Object and spatial imagery: distinctions between members of different professions

In the current research, we took a new approach to examining individual differences in mental imagery that relied on a key distinction regarding visual imagery, namely the distinction between object and spatial imagery, and further examined the ecological validity of this distinction. Object imagers consistently prefer to construct colorful, pictorial, high-resolution images of individual objects and scenes, and spatial imagers prefer to use imagery to schematically represent spatial relations among objects and can efficiently perform complex spatial transformations. To examine the ecological validity of the object versus spatial imager distinction, we examined the object and spatial imagery preferences and skills of groups of professionals.Visual artists, scientists, architects, and humanities professionals completed two types of imagery tests: spatial imagery tests assessing abilities to process spatial relations and perform spatial transformations, and object imagery tests assessing abilities to process literal appearances of objects in terms of color, shape, and brightness. A clear distinction was found between scientists and visual artists: Visual artists showed above average object imagery abilities but below average spatial imagery abilities; whereas, scientists showed above average spatial imagery abilities but below average object imagery abilities. Visual artists tended to be object imagers, and scientists tended to be spatial imagers. Thus, even though both groups use visual imagery extensively in their work, they in fact tended to excel in only one type of imagery.Furthermore, we interviewed the groups of professionals about imagery characteristics and imagery processes that they typically use when work, we had them interpret kinematics graphs and abstract art, and we monitored their eye-movements as they engaged in various perception and imagery tasks. The data revealed various qualitative differences between the professional groups. Both visual artists and scientists reported using imagery in their work. However, visual artists preferred to use object imagery, but scientists preferred to use spatial imagery for their work. Humanities professionals, however, reported less use of imagery. Additionally, visual artists reported that their images were more likely to come as a whole, but scientists reported that their images were generated part-by-part. Visual artist’s images were more persistent, less intentional, and had multiple meanings as compared to scientist’s images. Furthermore, visual artists and scientists interpreted kinematics graphs and abstract art qualitatively differently. Visual artists tended to interpret graphs literally (graphs-as-pictures), but scientists tended to interpret graphs schematically, in abstract way. However, visual artists tended to interpret the abstract art as abstract representations, but scientists tended to interpret abstract art literally, in a concrete way.The finding that professional domain, where work involves extensive use of object or spatial imagery, differentially predicted object and spatial imagery abilities and approaches in processing visual information provides ecological validation of the distinction between object and spatial imagers. Furthermore, these results provide support for the idea of a trade-off between object and spatial imagery abilities (i.e., a person being more effective at using one type of imagery and then tending to use this type of imagery more frequently than and at the expense of the other type of imagery).     

Spatial versus object visualizers: A new characterization of visual cognitive style

The visual system processes object properties (such as shape and color) and spatial properties (such as location and spatial relations) in distinct systems, and neuropsychological evidence reveals that mental imagery respects this distinction. The findings reported in this article demonstrate that verbalizers typically perform at an intermediate level on imagery tasks, whereas visualizers can be divided into two groups. Specifically, scores on spatial and object imagery tasks, along with a visualizer-verbalizer cognitive style questionnaire, identified a group of visualizers who scored poorly on spatial imagery tasks but excelled on object imagery tasks. In contrast, a second group of visualizers scored high on spatial imagery tasks but poorly on object imagery tasks. The results also indicate that object visualizers encode and process images holistically, as a single perceptual unit, whereas spatial visualizers generate and process images analytically, part by part. In addition, we found that scientists and engineers excel in spatial imagery and prefer spatial strategies, whereas visual artists excel in object imagery and prefer object-based strategies.     

The relationship between self‐reports of imagery and spatial ability

A puzzling question arising from imagery research is why no relationship has been found between self‐reports of imagery and performance on spatial tests thought to require the use of imagery. To investigate this, spatial ability, measured by performance on two spatial tests, was compared with performance on the Vividness of Visual Imagery Questionnaire (VVIQ; Marks, 1973) and a newly constructed imagery questionnaire. The choice of items and ratings for the new questionnaire was based on Kosslyn's (1980, 1994) theories of the imagery system. Ratings on the new questionnaire consistently correlated significantly with performance on the spatial tests, whereas ratings from the VVIQ did not. The new ratings captured more of the imagery process than ratings of vividness alone, but the largest change depended upon the type of item imagined. Ratings of items of the same type as used on the spatial tests predicted performance on the spatial tests, whereas vividness ratings of items recalled or constructed from long‐term memory did not. Participants can successfully introspect on several different properties of their images, and their ratings do predict performance on tasks thought to require imagery. The large effect of item type raises questions about the predictive value of existing models of the imagery system especially in relation to the role of phenomenological properties of our images.     

Visual-object ability: a new dimension of non-verbal intelligence

The goal of the current research was to introduce a new component of intelligence: visual-object intelligence, that reflects one's ability to process information about visual appearances of objects and their pictorial properties (e.g., shape, color and texture) as well as to demonstrate that it is distinct from visual-spatial intelligence, which reflects one's ability to process information about spatial relations and manipulate objects in space. Study 1 investigated the relationship between performance on various measures of visual-object and visual-spatial abilities, and areas of specialization (visual art, science and humanities). Study 2 examined qualitative differences in approaches to interpreting visual abstract information between visual artists, scientists and humanities/social science professionals. Study 3 investigated qualitative differences in visual-object versus visual-spatial processing by examining how members of different professions generate, transform, inspect, and manipulate visual images. The results of the three studies demonstrated that visual-object ability satisfies the requirements of an independent component of intelligence: (1) it uniquely relates to specialization in visual art; (2) it supports processing of abstract visual-object information; and (3) it has unique quantitative and qualitative characteristics, distinct from those of visual-spatial processing.     

The differential contributions of visual imagery constructs on autobiographical thinking

There is a growing theoretical and empirical consensus on the central role of visual imagery in autobiographical memory. However, findings from studies that explore how individual differences in visual imagery are reflected on autobiographical thinking do not present a coherent story. One reason for the mixed findings was suggested to be the treatment of visual imagery as an undifferentiated construct while evidence shows that there is more than one type of visual imagery. The present study investigates the relative contributions of different imagery constructs; namely, object and spatial imagery, on autobiographical memory processes. Additionally, it explores whether a similar relation extends to imagining the future. The results indicate that while object imagery was significantly correlated with several phenomenological characteristics, such as the level of sensory and perceptual details for past events – but not for future events – spatial imagery predicted the level of episodic specificity for both past and future events. We interpret these findings as object imagery being recruited in tasks of autobiographical memory that employ reflective processes while spatial imagery is engaged during direct retrieval of event details. Implications for the role of visual imagery in autobiographical thinking processes are discussed.     

Object imagery and object identification: object imagers are better at identifying spatially-filtered visual objects

Object imagery refers to the ability to construct pictorial images of objects. Individuals with high object imagery (high-OI) produce more vivid mental images than individuals with low object imagery (low-OI), and they encode and process both mental images and visual stimuli in a more global and holistic way. In the present study, we investigated whether and how level of object imagery may affect the way in which individuals identify visual objects. High-OI and low-OI participants were asked to perform a visual identification task with spatially-filtered pictures of real objects. Each picture was presented at nine levels of filtering, starting from the most blurred (level 1: only low spatial frequencies—global configuration) and gradually adding high spatial frequencies up to the complete version (level 9: global configuration plus local and internal details). Our data showed that high-OI participants identified stimuli at a lower level of filtering than participants with low-OI, indicating that they were better able than low-OI participants to identify visual objects at lower spatial frequencies. Implications of the results and future developments are discussed.     

Eye movements disrupt spatial but not visual mental imagery

It has long been known that eye movements are functionally involved in the generation and maintenance of mental images. Indeed, a number of studies demonstrated that voluntary eye movements interfere with mental imagery tasks (e.g., Laeng and Teodorescu in Cogn Sci 26:207–231, 2002). However, mental imagery is conceived as a multifarious cognitive function with at least two components, a spatial component and a visual component. The present study investigated the question of whether eye movements disrupt mental imagery in general or only its spatial component. We present data on healthy young adults, who performed visual and spatial imagery tasks concurrently with a smooth pursuit. In line with previous literature, results revealed that eye movements had a strong disruptive effect on spatial imagery. Moreover, we crucially demonstrated that eye movements had no disruptive effect when participants visualized the depictive aspects of an object. Therefore, we suggest that eye movements serve to a greater extent the spatial than the visual component of mental imagery.     

Individual differences in visual imagery determine how event information is remembered

Individuals differ in how they mentally imagine past events. When reminiscing about a past experience, some individuals remember the event accompanied by rich visual images, while others will remember it with few of these images. In spite of the implications that these differences in the use of imagery have to the understanding of human memory, few studies have taken them into consideration. We examined how imagery interference affecting event memory retrieval was differently modulated by spatial and object imagery ability. We presented participants with a series of video-clips depicting complex events. Participants subsequently answered true/false questions related to event, spatial, or feature details contained in the videos, while simultaneously viewing stimuli that interfered with visual imagery processes (dynamic visual noise; DVN) or a control grey screen. The impact of DVN on memory accuracy was related to individual differences in spatial imagery ability. Individuals high in spatial imagery were less accurate at recalling details from the videos when simultaneously viewing the DVN stimuli compared to those low in spatial imagery ability. This finding held for questions related to the event and spatial details but not feature details. This study advocates for the inclusion of individual differences when studying memory processes.     

Using Real‐World and Standardized Spatial Imagery Tasks: Convergence,Imagery Realism,and Gender Differences

Can realistic spatial scenarios be used to measure spatial mental imagery? Can people accurately evaluate their spatial imagery? Does gender moderate the relationship between performance on realistic spatial imagery tasks and ratings of imagery realism? Forty‐two female and 31 male undergraduates first rated the realism of their images after reading spatial scenarios based on actual spatial tasks. In phase 2, they solved closely related spatial scenario problems, and then completed the VZ‐2 Paper Folding test. Performance on realistic spatial scenarios predicted performance on the VZ‐2. Men's evaluation of their spatial imagery realism predicted their actual spatial performance, but women's did not. More task experience was positively related to more realistic images and higher scores on the VZ‐2. These results were generally consistent with those found with more artificial stimulus materials, but also demonstrated the importance of considering gender differences in spatial problem strategy and/or rating scale interpretation. Copyright © 2014 John Wiley & Sons, Ltd.     

Speech imagery is not always faster than visual imagery

One approach to the study of mental imagery is to examine the performance characteristics of different forms of mental imagery when used in various tasks. To demonstrate the utility of this functional approach, the use of speech and visual imagery processes in the serial mental rehearsal of common verbal sequences le.g., letters of the alphabet and familiar object arrays (objects found in familiar rooms) was examined in the present experiments. Rehearsal rates and self-reporte were consistent with the hypothesis that mental rehearsal efficiency is a function of the compatibility of characteristics of the rehearsal materials and rehearsal mode. While verbal sequences were rehearsed faster under speech than under visual imagery conditions, object arrays were rehearsed as fast under visual as under speech imagery conditions. In addition, evidence was found that covert verbal rehearsal is faster than overt verbal rehearsal under some circumstances.     

A PET meta‐analysis of object and spatial mental imagery

Neuroimaging studies have described the functional neuroanatomy of mental imagery. Taken separately, specific studies vary in the nature of the task used and are limited by statistical power and sensitivity. We took advantage of a multistudy PET database of 54 subjects acquired in our laboratory to reveal the neural bases of spatial versus object mental imagery tasks. Our first goal was to evaluate to what extent the activated foci elicited by both object and spatial studies overlap. A second aim was to compare activations elicited by spatial imagery tasks to those elicited by object imagery tasks. We also explored applying regression analyses to the relationships between the scores on the Mental Rotations Test (MRT) and changes in regional cerebral blood flow (rCBF) during spatial and object imagery tasks. This meta‐analysis yielded the following observations: (1) both spatial and object imagery tasks shared a common neural network composed of occipitotemporal (ventral pathway) and occipitoparietal (dorsal pathway) regions and also by a set of frontal regions (related to memory); (2) the superior parietal cortex was more strongly implicated during spatial imagery; (3) object imagery specifically engaged the anterior part of the ventral pathway, including the fusiform, parahippocampal, and hippocampal gyrus; (4) object imagery activated the early visual cortex, whereas spatial imagery induced a deactivation of the early visual cortex; (5) blood flow values in some of the regions noted above were positively correlated with scores on the MRT: the higher the subjects performed on the MRT, the more pronounced the rCBF was in these regions. These results may reconcile some of the apparent discrepancies among previous studies concerning the activation of early visual cortex in mental imagery. They also contribute to a better knowledge of the neural bases of object and spatial mental imagery.     

Interference effects demonstrate distinct roles for visual and motor imagery during the mental representation of human action

Four experiments were completed to characterize the utilization of visual imagery and motor imagery during the mental representation of human action. In Experiment 1, movement time functions for a motor imagery human locomotion task conformed to a speed-accuracy trade-off similar to Fitts' Law, whereas those for a visual imagery object motion task did not. However, modality-specific interference effects in Experiment 2 demonstrate visual and motor imagery as cooperative processes when the action represented is tied to visual coordinates in space. Biomechanic-specific motor interference effects found in Experiment 3 suggest one basis for separation of processing channels within motor imagery. Finally, in Experiment 4 representations of motor actions were found to be generated using only visual imagery under certain circumstances: namely, when the imaginer represented the motor action of another individual while placed at an opposing viewpoint. These results suggest that the modality of representation recruited to generate images of human action is dependent on the dynamic relationship between the individual, movement, and environment.     

An age-related view of the role of object and spatial cognitive styles in distance estimation

Distance estimations require identifying characteristics of the object and its spatial surroundings. With the present study, we examined the relationship between visual object and spatial (cognitive) styles and distance estimations in children and adults. Participants were administered the Object-Spatial Imagery Questionnaire (OSIQ) and two distance estimation tasks—one required estimating reach distance (reach task [RT]) from the self and the other required estimating distance between targets (perceptual task[PT]). Overall, our findings indicated that age was the best predictor of estimation for RT and PT tasks, and individuals were more accurate in the task requiring an egocentric frame of reference (RT) compared to tasks that require allocentric judgements (PT). In addition, children had higher ratings on cognitive styles in comparison to adults, but both object and spatial styles only related to RT accuracy in adults. Cognitive styles seem to be associated to distance estimation accuracy, but only when there is a clear preference.     

Multisensory cortical processing of object shape and its relation to mental imagery

Here, we used functional magnetic resonance imaging to investigate the multisensory processing of object shape in the human cerebral cortex and explored the role of mental imagery in such processing. Regions active bilaterally during both visual and haptic shape perception, relative to texture perception in the respective modality, included parts of the superior parietal gyrus, the anterior intraparietal sulcus, and the lateral occipital complex. Of these bimodal regions, the lateral occipital complexes preferred visual over haptic stimuli, whereas the parietal areas preferred haptic over visual stimuli. Whereas most subjects reported little haptic imagery during visual shape perception, experiences of visual imagery during haptic shape perception were common. Across subjects, ratings of the vividness of visual imagery strongly predicted the amount of haptic shape-selective activity in the right, but not in the left, lateral occipital complex. Thus, visual imagery appears to contribute to activation of some, but not all, visual cortical areas during haptic perception.     

Semantic interference from visual object recognition on visual imagery

A new technique for examining the interaction between visual object recognition and visual imagery is reported. The "image-picture interference" paradigm requires participants to generate and make a response to a mental image of a previously memorized object, while ignoring a simultaneously presented picture distractor. Responses in 2 imagery tasks (making left-right higher spatial judgments and making taller-wider judgments) were longer when the simultaneous picture distractor was categorically related to the target distractor relative to unrelated and neutral target-distractor combinations. In contrast, performance was not influenced in this way when the distractor was a related word, when a semantic categorization decision was made to the target, or when distractor and target were visually but not categorically related to one another. The authors discuss these findings in terms of the semantic representations shared by visual object recognition and visual imagery that mediate performance.     

Individual Differences in visual imagery and spatial ability

Spatial ability is generally assumed to involve construction, transformation, and interpretation of mental images. To explore the relationship between spatial ability and both image quality and image process efficiency, 79 subjects performed eight spatial tests, completed three imagery questionnaires, and participated in six laboratory tasks. These laboratory tasks were devised to measure image quality and the efficiency of image generation, image rotation, image scanning, adding and subtracting detail in images, and integration of images. Although ratings of imagery control and vividness were unrelated to spatial test performance, laboratory measures of process efficiency and image quality were strongly related to spatial test performance and weakly related to one another. A structural equation model identified a single spatial factor, Visualization ability, that can be decomposed into unique variance plus a linear combination of measures of image quality and image process efficiency. An interpretation of this model is that successful performance on spatial tests requires maintenance of a high-quality image and efficient image transformation and inspection processes.     

A simulation of visual imagery

This paper describes an operational computer simulation of visual mental imagery in humans. The structure of the simulation was motivated by results of experiments on how people represent information in, and access information from, visual images. The simulation includes a “surface representation,” which is spatial and quasi-pictorial, and an underlying “deep representation,” which contains “perceptual” information encoding appearance plus “propositional” information describing facts about an object. The simulation embodies a theory of how surface images are generated from deep representations, and how surface images are processed when one accesses information embedded in them. The simulation also offers an account of various sorts of imagery transformations.     

A computational framework for attentional object discovery in RGB-D videos

We present a computational framework for attention-guided visual scene exploration in sequences of RGB-D data. For this, we propose a visual object candidate generation method to produce object hypotheses about the objects in the scene. An attention system is used to prioritise the processing of visual information by (1) localising candidate objects, and (2) integrating an inhibition of return (IOR) mechanism grounded in spatial coordinates. This spatial IOR mechanism naturally copes with camera motions and inhibits objects that have already been the target of attention. Our approach provides object candidates which can be processed by higher cognitive modules such as object recognition. Since objects are basic elements for many higher level tasks, our architecture can be used as a first layer in any cognitive system that aims at interpreting a stream of images. We show in the evaluation how our framework finds most of the objects in challenging real-world scenes.     

Category-specific naming and modality-specific imagery

Some attempts to explain category-specific disorders have stressed how different modality knowledge bases (i.e., visual knowledge vs motoric/functional knowledge) may underlie the distinction between living and nonliving things. This study examined 60 normal subjects for the relationship between picture naming in four subcategories (animals, fruit/vegetables, praxic and nonpraxic objects) and imagery vividness in seven modalities. Participants made more nonliving than living errors; and females made more nonliving errors than males. There was a significant correlation between naming of animals and fruits/vegetables and visual imagery vividness; however, this association was also significant for praxic and nonpraxic object naming. There was no evidence of associations between kinesthetic imagery and praxic object naming or gustatory/olfactory imagery and fruit/vegetable naming. These findings accord with the notion of a general association between visual imagery and picture naming, but provide no support for more specific links between modality-specific imagery vividness and naming in different categories.