is less massive than the object that it hit, and (b) faster moving objects are less massive. A heuristic model of judgment is proposed that postulates that different sources of information in any event may have different levels of salience for observers and that heuristic access is controlled by the rank ordering of salience. It was found that observers ranked dissimilarity in mass on the basis of the relative salience of angle and velocity information and not proportionally to the distal mass ratio. This heuristic model was contrasted with the notion that people can veridically extract dynamic properties of motion events when the kinematic data are sufficient for their specification.