Social effects on reference frame selection

Psychonomic Bulletin & Review - The presence of another person in a spatial scene has been shown to induce spontaneous perspective taking. This investigation presents two experiments exploring...     

The reference frame of figure-ground assignment

Figure-ground assignment involves determining which visual regions are foreground figures and which are backgrounds. Although figure-ground processes provide important inputs to high-level vision, little is known about the reference frame in which the figure's features and parts are defined. Computational approaches have suggested a retinally based, viewer-centered reference frame for figure-ground assignment, but figural assignment could also be computed on the basis of environmental regularities in an environmental reference frame. The present research used a newly discovered cue, lower region, to examine the reference frame of figure-ground assignment. Possible reference frames were misaligned by changing the orientation of viewers by having them tilt their heads (Experiments 1 and 2) or turn them upside down (Experiment 3). The results of these experiments indicated that figure-ground perception followed the orientation of the viewer, suggesting a viewer-centered reference frame for figure-ground assignment.     

Functional influences on orienting a reference frame

Spatial relational terms like above are defined with respect to a reference frame. Reference frames are imposed on reference objects and define the space in which to search for a located object. Reference frames have a number of parameters that must be set during spatial term assignment, including origin, scale, and orientation. Previous research has shown that a functional relationship between objects in the scene influences the selection of a reference frame (Carlson-Radvansky & Radvansky, 1996). However, because this work operated at the level of the reference frame, generalizing across various spatial terms, it is unclear how function had its influence. One possibility is that function influences how the parameters of a reference frame are set. Consistent with this idea, Carlson-Radvansky, Covey, and Lattanzi (1999) showed an influence of function on where the origin of a reference frame was imposed. The present paper demonstrates that function also influences how the orientation of the axes of a reference frame is set. The implications for setting multiple parameters of a reference frame are discussed.     

A case of a dual frame of reference.

It is demonstrated that observers may relate to two parts of the same object by using two different frames of reference. Subjects were asked to indicate directions within a model of a hallway in which signs were posted on a single prism. The majority of subjects interpreted a sign frontally facing them as indicating the direction which is ahead of them, yet they interpreted an adjacent sign that was slanted with respect to the frontal plane as indicating a direction which is at the same side of the line of sight as the sign is. This manifests a mixture of an egocentric and an object-centred frame of reference, that is reminiscent of the mixture of local spatial interpretations in impossible pictures. It is suggested that frames of reference are not necessarily unique in a given percept, and that they are not derived from a global computation.     

Haptic mental rotation revisited: multiple reference frame dependence

The nature of reference frames involved in haptic spatial processing was addressed by means of a haptic mental rotation task. Participants assessed the parity of two objects located in various spatial locations by exploring them with different hand orientations. The resulting response times were fitted with a triangle wave function. Phase shifts were found to depend on the relation between the hands and the objects, and between the objects and the body. We rejected the possibility that a single reference frame drives spatial processing. Instead, we found evidence of multiple interacting reference frames with the hand-centered reference frame playing the dominant role. We propose that a weighted average of the allocentric, the hand-centered and the body-centered reference frames influences the haptic encoding of spatial information. In addition, we showed that previous results can be reinterpreted within the framework of multiple reference frames. This mechanism has proved to be ubiquitously present in haptic spatial processing.     

An egocentric frame of reference in implicit motor sequence learning

We investigated which frame of reference is evoked during implicit motor sequence learning. Participants completed a typical serial reaction time task. In the first experiment, we isolated egocentric and allocentric frames of reference and found that learning was solely in an egocentric reference frame. In a second experiment, we isolated hand-centered space from other egocentric frames of reference. We found that for a one-handed sequencing task, the sequence was coded in an egocentric reference frame but not a hand-centered reference frame. Our results are restricted to implicit learning of novel sequences in the early stages of learning. These findings are consistent with claims that the neural mechanisms involved in motor skill learning operate in egocentric coordinates.     

地面参照框架形成的连续表面整合加工假说

地面参照框架是空间知觉的重要基础, 连续表面整合加工(SSIP)假说首次对其形成过程做出了推测, 将这一科学问题的研究向纵深推进, 开辟了一个新的研究领域。SSIP假说的核心观点及其相关证据包括地面的表征原理、整合条件和表征结果三个方面, 得到了大量研究的支持。未来研究需结合基于过程检验的技术手段, 直接探查地面参照框架的形成机制, 关注高级认知过程的作用, 并可考虑其在国防上的应用。     

Change of reference frame for tactile localization during child development

Temporal order judgements (TOJ) for two tactile stimuli, one presented to the left and one to the right hand, are less precise when the hands are crossed over the midline than when the hands are uncrossed. This ‘crossed hand’ effect has been considered as evidence for a remapping of tactile input into an external reference frame. Since late, but not early, blind individuals show such remapping, it has been hypothesized that the use of an external reference frame develops during childhood. Five‐ to 10‐year‐old children were therefore tested with the tactile TOJ task, both with uncrossed and crossed hands. Overall performance in the TOJ task improved with age. While children older than 5½ years displayed a crossed hand effect, younger children did not. Therefore the use of an external reference frame for tactile, and possibly multisensory, localization seems to be acquired at age 5.     

Spatial egocentrism and the effect of an alternate frame of reference

The present study contrasted two possible explanations of spatial egocentrism in spatial perspective tasks. By one account children's judgments in perspectivetaking tasks are based on relations between the self (ego) and the target array. By the second account, children's judgments are based on relations between the target array and the larger spatial field. Sixty children in first, third, and fifth grades (ages 7, 9, and 11 years, respectively) solved both a standard and a modified version of a spatial perspective task. In the modified procedure, subjects observed a model of the experimental room that was rotated to appear as the actual room would appear to a hypothetical viewer. Using the model as an alternative frame of reference improved the performance of subjects in all age groups. In the standard procedure most errors were egocentric. In the modified procedure, subjects showed no systematic egocentric errors for rotations of 90 or 270°. The results supported the hypothesis that systematic egocentric errors are due to subjects realistically maintaining the relation of the array to the immediate spatial field, rather than maintaining the ego-array relation.     

Inhibition within a reference frame during the interpretation of spatial language

Spatial terms such as right are potentially ambiguous because they can refer to different regions of space when defined by competing reference frames (e.g., my right within a relative reference frame versus an object's right within an intrinsic reference frame). In such situations, previous research has suggested that multiple reference frames are initially activated, followed by inhibition of the reference frame that is not ultimately selected to define the spatial term. Reference frames are complex multi-component representations, raising the question of exactly which components of the non-selected frame are inhibited. It is possible that the whole frame may be inhibited, including all axes and endpoints, or that only select endpoints and axes may be inhibited. Three experiments conducted using a negative priming paradigm revealed that only certain components of the non-selected reference frame were inhibited, consistent with the idea that some axes are privileged. These results also suggest that the components of a reference frame can be independently accessed. Implications for representing and accessing spatial information are discussed.     

Visual working memory retains movement information within an allocentric reference frame

What frame of reference do we use to remember observed movements? One possibility is that visual working memory (VWM) retains movement information using a retinotopic frame of reference: A coordinate system with respect to the retina that retains view-dependent information. Alternatively, VWM might retain movement information using an allocentric frame of reference: A coordinate system with respect to the scene that retains view-invariant information. To address this question, I examined whether VWM retains view-dependent or view-invariant movement information. Results show that (1) observers have considerable difficulty remembering from which viewpoints they observed movements after a few seconds' delay, and (2) the same number of movements can be retained in VWM whether the movements are encoded and tested from the same viewpoint or from different viewpoints. Thus, movement representations contain little to no view-dependent information, which suggests that VWM uses an allocentric reference frame to retain movement information.     

Egocentric reference frame bias in the palmar haptic perception of surface orientation

The effect of egocentric reference frames on palmar haptic perception of orientation was investigated in vertically separated locations in a sagittal plane. Reference stimuli to be haptically matched were presented either haptically (to the contralateral hand) or visually. As in prior investigations of haptic orientation perception, a strong egocentric bias was found, such that haptic orientation matches made in the lower part of personal space were much lower (i.e., were perceived as being higher) than those made at eye level. The same haptic bias was observed both when the reference surface to be matched was observed visually and when bimanual matching was used. These findings support the conclusion that, despite the presence of an unambiguous allocentric (gravitational) reference frame in vertical planes, haptic orientation perception in the sagittal plane reflects an egocentric bias.     

Coursework selection: A frame of reference approach using structural equation modelling

Background. Choice behaviour has far‐reaching consequences on students' educational careers. Previous models on course selection for example, the model of achievement‐related choices ( Wigfield & Eccles, 2000 ) and of self‐efficacy theory ( Bandura, 1997 ), stress the importance of ability perceptions (self‐concept of ability) as major determinants of choice. Aim. This article suggests a model of course selection, which assumes that comparisons within an internal frame of reference (as proposed by Marsh, 1986 , for the association between achievement and self‐concepts) can also be applied to the association between self‐concepts and course selection. It is therefore hypothesized that course selection is not only positively influenced by the self‐concept with respect to the corresponding subject, but also negatively with respect to alternative subjects. Moreover, it should be tested whether the effects of previous achievement on course selection are completely mediated by the self‐concepts. Sample. These assumptions were empirically tested using a sample of 296 students from secondary school classes, who were specializing in, for example, chemistry or biology in the following school term. Method. Self‐concepts and course selection were assessed via questionnaire. The postulated models were tested using a structural equation modelling approach for ordinal variables. Results. The core assumption, that course selection is determined by dimensional comparisons, was supported by significant negative paths from self‐concepts on the selection of non‐corresponding subjects. Furthermore, the effects of previous achievement on selection were completely mediated by self‐concepts. Conclusion. Previous models of choice behaviour should be extended, by considering not only the selected alternatives, but also the unselected ones. The finding that the influence of achievement on choice is completely mediated by self‐concepts, demonstrates that subjective interpretations of previous achievement determine subsequent behaviour.     

Change of a frame of reference with velocity in visual motion perception

The present study examined how a frame of reference was affected by velocity. This question was examined with respect to a system consisting of two points: one moved rectilinearly with constant velocity, and the other moved on a track in the shape of a cycloid (defined as the movement of two points—one on the hub and the other on the rim of a rolling wheel). The results indicated that (1) a frame of reference in which the centroid of the total picture was stationary was chosen mainly in a low-velocity range (0.1–0.7 deg/sec), (2) a frame of reference in which a picture point moved rectilinearly was chosen mainly in a medium-velocity range (0.8–40.0 deg/sec), and (3) an absolute coordinate system was chosen mainly in a high-velocity range (>40.0 deg/sec). The current evidence and other findings seem to be consistent with the idea that groups of neurons related to the three frames of reference are independent of one another, that the velocity ranges of the groups of neurons roughly overlapped each other, and that the most salient frame of reference is chosen (i.e., exclusion principle in choice of a frame of reference).