When One Plus One Equals Three: The Role of Relationships and Context in Community Research

This paper explores the role of relationships within and between the community of the researchers and the community of the research participants, as they relate to qualitative, community psychology research. Although relationships are salient to all research, their role is particularly prominent in qualitative research, in which a closer rapport is established between researcher and research participant than in quantitative research, and the impact of both sides of this interaction on the research process is acknowledged. Instead of merely looking at the community and relationships of the participants, the usual focus of research, this paper also explores the often-overlooked community and relationships of the researchers and then goes on to look at the impact on the research process of the interaction of these two separate communities. This inside story, while seldom explicitly explored or articulated, has implications for community research in general and particularly for applied research.     

Functional equivalence of spatial representations derived from vision and language: evidence from allocentric judgments

Past research (e.g., J. M. Loomis, Y. Lippa, R. L. Klatzky, & R. G. Golledge, 2002) has indicated that spatial representations derived from spatial language can function equivalently to those derived from perception. The authors tested functional equivalence for reporting spatial relations that were not explicitly stated during learning. Participants learned a spatial layout by visual perception or spatial language and then made allocentric direction and distance judgments. Experiments 1 and 2 indicated allocentric relations could be accurately reported in all modalities, but visually perceived layouts, tested with or without vision, produced faster and less variable directional responses than language. In Experiment 3, when participants were forced to create a spatial image during learning (by spatially updating during a backward translation), functional equivalence of spatial language and visual perception was demonstrated by patterns of latency, systematic error, and variability.     

Use of cognitive versus perceptual heading during imagined locomotion depends on the response mode

Three experiments investigated whether the systematic errors previously observed in a triangle-completion task were caused by failures to form and update a cognitive heading or by use of perceived heading (even though an updated cognitive heading was available) during the response. These errors were replicated when participants indicated the origin of triangular paths they had imagined walking by turning their bodies toward the origin, but not when they responded verbally. The results indicate that participants are capable of updating their cognitive heading using imagined movements and suggest that the systematic errors previously observed were a result of the strong attachment of responses such as turns to a perceptual representation of the physical body.     

Dissociation between location and shape in visual space

There are often large perceptual distortions of shapes lying on the ground plane, even in well-lit environments. These distortions occur under conditions for which the perception of location i saccurate. Four hypotheses are considered for reconciling these seemingly paradoxical results, after which 2 experiments are reported that lend further support to 1 of them--that perception of shapeand perception of location are sometimes dissociable. The 2 experiments show that whereas perception of location does not depend on whether viewing is monocular or binocular (when other distance cues are abundant), perception of shape becomes more veridical when viewing is binocular. This means that perception of shape is not fully constrained by the perceived locations of the vertices that define the shape.     

Active control of locomotion facilitates nonvisual navigation

In some navigation tasks, participants are more accurate if they view the environment beforehand. To characterize the benefits associated with visual previews, 32 blindfolded participants were guided along simple paths and asked to walk unassisted to a specified destination (e.g., the origin). Paths were completed without vision, with or without a visual preview of the environment. Previews did not necessarily improve nonvisual navigation. When previewed landmarks stood near the origin or at off-path locations, they provided little benefit; by contrast, when they specified intermediate destinations (thereby increasing the degree of active control), performance was greatly enhanced. The results suggest that the benefit of a visual preview stems from the information it supplies for actively controlled locomotion. Accuracy in reaching the final destination, however, is strongly contingent upon the destination's location during the preview.     

Is the anisotropy of perceived 3-D shape invariant across scale?

A number of studies have resulted in the finding of a 3-D perceptual anisotropy, whereby spatial intervals oriented in depth are perceived to be smaller than physically equal intervals in the frontoparallel plane. In this experiment, we examined whether this anisotropy is scale invariant. The stimuli were L shapes created by two rods placed flat on a level grassy field, with one rod defining a frontoparallel interval, and the other, a depth interval. Observers monocularly and binocularly viewed L shapes at two scales such that they were projectively equivalent under monocular viewing. Observers judged the aspect ratio (depth/width) of each shape. Judged aspect ratio indicated a perceptual anisotropy that was invariant with scale for monocular viewing, but not for binocular viewing. When perspective is kept constant, monocular viewing results in perceptual anisotropy that is invariant across these two scales and presumably across still larger scales. This scale invariance indicates that the perception of shape under these conditions is determined independently of the perception of size.     

Visually perceived location is an invariant in the control of action

We provide experimental evidence that perceived location is an invariant in the control of action, by showing that different actions are directed toward a single visually specified location in space (corresponding to the putative perceived location) and that this single location, although specified by a fixed physical target, varies with the availability of information about the distance of that target. Observers in two conditions varying in the availability of egocentric distance cues viewed targets at 1.5, 3.1, or 6.0 m and then attempted to walk to the target with eyes closed using one of three paths; the path was not specified until after vision was occluded. The observers stopped at about the same location regardless of the path taken, providing evidence that action was being controlled by some invariant, ostensibly visually perceived location. That it was indeed perceived location was indicated by the manipulation of information about target distance—the trajectories in the full-cues condition converged near the physical target locations, whereas those in the reduced-cues condition converged at locations consistent with the usual perceptual errors found when distance cues are impoverished.     

On the tangibility of letters and braille

Braille characters and letters were presented to the senses of touch and vision of sighted observers. The optical stimuli were subjected to low-pass spatial filtering to the degree that visual spatial resolution closely matched tactile spatial resolution(re the size of characters presented). In one experiment, three sets of braille characters and five sets of Roman letters, varying in typography, were presented as stimuli. The variations in tangibility and legibility across the eight character sets were highly correlated (r =.98). In a second experiment, braille characters and letters were varied in size. The psychometric functions relating tangibility and legibility to character size were similar in both shape and position along the abscissa. The congruence of tangibility and legibility for these conditions, in which the senses were matched in spatial resolution, supports the idea that braille characters are more tangible by virtue of their greater distinctiveness after the low-pass spatial filtering of cutaneous processing.     

A lateral masking effect in tactile and blurred visual letter recognition

In a letter recognition task in which the letters were presented temporally across two columns of a vibrotactile array, the masking effects of added columns of steady vibrotactile stimulation were investigated. The primary variable studied was the spatial separation between the masking columns and the letter-carrying columns. The results indicate a spatially dependent masking effect which is independent of the tactile masking associated with mask onset. A comparable masking effect was obtained with visual letter recognition using the same relative stimulus configurations viewed under conditions of optical blurring. An interpretation of the tactile masking is offered in terms of the limited spatial resolution of the cutaneous sense.     

Tactile letter recognition under different modes of stimulus presentation

Block capital letters were displayed to experienced and inexperienced Ss, using a 20 x 20 matrix of vibratory tactors placed against the back. In two separate experiments, a total of five modes of stimulus presentation, three of them employing a linear scanning slit, were studied. The poorest method, stationary flashing of the letter, allows performance that is well above chance, implying that a purely spatial presentation does convey information. Performance is improved when the letter is moved horizontally across the display. The best performance is achieved when the amount of simultaneous stimulation is limited by using a linear scanning slit. In one method, the letter moves behind a stationary slit, with the result that its horizontal dimension is portrayed only in time. In the other two methods, the scanning slit moves across the stationary letter, portraying the letter both in time and in space. The results of all five display modes indicate that Ss can use whichever representation, spatial or temporal, is available, although patternings which most closely approximate sequential tracing by a single moving point lead to the highest recognition accuracy. We interpret these results in terms of the limited spatial resolution of the cutaneous sense. While the perception of a letter presented in either full-field condition is limited by the spatial resolution, the best measure being the two-point limen, the perception of a letter traced sequentially is limited by the localization acuity of the cutaneous sense, the best measure being the “error of localization,” which is known to be considerably smaller than the two-point limen. Inasmuch as the slit methods of presentation are a compromise between simultaneous and sequential display, letter-recognition accuracy is better with slit presentation than with the corresponding full-field mode of display.