Two reference frames for visual perception in two gravity conditions

The processing and storage of visual information concerning the orientation of objects in space is carried out in anisotropic reference frames in which all orientations are not treated equally. The perceptual anisotropies, and the implicit reference frames that they define, are evidenced by the observation of 'oblique effects' in which performance on a given perceptual task is better for horizontally and vertically oriented stimuli. The question remains how the preferred horizontal and vertical reference frames are defined. In these experiments cosmonaut subjects reproduced the remembered orientation of a visual stimulus in 1g (on the ground) and in 0g, both attached to a chair and while free-floating within the International Space Station. Results show that while the remembered orientation of a visual stimulus may be stored in a multimodal reference frame that includes gravity, an egocentric reference is sufficient to elicit the oblique effect when all gravitational and haptic cues are absent.     

Perceptual and motor congruency effects in time–space association

It is well established that temporal events are represented on a spatially oriented mental time line from left to right. Depending on the task characteristics, the spatial representation of time may be linked to different types of dimensions, including manual response codes and physical space codes. The aim of the present study was to analyze whether manual response and physical space codes are independent of each other or whether they interact when both types of information are involved in the task. The participants performed a temporal estimation task with two lateralized response buttons in four experiments. In the first experiment, the target stimuli were presented on the left side, at the center, or on the right side of the space, whereas the reference stimuli were always presented centrally. The reverse situation was presented in the second experiment. In the third experiment, both stimuli were presented in opposite spatial positions (e.g., left–right), whereas in the last experiment, both stimuli were presented in the same spatial position (e.g., left–left). In all experiments, perceptual and motor congruency effects were found, but no modulation of the congruency effects was found when both the perceptual and motor components were congruent. The results indicated that physical, spatial, and manual response codes are independent from each other for time–space associations, even when both codes are involved in the task. These results are discussed in terms of the “intermediate-coding” account.     

Selective spatial attention and length representation in normal subjects and in patients with unilateral spatial neglect

The aim of this study was to assess whether perceptual representation along the horizontal axis is affected by hemispace position of the stimulus or by orienting attention to one side. Ten control subjects and 10 right brain damaged patients with left unilateral spatial neglect (USN) were asked to bisect lines of five lengths in three space positions (left, center, right) and under three cueing conditions (no cue, left cue, right cue). Normal controls showed significant displacement of bisection opposite to the side of hemispace presentation and toward the side of cueing. USN patients showed a bisection error toward the right end which increased with lines placed in the left hemispace and decreased with lines placed in the right hemispace and when attention was oriented toward the left side. We conclude that (1) In absence of cues normal subjects tend to overestimate the portions of space closer to their body midline; (2) both normal and USN patients tend to overestimate portions of space that they direct their attention to; (3) USN patients' performance without cueing is consistent with an attentional shift toward the right hemispace implying a gradient of overestimation of the right-most portions of space. A common neural substratum for directing attention and space representation can explain these findings.     

Multisensory cues capture spatial attention regardless of perceptual load

We compared the ability of auditory, visual, and audiovisual (bimodal) exogenous cues to capture visuo-spatial attention under conditions of no load versus high perceptual load. Participants had to discriminate the elevation (up vs. down) of visual targets preceded by either unimodal or bimodal cues under conditions of high perceptual load (in which they had to monitor a rapidly presented central stream of visual letters for occasionally presented target digits) or no perceptual load (in which the central stream was replaced by a fixation point). The results of 3 experiments showed that all 3 cues captured visuo-spatial attention in the no-load condition. By contrast, only the bimodal cues captured visuo-spatial attention in the high-load condition, indicating for the first time that multisensory integration can play a key role in disengaging spatial attention from a concurrent perceptually demanding stimulus.     

Perceptual equivalence of acoustic cues in speech and nonspeech perception

Trading relations show that diverse acoustic consequences of minimal contrasts in speech are equivalent in perception of phonetic categories. This perceptual equivalence received stronger support from a recent finding that discrimination was differentially affected by the phonetic cooperation or conflict between two cues for the /slIt/-/splIt/contrast. Experiment 1 extended the trading relations and perceptual equivalence findings to the /sei/-/stei/contrast. With a more sensitive discrimination test, Experiment 2 found that cue equivalence is a characteristic of perceptual sensitivity to phonetic information. Using “sine-wave analogues” of the /sei/-/stei/stimuli, Experiment 3 showed that perceptual integration of the cues was phonetic, not psychoacoustic, in origin. Only subjects who perceived the sine-wave stimuli as “say” and “stay” showed a trading relation and perceptual equivalence; subjects who perceived them as nonspeech failed to integrate the two dimensions perceptually. Moreover, the pattern of differences between obtained and predicted discrimination was quite similar across the first two experiments and the “say”-“stay” group of Experiment 3, and suggested that phonetic perception was responsible even for better-than-predicted performance by these groups. Trading relations between speech cues, and the perceptual equivalence that underlies them, thus appear to derive specifically from perception of phonetic information.     

语言和情境对具体概念感知运动仿真的影响

具体概念加工中的感知运动仿真是概念表征的核心加工过程。本研究系统探讨了语言因素(语言类型：第一语言和第二语言)和情境因素(知觉情境：空间知觉情境和语义知觉情境)对具体概念加工中感知运动仿真的影响。实验1采用语义相关判断范式探讨了第二语言加工过程中是否存在感知运动仿真, 以及第二语言中的仿真和第一语言中的仿真是否存在差异。研究发现, 第二语言加工中依然存在感知运动仿真, 但是第一语言的感知运动仿真具有一定的优势。实验2采用语义相关判断范式及其变式, 通过2个分实验分别探讨了个体加工概念时空间知觉信息和语义知觉信息对于概念表征过程中感知运动仿真的影响。研究发现, 无论是在较弱的空间信息知觉条件下还是在较浅的语义信息知觉条件下, 具体概念加工过程中都产生了感知运动仿真。本研究的发现弥补了知觉符号理论未对第二语言中的感知运动仿真提出针对性预测的不足, 表明感知运动仿真具有一定的跨语言稳定性。同时, 具体概念加工中的感知运动仿真不受空间信息和语义信息的调节, 这表明感知运动仿真能在一定程度上自动化产生。     

Spatial frequency content of visual imagery

Three experiments employing the McCollough paradigm were conducted to determine the spatial-frequency content of visual imagery. In Experiment 1, large and reliable pattern-contingent color aftereffects were obtained after adaptation to visual imagery. The direction of the aftereffects indicated that subjects were adapting to higher spatial frequencies in their imagery. These results contrast with the data of Experiment 2, which demonstrate that color aftereffects obtained with adaptation to physically present stimuli are mediated by the fundamental spatial frequency components. The magnitude of the imagery-induced aftereffects in Experiment 1 equaled the magnitude of the externally induced aftereffects obtained in Experiment 2 with the same subjects. By blurring the to-be-imaged patterns (Experiment 3), the fundamental Fourier components became the salient perceptual features of the stimuli, and the direction of the imagery-induced aftereffects was reversed from that of Experiment 1, indicating that the spatial frequency content of the imagery had changed from higher to lower frequencies. Under normal viewing conditions, subjects use the higher spatial frequencies associated with the perceptually salient edges of stimuli to construct their images. The results of Experiments 1 and 3 are discussed in light of a current controversy over the nature of information representation in imagery, and it is concluded that support has been obtained for the analog model of visual imagery.     

Spatial representation of pitch height: the SMARC effect

Through the preferential pairing of response positions to pitch, here we show that the internal representation of pitch height is spatial in nature and affects performance, especially in musically trained participants, when response alternatives are either vertically or horizontally aligned. The finding that our cognitive system maps pitch height onto an internal representation of space, which in turn affects motor performance even when this perceptual attribute is irrelevant to the task, extends previous studies on auditory perception and suggests an interesting analogy between music perception and mathematical cognition. Both the basic elements of mathematical cognition (i.e. numbers) and the basic elements of musical cognition (i.e. pitches), appear to be mapped onto a mental spatial representation in a way that affects motor performance.     

Exploring the role of repetition and sensory elaboration in the imagination inflation effect

Two experiments were conducted to examine whether a misattribution of specific characteristics or a misattribution of global familiarity underlies false memories as assessed through imagination inflation. Using the paradigm developed by Goff and Roediger (1998), we found that the proportion of false memories increased with repeated imagination, replicating the imagination inflation effect. False memories developed through imagination were greatest in conditions that forced participants to include sensory detail in their imaginings. Finally, conscious recollection more often accompanied false memories in perceptually detailed imagination conditions, whereas feelings of familiarity more often accompanied false memories in conditions that lacked sensory cues. These results suggest that imagination that contains more perceptual information leads to more elaborate memory representations containing specific characteristics that can be confused with actually performed actions. Confusion based on these representations, as opposed to confusion based on processing fluency, is more likely to lead to false memories.     

Combined effects of perceptual grouping cues on object representation: Evidence from motion-induced blindness

We investigated the combined effects of perceptual grouping cues (proximity and contour closure/proximity and orientation similarity) on object representation, using motion-induced blindness, a phenomenon in which salient visual stimuli perceptually disappear when surrounded by moving patterns. We presented as visual targets two stimuli in which a solid square was embedded in an outlined square. Participants reported whether the targets disappeared independently or simultaneously. The results showed that a relatively high proximity cue (with a 0.2-deg separation between the targets) modulated the perceptions of the independent or simultaneous disappearances of targets, regardless of other grouping cues. The contour closure cue modulated these disappearances in the 0.4- to 0.8-deg separations. Finally, the orientation similarity cue began to modulate these disappearances in the 0.6- to 0.8-deg separations. We suggest that the separation between the visual stimuli modulates the combined effects of perceptual grouping cues on complete object representation.     

情境模型的更新：事件框架依赖假设的进一步证据

采用多指标探测范式, 从客体信息以及活动信息的角度出发, 考察事件框架内外时间、空间转换对情境模型更新的影响。结果发现：在事件框架内, 维度转换并不是情境模型更新的充分条件, 时间转换与终止的活动信息相结合引起情境模型的快速更新, 而空间转换与移除的客体信息相结合引起情境模型的快速更新; 在事件框架外, 维度转换是情境模型更新的充分条件, 维度转换会引起情境模型的更新。研究丰富了事件框架依赖假设。     

Spatial memory in the grey mouse lemur (Microcebus murinus)

Wild animals face the challenge of locating feeding sites distributed across broad spatial and temporal scales. Spatial memory allows animals to find a goal, such as a productive feeding patch, even when there are no goal-specific sensory cues available. Because there is little experimental information on learning and memory capabilities in free-ranging primates, the aim of this study was to test whether grey mouse lemurs (Microcebus murinus), as short-term dietary specialists, rely on spatial memory in relocating productive feeding sites. In addition, we asked what kind of spatial representation might underlie their orientation in their natural environment. Using an experimental approach, we set eight radio-collared grey mouse lemurs a memory task by confronting them with two different spatial patterns of baited and non-baited artificial feeding stations under exclusion of sensory cues. Positional data were recorded by focal animal observations within a grid system of small foot trails. A change in the baiting pattern revealed that grey mouse lemurs primarily used spatial cues to relocate baited feeding stations and that they were able to rapidly learn a new spatial arrangement. Spatially concentrated, non-random movements revealed preliminary evidence for a route-based restriction in mouse lemur space; during a subsequent release experiment, however, we found high travel efficiency in directed movements. We therefore propose that mouse lemur spatial memory is based on some kind of mental representation that is more detailed than a route-based network map. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Mental rotation is not easily cognitively penetrable

When participants take part in mental imagery experiments, are they using their “tacit knowledge” of perception to mimic what they believe should occur in the corresponding perceptual task? Two experiments were conducted to examine whether such an account can be applied to mental imagery in general. These experiments both examined tasks that required participants to “mentally rotate” stimuli. In Experiment 1, instructions led participants to believe that they could reorient shapes in one step or avoid reorienting the shapes altogether. Regardless of instruction type, response times increased linearly with increasing rotation angles. In Experiment 2, participants first observed novel objects rotating at different speeds, and then performed a mental rotation task with those objects. The speed of perceptually demonstrated rotation did not affect the speed of mental rotation. We argue that tacit knowledge cannot explain mental imagery results in general, and that in particular the mental rotation effect reflects the nature of the underlying internal representation and processes that transform it, rather than participants’ pre-existing knowledge.     

Perceiving expressions of emotion: What evidence could bear on questions about perceptual experience of mental states?

What evidence could bear on questions about whether humans ever perceptually experience any of another’s mental states, and how might those questions be made precise enough to test experimentally? This paper focusses on emotions and their expression. It is proposed that research on perceptual experiences of physical properties provides one model for thinking about what evidence concerning expressions of emotion might reveal about perceptual experiences of others’ mental states. This proposal motivates consideration of the hypothesis that categorical perception of expressions of emotion occurs, can be facilitated by information about agents’ emotions, and gives rise to phenomenal expectations. It is argued that the truth of this hypothesis would support a modest version of the claim that humans sometimes perceptually experience some of another’s mental states. Much available evidence is consistent with, but insufficient to establish, the truth of the hypothesis. We are probably not yet in a position to know whether humans ever perceptually experience others’ mental states.     

Meaning structures and mental representations

This paper argues for a distinction between meaning structure and mental representation, and presents the outlines of a theoretical model of their interrelationship. Meaning structures are defined as structures in the human mind/brain which develop as the combined result of genetic predispositions and individual experience, and lead to relatively stable patterns of perceiving, thinking, feeling, behaving, etc. Mental representation is defined as the aspect of mental processes which involves imagining and thinking of things that are not perceptually present. It is suggested that the mind includes a central network of meaning structures (CNMS) for the storage of information, and a number of other subsystems (e.g., perceptual systems, behavioral systems, and a verbal system) for the processing of externally and internally generated information. Against the dual-coding theory, it is argued that there is one code for the long-term storage of information, but several codes for the processing of information. Mental representations are seen as products of activation that is spread from the CNMS to more peripheral systems. The spread of activation from the CNMS to perceptual systems results in mental imagery; when activation spreads to the verbal system the result is conceptual thinking; and when activation spreads to behavioral systems it produces intentions. It is argued that this conceptual model can help to solve some basic theoretical problems that have plagued cognitive psychology.     

Attention: reaction time and accuracy reveal different mechanisms

The authors propose that there are 2 different mechanisms whereby spatial cues capture attention. The voluntary mechanism is the strategic allocation of perceptual resources to the location most likely to contain the target. The involuntary mechanism is a reflexive orienting response that occurs even when the spatial cue does not indicate the probable target location. Voluntary attention enhances the perceptual representation of the stimulus in the cued location relative to other locations. Hence, voluntary attention affects performance in experiments designed around both accuracy and reaction time. Involuntary attention affects a decision as to which location should be responded to. Because involuntary attention does not change the perceptual representation, it affects performance in reaction time experiments but not accuracy experiments. The authors obtained this pattern of results in 4 different versions of the spatial cuing paradigm.     

Perception: The interface between cognition and the external world

In contrast to researchers who emphasize the distinction between perception and cognition it is claimed that the perceptual system is closely intertwined with cognition and with our comprehension of the external world. This claim is supported by evidence for two characteristic features of human information processing. One of these features is the use of mental models. If mental models are assumed to be anchored in the perceptual system it will not be necessary to assume a "little man in the head" who reads off the model. Moreover, perceptually based mental models will provide a referential semantics by anchoring mentally represented concepts in the external world. The other feature is the use of perceptually based perspectives in cognition, such as actor or observer perspectives in social cognition. It is concluded that human beings consistently interact within the real world--also when they are just thinking--and that this becomes possible via perceptual processes.     

Chess players' intake of task-relevant cues

Patterns of chess pieces are important for chess players in storing information in memory-recall tasks. It also may be assumed that these patterns play a central role in the perceptual coding of task-relevant cues. Two perceptual classification experiments were done to test this assumption. Chess-players' intake of task-relevant cues was studied by measuring the reaction times of subjects in counting the minor pieces on the chessboard or searching for checks in the game and in random positions. Surprisingly, there was no interaction between the level of skill and the type of position. In Experiment 3, both a perceptual classification task and a memory-recall task using the same positions were presented to a group of chess players at the same session. In the perceptual classification task, there was no interaction between the level of skill and the type of position, but in the recall task there was strong interaction. The result suggests that the information intake of chess players, in its lowest levels, is not dependent on the learned patterns. The role of the patterns becomes important in defining the information to be looked for, but the patterns are not important in the early-stage perceptual structuring of a position.     

The effects of spatial representation on memory for verbal navigation instructions

Three experiments investigated effects of mental spatial representation on memory for verbal navigation instructions. The navigation instructions referred to a grid of stacked matrices displayed on a computer screen or on paper, with or without depth cues, and presented as two-dimensional diagrams or a three-dimensional physical model. Experimental instructions either did or did not promote a three-dimensional mental representation of the space. Subjects heard navigation instructions, immediately repeated them, and then followed them manually on the grid. In all display and experimental instruction conditions, memory for the navigation instructions was reduced when the task required mentally representing a three-dimensional space, with movements across multiple matrices, as compared with a two-dimensional space, with movements within a single matrix, even though the words in the navigation instructions were identical in all cases. The findings demonstrate that the mental representation of the space influences immediate verbatim memory for navigation instructions.