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.     

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.     

An information-processing approach to attribution of responsibility

The research literature on defensive attribution of responsibility is reviewed within the framework of a nonmotivational information-processing model which proposes that attributed responsibility is a function of the difference between the perceived contingent probability (congruence) of an outcome, given a perpertrator's behavior, and the noncontingent probability (prior expectancy) of that outcome. Results of previous research on effects of the characteristics of outcomes, perpetrator, and victim on responsibility ratings are reinterpreted in terms of the influence these factors have on estimates of congruence and prior expectancy. Secondary analyses of data from a recent study of causal reasoning resulted in a correlation of .78 between attribution of responsibility and a simple additive model of estimated contingent and prior probabilities of an accident.     

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.     

Rorschach-based indices of visual imagery reactivity

A method using a specially developed Rorschach-based procedure was applied in conjunction with a visual imagery technique in evaluating protocols of 40 outpatient subjects. The subjects were divided into Reactor and Nonreactor groups, according to how productive in clinically significant material their responses were in the imagery condition contrasted to a conventional administration of the Rorschach. A scoring method correctly classified 35 of the 40 subjects as being Reactors or Nonreactors. In addition to previously demonstrated utility as a research tool, the method may be used in clinical situations.     

Relationships among measures of visual imagery

As a step toward the development of an objective measure of visualization ability, five tasks which yielded seven separate measures were administered to 74 Ss and intercorrelated. The tasks were: paired associate recall improvement (RI), recognition memory (RM), the Bett's Questionnaire on Mental Imagery (QMI) as revised by Sheehan (1967a, b), a task calling for the production of visual images (PVI) where rated vividness and latency of image attainment were measured, and a task requiring the imagining of emotional scenes (ES) where rated vividness and rated anxiety were measured. The results indicated that although paired associate learning scores per se were related to RM, neither of the memory measures of visualization (RI and RM) were related to any of the other visualization measures. A cluster of intercorrelations was obtained among self-ratings of image vividness on the QMI, PVI and ES tasks. This cluster also included a measure of latency of report of “best image” attainable derived from the PVI task. None of the measures correlated with anxiety ratings on the ES task. These findings were discussed in relation to previous studies and the potential value of the latency measure as an adjunct measure of visualization ability was noted.     

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.     

Fear selectively modulates visual mental imagery and visual perception

Preferences for faces are thought to be the result of either general adaptations for mate selection, and thus influenced by sexual dimorphism, or mechanisms of general information processing and thus nonspecific to faces. If mate choice determines face preference then it should follow that the sex of a face should affect attractiveness judgements. To test this idea we used image morphing to generate three versions of face images: original, opposite sex, and antiface. First we established that the sex of the face was identifiable in our images. We then collected attractiveness ratings for the three face types. We found that attractiveness ratings to the original faces were correlated with, and did not differ significantly between, ratings to the opposite-sex faces. However, ratings for either the original or opposite face types were not correlated with and were significantly lower than ratings to the antifaces. Our findings failed to support the idea that attractiveness is related to sexual dimorphism in faces alone but suggest instead that other more generic factors influence preferences for all faces.     

The influence of visual experience on visual and spatial imagery

Differences are reported between blind and sighted participants on a visual-imagery and a spatial-imagery task, but not on an auditory-imagery task. For the visual-imagery task, participants had to compare object forms on the basis of a (verbally presented) object name. In the spatial-imagery task, they had to compare angular differences on the basis of the position of clock hands on two clock faces, again only on the basis of verbally presented clock times. Interestingly, there was a difference between early-blind and late-blind participants on the visual-imagery and the spatial-imagery tasks: late-blind participants made more errors than sighted people on the visual-imagery task, while early-blind participants made more errors than sighted people on the spatial-imagery task. This difference suggests that, for visual (form) imagery, people use the channel currently available (haptic for the blind; visual for the sighted). For the spatial-imagery task in this study reliance on haptic processing did not seem to suffice, and people benefited from visual experience and ability. However, the difference on the spatial-imagery task between early-blind and sighted people in this study might also be caused by differences in experience with the analogue clock faces that formed the basis for the spatial judgments.     

Eye movements during visual mental imagery

It has long been debated whether eye movements play a functional role in visual mental imagery. A recent paper by Laeng and Teodorescu presents new evidence that eye movements are stored as a spatial index that is used to arrange the component parts correctly when mental images are generated.     

Clinical applications of Rorschach-based visual imagery reactivity

A diverse set of findings from recent research suggests the value of visual imagery techniques in clinical practice.     

How visual imagery interferes with vision.

Mental visual imagery interferes with vision: the Perky (1910) effect. Is the effect optical, sensory, perceptual, attentional, or just a response bias? Acuity was measured (in undergraduates and graduates) using target lines, with and without images (of lines). Optics (fixation, pupil size, accommodation), response bias, global attention (effort; diversion of attention to imagery), perceptual assimilation (target incorporation by imagery) and perceptual masking (of target by imagery) all fail to explain the effect. Foveally, local attention plays a limited role, as the Perky effect in divided attention is half that in focused attention, but this interaction vanishes with extrafoveal targets. Images produce primarily sensory interference, mimicking a reduction in target energy.     

Developmental changes in word recognition: An information-processing account

Two experiments examining developmental changes in the use of context in single word reading are reported. The first experiment investigated how effectively children can access conceptual knowledge and use this to help their word recognition. The results indicated that young readers can on demand direct their attention to semantic information, and this allows them to reap a relatively greater benefit from context than older more skilful readers. The second experiment attempted to clarify the way such use of contextual information might help in the specific case when a child attempts to decode a new word for the first time. Skilled and unskilled readers pronounced pseudohomophonic nonwords faster when they were primed by a semantic context, and the context effect was greater for unskilled readers. The nonword's graphemic similarity to a lexical item was also important.

In general, the results were consistent with Stanovich's (1980) interactive-compensatory model of reading, and they suggest that in learning to read, several already existing stores of information (e.g. auditory, visual and conceptual) are integrated in order to achieve a solution to the word recognition problem.