Stimulus dimensionality effects in mental rotation

Do 3-dimensional (3-D) figures require more time to rotate mentally than do 2-dimensional (2-D) figures? This question was examined in 2 experiments incorporating 15 2-D and 15 3-D stimuli. For 3-D stimuli, block figures were used of the type used by R. N. Shepard and J. Metzler in their classic studies. For 2-D stimuli, block figures were also used, but with all cubes in a single plane, resulting in 2-D and 3-D figures matched on surface features. Three-D figures elicited steeper slopes than did 2-D figures, supporting the view that the mental rotation of visual representations is sensitive to stimulus dimensionality. The authors summarize the results of several mental rotation studies that investigated stimulus dimensionality and suggest that the evidence across studies is consistent with the present finding. They discuss 2 plausible loci for the dimensionality effect in S. M. Kosslyn's (1980) theory of mental imagery.     

Reference frames in mental rotation.

Four experiments are reported that investigate whether images or reference frames are transformed during a mental rotation task. In all experiments a display of four identical letters (P1) was presented at either +90° or –90° from upright, and subjects had to decide whether the letters were normal or mirror-image reflections. A single letter (P2) was then presented 100 ms later in a variable orientation with the same task instructions. Reaction times to P2 were assessed to determine whether an image of P2 was rotated to upright or whether an internal reference frame was rotated into congruence with P2 from the orientation of P1. The results as a whole suggest that transformations of P2 can be initiated either relative to upright or relative to the orientation of P1. They further indicate that the probability of using each reference orientation can be changed by procedural variations. The findings are most parsimoniously interpreted as suggesting that mental rotation involves the transformation of reference frames rather than the transformation of template-like representations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Long-term memory and mental rotation.

Performance of 45 undergraduates on a long-term memory mental rotation paradigm was investigated in 5 experiments and compared with performance in a standard (simultaneous presentation) short-term paradigm. Two related findings emerged: (a) a substantial reduction in RT slope in a "memory" version of the "mental rotation" paradigm and (b) evidence from "fold point" analyses to suggest individualized strategies by Ss in the memory condition. Both of these findings have theoretical and methodological relevance to questions about the interplay of theory and methodology in this research area. (French abstract) (24 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Does mental rotation require central mechanisms?

Four reaction time experiments examined the mental rotation process using a psychological refractory period paradigm. On each trial, participants made speeded responses to both a tone (S?) and a rotated letter (S?), presented with varying stimulus onset asynchronies (SOAs). If mental rotation of the stimulus letter can proceed while central mechanisms are busy with S?, then the effect of orientation should decrease substantially with decreasing SOA. Contrary to these predictions, the effect of orientation was nearly constant across SOAs, suggesting that mental rotation cannot effectively proceed without help from central mechanisms. These results support the conclusion that mental rotation requires access to a single-channel mechanism and must therefore be performed serially with other operations requiring the same mechanism. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The effect of the duration of mental work on problem solving in mental rotation

Effect of sustained mental work on the first stage of mental rotation was studied by the method of intracortical interaction. It was revealed that during sustained mental work the zone of the high level of connections in the alpha-band was considerably reduced due to an increase of specificity, rationality of thinking. In the beta-band the zone of the high connection level moved from the central and parietal areas to the anterior regions because of a switch of intention of the mental work from the spatial analysis to the quick verbalization of the response. Tired subjects in search for a word for the response did not fulfil the spatial analysis of the pictures. Subjects with high working ability searched for the verbal response on the basis of mental operations with images, that turned to be optimal for the mental rotation task solving.     

A hemispheric division of labor aids mental rotation.

In the present study, we investigated whether a hemispheric division of labor is most advantageous to performance when lateralized inputs place unequal resource demands on the left and right cerebral hemispheres. In each trial, participants decided whether 2 rotated letters, presented either in the same visual field (within-field trials) or in opposite visual fields (across-field trials), were both of normal orientation, or whether one was normal and the other was mirror-reversed. To discriminate a letter's orientation, one must rotate the letter to the upright position. Therefore, we manipulated whether the two letters imposed similar or dissimilar demands on cognitive resources by varying the number of degrees that each letter needed to be rotated to reach the upright position. As predicted, in 2 experiments we found that the across-field advantage increased as the number of degrees each letter needed to be rotated became more dissimilar. These findings support a current model of hemispheric interactions, which posits that an unequal hemispheric distribution of cognitive load allows the cerebral hemispheres to take the lead for different aspects of cognitive processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Age differences in the speed of mental rotation.

66 Ss in 4 age groups (mean ages 20.9, 32.4, 50.9, and 63.3 yrs) participated in a mental rotation task for 4 consecutive days. ANOVAs revealed significant age differences in the linear function relating median RT to degrees of rotation: Older Ss had higher intercepts and higher slopes. There were no significant age differences in error rates. Practice reduced slopes and intercepts for all groups, but it neither eliminated nor systematically reduced age differences in mental rotation performance. Mental rotation slopes and intercepts were significantly correlated with performance on the Figures subtest of the Primary Mental Abilities Test but not the Vocabulary subtest of the Nelson-Denny Reading Test. Results point toward age changes in the speed of spatial information processing that may contribute to age changes in performance on tests of spatial ability. (32 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A rotation aftereffect changes both the speed and the preferred direction of mental rotation.

Three experiments are reported that replicate and extend the finding of M. C. Corballis and R. McLaren (1982) regarding the interaction between mental rotation and the rotation aftereffect. In Experiment 1, participants saw tilted characters and made the usual parity judgment. In Experiment 2, participants were explicitly instructed to rotate the characters mentally into one direction or the other. In Experiment 3, participants had to report the direction into which they had mentally rotated. In all experiments, the function relating RT to the rotational angle was influenced by the aftereffect. RT was accelerated if the mental rotation was congruent with the aftereffect and decelerated if it was incongruent. A strategic change of direction of the mental rotation accounted only for some portion of this effect. The major portion has to be attributed to a direct interaction of two movements. The data suggest that the speed of the aftereffect combines with the speed of the mental rotation and, therefore, that imagery and perception share 1 representational medium. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The relationship between mental rotation and representational momentum.

Two experiments explored a possible relationship between mental rotation and representational momentum, a task in which participants were asked to remember an object's position following a sequence of images implying motion. Typically, participants misremember the position as distorted forward along the implied trajectory. If representational momentum relies on mental imagery, the magnitude of memory distortion in a representational momentum task should be positively correlated with the rate of mental rotation. As predicted, faster mental rotation rates and larger memory distortions for object position were observed for rotational axes aligned with the viewers' coordinate system. In addition, participants with slower mental rotation rates produced smaller memory distortions in the implied-event task. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Mental rotation, mental representation, and flat slopes

The "mental rotation" literature has studied how subjects determine whether two stimuli that differ in orientation have the same handedness. This literature implies that subjects perform the task by imagining the rotation of one of the stimuli to the orientation of the other. This literature has spawned several theories of mental representation. These theories imply that mental representations cannot be both orientation-free and handedness-specific. We present four experiments that demonstrate the contrary: mental representations can be both orientation-free and handedness-specific. In Experiment 1 we serendipitously discovered a version of R. N. Shepard and J. Metzler's (1971) "mental rotation" task in which subjects accurately discover the handedness of a stimulus without using "mental rotation," i.e., in which reaction time to compare the handedness of two forms is not a function of the angular disparity between the two forms. In Experiment 2 we generalize this finding to different experimental procedures. In Experiment 3 we replicate this finding with a much larger group of subjects. In Experiment 4 we show that when we preclude the formation of an orientation-free representation by never repeating a polygon, subjects carry out the handedness comparison task by performing "mental rotation."     

Can mental rotation occur before the dual-task bottleneck?

The effect of character disorientation on mirror–normal judgments was found to be partially attenuated with increasing task overlap with a preceding tone-frequency discrimination judgment. These results suggest that orientation-sensitive processing, used to prepare disoriented stimuli for mirror–normal discrimination, can be initiated and proceed in parallel with mental activities required for a tone-frequency discrimination task. The attenuation indicates that at least some of the orientation effect on mirror–normal discriminations had its locus prior to the dual-task processing bottleneck. The possibility that the partial attenuation of the orientation effect was due to attenuation of the effect of orientation on character identification, but not on the mental rotation required for mirror–normal judgments, was examined and rejected. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of stimulus complexity on mental rotation rate of polygons.

Both spatial and propositional theories of imagery predict that the rate at which mental images can be rotated is slower the more complex the stimulus. Four experiments (three published and one unpublished) testing that hypothesis found no effect of complexity on rotation rate. It is argued that despite continued methodological improvements, subjects in the conditions of greater complexity may have found it sufficient to rotate only partial images, thereby vitiating the prediction. The two experiments reported here are based on the idea of making the discriminative response sufficiently difficult so as to force the rotation of complete images. The first one scaled the similarity between standard polygons and certain systematically mutated versions. From the ratings so obtained, two levels of perceived similarity, high and low, were defined and served as separate conditions in a response-time, image rotation experiment. The second experiment tested the complexity hypothesis by examining the effect of similarity on rotation rates and its interaction with levels of complexity. The results support the complexity hypothesis, but only for the highly similar stimuli. Rotation times were also generally slower for high as compared with low similarity. It is argued that these results arise because subjects rotate incomplete images when the stimuli are not very similar. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Reliance on visual imagery and its relation to mental rotation

The relationship of habitual use of visual imagery and mental rotation was investigated. Reliance on Visual Imagery scores were used to define subjects as high frequency or low frequency visualizers. During the mental rotation task, subjects indicated if a pair of 2-dimensional stimulus figures displayed on a computer screen were identical or mirror-images. Figures on the right were rotated in relation to those on the left by 0, 60, 120, or 180 degrees. Data supported the prediction that subjects who report high use of imagery would perform the task with greater accuracy (z = 1.97, p < .05) than subjects who reported low use. The imagery groups did not differ in response latency (z = .91, p < .36). A comparison of performance on Trials 1 to 24 with performance on Trials 115-138 indicated a learning effect in both accuracy (z = 7.58, p < .01) and latency (z = 9.72, p < .01) for all subjects.     

Frames and images: Sequential effects in mental rotation.

Recent studies have shown that response time in mental rotation increases with the angular deviation between the current and preceding stimuli, suggesting a frame rotation process in which the intrinsic frame of the previous stimulus is brought into congruence with the coordinates of the current stimulus. In contrast, we show that this process involves image rotation in which the present stimulus is brought into alignment with the orientation of the previous stimulus. Such "backward alignment" succeeds only for shape-preserving sequences (i.e., identical stimuli at different orientations). Four experiments show that the backward alignment process (a) competes with the uprighting process typically found in mental rotation, and the response is determined by the process requiring the shortest rotational path; (b) is related to the tendency to repeat the previous response; (c) is insensitive to the position of the vertical; (d) is indifferent to the representation of the stimulus in long term memory; and (e) is different from the process underlying preparation for a stimulus in a specified orientation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A large sex difference on a two-dimensional mental rotation task.

Mental rotation tests require participants to identify rotated versions of a target stimulus. The Vandenberg Mental Rotations Test depicts rotations in 3-D space and typically yields one of the largest established cognitive sex differences favoring males. It is presently unclear whether this male advantage is related to the nature of rotations depicted in 3-D space or to the high level of difficulty of this task. The present study developed a new test depicting picture plane, or 2-D, rotations. When task difficulty within this 2-D test was varied, a male advantage as large as that seen on the Vandenberg test was found for the difficult component. These findings suggest that processing in 3 dimensions is not a necessary condition for a large sex difference on tests of mental rotation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The roles of stimulus-response compatibility and mental rotation in mirror-image and left-right decisions.

Examined the relative roles of mental rotation and stimulus-response (SR) compatibility in mirror-image and left-right decisions. 15 Ss, aged 19–43 yrs, were shown rotated letters and asked to indicate whether the letters were normal or backward (mirror-image task). Ss were then asked whether a dot would be located to the left or right of each letter if the letter was upright (viewer-centered left-right task) or if the letter was both upright and normal (letter-centered left-right task). The functions relating reaction time (RT) to angular orientation were parallel across the 3 tasks, suggesting that SR compatibility played no role, and that the Ss mentally rotated the letters to the upright in each case. A marked increase in RT to backward letters in the letter-centered task suggested a 2nd rotation in depth to restore the letters to normal. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Large sexual-orientation-related differences in performance on mental rotation and judgement of line orientation tasks.

This study examined the performance of heterosexual and homosexual men and women on 2 tests of spatial processing, mental rotation (MR) and Benton Judgment of Line Orientation (JLO). The sample comprised 60 heterosexual men, 60 heterosexual women, 60 homosexual men, and 60 homosexual women. There were significant main effects of gender (men achieving higher scores overall) and Gender×Sexual Orientation interactions. Decomposing these interactions revealed large differences between the male groups in favor of heterosexual men on JLO and MR performance. There was a modest difference between the female groups on MR total correct scores in favor of homosexual women but no differences in MR percentage correct. The evidence suggests possible variations in the parietal cortex between homosexual and heterosexual persons. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Cognitive coordinate systems: Accounts of mental rotation and individual differences in spatial ability.

Contends that strategic differences in spatial tasks can be explained in terms of different cognitive coordinate systems that Ss adopt. The strategy of mental rotation featured in many recent experiments uses a coordinate system defined by the standard axes of the human visual world (i.e., horizontal, vertical, and depth axes). Several other possible coordinate systems for solving the problems that occur in psychometric tests of spatial ability are examined. One alternative strategy uses a coordinate system defined by the demands of each test item, resulting in mental rotation around arbitrary, task-defined axes. Another strategy uses a coordinate system defined exclusively by the objects, producing representations invariant with the objects' orientation. Three experiments with 31 university students were conducted to assess differences in strategies used by Ss with high or low spatial ability in cube comparison and Shepard-Metzler (R. Shepard and J. Metzler; see record 1972-28060-001) rotation tasks. Two computer simulation models based on Ss' performance patterns are described. It is suggested that Ss high in spatial ability are faster in their manipulation processes and more flexible in adopting cognitive coordinate systems than their low-ability counterparts. (61 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Response preparation begins before mental rotation is finished: evidence from event-related brain potentials

Behavioral data (response time (RT) and accuracy) and psychophysiological data (event-related brain potentials of ERPs, and lateralized readiness potential or LRP) were studied in an experiment in which rotated alphanumeric characters were presented normally or mirror-reversed. In half of the trials, character classification (letter versus digit) determined whether or not the response was to be executed (go versus nogo) and parity determined the responding hand. In the other half, classification determined the responding hand and parity determined go versus nogo. LRP data indicated that response preparation occurred before mental rotation was finished. These data contradict strictly sequential discrete models of information processing and suggest continuous flow of information.