Early sex differences in spatial skill.

This study investigated sex differences in young children's spatial skill. The authors developed a spatial transformation task, which showed a substantial male advantage by age 4 years 6 months. The size of this advantage was no more robust for rotation items than for translation items. This finding contrasts with studies of older children and adults, which report that sex differences are largest on mental rotation tasks. Comparable performance of boys and girls on a vocabulary task indicated that the male advantage on the spatial task was not attributable to an overall intellectual advantage of boys in the sample. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The influence of spatial ability on gender differences in mathematics college entrance test scores across diverse samples.

The relationship between mental rotation ability and gender differences in Scholastic Aptitude Test-Math (SAT-M) across diverse samples was investigated. Talented preadolescents, college students and high- and low-ability college-bound youths, totaling 760, were administered the Vandenberg Mental Rotation Test. Gender comparisons showed male outperforming female students in both mental rotation and SAT-M for all 3 high-ability groups but not for the low-ability group. For all female samples, mental rotation predicted math aptitude even when SAT-Verbal was entered first into the regression. For male samples, the relationship varied as a function of sample. When mental rotation ability was statistically adjusted for, the significant gender difference in SAT-M was eliminated for the college sample and the high-ability college-bound students. This suggests that spatial ability may be responsible in part for mediating gender differences in math aptitude among these groups. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A Rotation Invariant in 3-D Reaching.

In 3 experiments, the authors investigated changes in hand orientation during a 3-D reaching task that imposed specific position and orientation requirements on the hand's initial and final postures. Instantaneous hand orientation was described using 3-element rotation vectors representing current orientation as a rotation from a fixed reference orientation. The direction of these 3-vectors gives the rotation axis, and the length of the axis gives the rotation magnitude. Hand translation parameters (relative timing of velocity components, trajectory linearity) varied systematically with position and orientation of the target, arm load, and movement velocity. Hand orientation, however, remained constrained to 2-D planar motions in the 3-D space of all possible rotation vectors. Implications of this functional constraint for theories of trajectory formation are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Sexual maturation and spatial ability in college students.

194 female and 80 male undergraduates completed mental rotation and card rotation tests of spatial ability and a vocabulary test. Ss were also asked to indicate on a 5-point rating scale when they reached puberty in relation to others of the same sex. Findings provide evidence that the maturation related difference in spatial ability found in adolescents persists into adulthood. Regression analyses demonstrated a significant relation between puberty ratings and performance on the mental rotation test, with later maturers scoring higher than earlier maturers. There were no maturation-related differences on the other tests. Significant sex differences were found on all tests. Consistent with previously reported cognitive differences between males and females, females scored higher on the verbal test, and males scored higher on the 2 spatial tests. (15 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Aiming error under transformed spatial mappings suggests a structure for visual-motor maps.

Transformed spatial mappings were used to perturb normal visual–motor processes and reveal the structure of internal spatial representations used by the motor control system. In a 2-D discrete aiming task performed under rotated visual–motor mappings, the pattern of spatial movement error was the same for all Ss: peak error between 90° and 135° of rotation and low error for 180° rotation. A two-component spatial representation, based on oriented bidirectional movement axes plus direction of travel along such axes, is hypothesized. Observed reversals of movement direction under rotations greater than 90° are consistent with the hypothesized structure. Aiming error under reflections, unlike rotations, depended on direction of movement relative to the axis of reflection (H. A. Cunningham and M. Pavel, in press). RT and movement time effects were observed, but a speed-accuracy tradeoff was found only for rotations for which the direction-reversal strategy could be used. Finally, adaptation to rotation operates at all target locations equally but does not alter the relative difficulty of different rotations. Structural properties of the representation are invariant under learning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Age-related reduction in 3-D visual motion priming.

In 3 experiments, younger and older adults judged the perceived motion of three-dimensional (3-D) figures that rotated in depth either unambiguously or ambiguously. Both groups were found to be equivalent in judging the direction of single rotations of the simulated 3-D objects (Experiment 1). In Experiments 2 and 3, a single unambiguous rotation (prime) was followed 0-3200 ms later by an ambiguous rotation (target). Motion priming was indicated by the disambiguation of the second rotation by the first rotation. 3-D motion priming was initially found to be similar in young and old, but it rapidly reduced in the older participants compared to the younger ones. Using a nonluminance depth cue—occlusion—to induce 3-D motion, diminished contrast sensitivity in the elderly was ruled out as a cause of the reduced priming. The results show that 3-D motion priming exhibits robust age-related decline. An age-related decrease in temporal persistence may account for the reduction in 3-D motion priming in older adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Determinants of the perception of rotational motion: Orientation of the motion to the object and to the environment.

The results of two experiments suggest that strong constraints on the ability to imagine rotations extend to the perception of rotations. Participants viewed stereographic perspective views of rotating squares, regular polyhedra, and a variety of polyhedral generalized cones, and attempted to indicate the orientation of the axis and planes of rotation in terms of one of the 13 canonical directions in 3D space. When the axis and planes of a rotation were aligned with principal directions of the environment, participants could indicate the orientation of the motion well. When a rotation was oblique to the environment, the orientation of the object to the motion made a very large difference to performance. Participants were fast and accurate when the object was a generalized cone about the axis of rotation or was elongated along the axis. Variation of the amount of rotation and reflection symmetry of the object about the axis of rotation was not powerful. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The role of dynamic information in the recognition of unfamiliar faces

The effects of movement on unfamiliar face recognition were investigated. In an incidental learning task, faces were studied either as computer-animated (moving) displays or as a series of static images, with identical numbers of frames shown for each. The movements were either nonrigid transformations (changes in expression) or rigid rotations in depth (nodding or shaking). At test, participants saw either single, static images or moving sequences. Only one experiment showed a significant effect of study type, in favor of static instances. There was no additional advantage from studying faces in motion in these experiments, in which both study types showed the same amounts of information. Recognition memory was relatively unaffected by changes in expression between study and test. Effects of viewpoint change were large when expressive transformations had been studied but much smaller when rigid rotations in depth had been studied. The series of experiments did reveal a slight advantage for testing memory with moving compared with static faces, consistent with recent findings using familiar faces. Future work will need to examine whether such effects may also be due to the additional information provided by an animated sequence.     

Mental rotation: Cross-task training and generalization.

It is well established that performance on standard mental rotation tasks improves with training (Peters et al., 1995), but thus far there is little consensus regarding the degree of transfer to other tasks which also involve mental rotation. In Experiment 1, we assessed the effect of mental rotation training on participants' Mental Rotation Test (MRT) scores. Twenty-eight participants were randomly assigned to one of three groups: a “One-Day Training,” “Spaced Training,” or “No Training” group. Participants who received training achieved higher scores on the MRT, an advantage that was still evident after 1 week. Distribution of training did not affect performance. Experiment 2 assessed generalization of mental rotation training to a more complex mental rotation task, laparoscopic surgery. Laparoscopic surgical skills were assessed using Fundamentals of Laparoscopic Surgery (FLS) tasks. Thirty-four participants were randomly assigned to a “Full Mental Rotation Training, MRT and FLS,” “MRT and FLS,” or “FLS-only” group. MRT results from Experiment 1 were replicated and mental rotation training was found to elicit higher scores on the MRT. Further, mental rotation training was found to generalize to certain laparoscopic surgical tasks. Participants who obtained mental rotation training performed significantly better on mental-rotation dependent surgical tasks than participants who did not receive training. Therefore, surgical training programs can use simple computer or paper-based mental rotation training instead of more expensive materials to enhance certain aspects of surgical performance of trainees. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Development of three-dimensional form perception.

In 3 experiments with infants and one with adults we explored the generality, limitations, and informational bases of early form perception. In the infant studies we used a habituation-of-looking-time procedure and the method of Kellman (1984), in which responses to 3-dimensional (3-D) form were isolated by habituating 16-wk-old Ss to a single object in 2 different axes of rotation in depth, and testing afterward for dishabituation to the same object and to a different object in a novel axis of rotation. In Exp I, continuous optical transformations given by moving 16-wk-old observers around a stationary 3-D object specified 3-D form to infants. In Exp II, we found no evidence of 3-D form perception from multiple, stationary, binocular views of objects by 16- and 24-wk-olds. Exp IIIA indicated that perspective transformations of the bounding contours of an object, apart from surface information, can specify form at 16 wks. Exp IIIB provided a methodological check, showing that adult Ss could neither perceive 3-D forms from the static views of the objects in Exp IIIA nor match views of either object across different rotations by proximal stimulus similarities. The results identify continuous perspective transformations, given by object or observer movement, as the informational bases of early 3-D form perception. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Slow and steady often ties the race: Effects of item-specific and relational processing on cumulative recall.

Analysis of cumulative recall curves originally led to the conclusion that asymptotic recall is inversely related to the rate of approaching asymptote. This finding suggests that recall differences between conditions on a short test would continue to exist with longer tests. However, this assumption is not always correct. In Experiments 1 and 2, orienting tasks promoting relational processing produced an initial recall advantage over item-specific processing tasks, but the advantage diminished by the end of the recall period. In Experiment 3, item-specific tasks produced a recall advantage over the relational processing task, but this advantage was manifested only after several minutes of recall. Experiments 4 and 5 extended these results. It was suggested that the results of a single recall test can be misleading when conditions differ in the amount of relational and/or item-specific information encoded. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Mate choice and mate competition influence male body size in Japanese medaka

A sexual size dimorphism usually occurs when size-dependent reproductive advantages exist in only one sex. Studies on Japanese medaka, Oryzias latipes, have demonstrated reproductive size advantages in females but not in males, even though males and females are similar in body size. We conducted mate-choice and mate-copying tests in which a female could first associate with, then mate with, either a large (>/=1 sd+X standard length) or a small male (相似文献   

Perceived orientation of axis rotation in structure-from-motion.

Perceived orientation of axis of rotation and accuracy in discriminating fixed-axis from nonfixed-axis rotations were investigated for orthographic projections of three-dimensional rotating objects. The principal findings were (1) the slant of the axis of rotation was systematically misperceived; (2) in both two-view and multiview displays, the perceived slant of the axis of rotation was well-predicted by the ratio between the deformation (a property of the first-order optic flow) and the component parallel to the image plane of the global velocity vector; (3) if this ratio was kept constant in each frame transition of the stimulus sequence (or it was varied), then the stimuli tended to be judged as fixed-axis rotations (or as nonfixed-axis rotations), regardless of whether they simulated a fixed-axis rotation or not; and (4) the tilt of the axis of rotation was perceived in two-view displays with a very small error. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Quantitative characterization of three-dimensional damage evolution in a wrought Al-alloy under tension and compression

Three-dimensional (3-D) microstructural damage due to cracking of Fe-rich intermetallic particles is quantitatively characterized as a function of strain under compression and tension in an Al-Mg-Si base wrought alloy. The 3-D number fraction of damaged (cracked) particles, their average volume, average surface area, and shape factor are estimated at different strain levels for deformation under uniaxial tension and compression. It is shown that, depending on the type of loading, loading direction, particle shape, and microstructural anisotropy, the two-dimensional (2-D) number fraction of the damaged particles can be smaller or larger than the corresponding true 3-D number fraction. Under uniaxial tension, the average volume and surface area of cracked particles decrease with the strain. However, the average volume and surface area of the cracked particles increase with the increase in the compressive strain, implying that more and more larger elongated particles crack at higher and higher stress levels, which is contrary to the predictions of the existing particle cracking theories. In this alloy, the damage development due to particle cracking is intimately coupled with the particle rotations. The differences in the damage evolution under tension and compression are explained on the basis of the differences in the particle rotation tendencies under these two loading conditions.     

Mental rotation interferes with response preparation.

Reaction times (RTs) and lateralized readiness potentials (LRPs) were studied to find out whether response preparation begins after mental rotation finishes, as assumed by discrete-stage models. Stimuli were disoriented normal or mirror-image characters, with character name determining which hand would respond. In Experiment 1, the normal/mirror-image information determined whether the response was to be executed (go) or withheld (no-go), and LRPs indicated that responses were weakly prepared before the end of mental rotation. Mental rotation was not required in Experiment 2, and significantly more response preparation was observed. In Experiment 3, probe RT trials embedded in the mental rotation task indicated that hand information is available to the response preparation process during rotation. Apparently, some response preparation occurs before mental rotation finishes, but rotation interferes with response preparation. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Visuomotor rotations of varying size and direction compete for a single internal model in a motor working memory.

When participants adapt to equal and opposite visuomotor rotations in close temporal proximity, memory of the 1st is not consolidated. The authors investigated whether this retrograde interference depends on the use of equal and opposite rotations. On Day 1, different groups of participants adapted to a -30° rotation followed 5 min later by rotations of +30°, +60°, or -60°. On Day 2, all groups were retested on the -30° rotation. Either retrograde interference (in groups who adapted to rotations of opposite sign on Day 1) or retrograde facilitation (in the remaining group) was observed. In all groups, learning of the 2nd rotation resulted in unlearning of the first, indicating that all visuomotor rotations compete for common working memory resources. (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)     

Updating displays after imagined object and viewer rotations.

Six experiments compared spatial updating of an array after imagined rotations of the array versus viewer. Participants responded faster and made fewer errors in viewer tasks than in array tasks while positioned outside (Experiment 1) or inside (Experiment 2) the array. An apparent array advantage for updating objects rather than locations was attributable to participants imagining translations of single objects rather than rotations of the array (Experiment 3). Superior viewer performance persisted when the array was reduced to 1 object (Experiment 4); however, an object with a familiar configuration improved object performance somewhat (Experiment 5). Object performance reached near-viewer levels when rotations included haptic information for the turning object. The researchers discuss these findings in terms of the relative differences in which the human cognitive system transforms the spatial reference frames corresponding to each imagined rotation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Mental rotation of facial profiles: Age-, sex-, and ability-related differences.

48 adults (mean age 28 yrs 4 mo), 48 8th graders, and 48 4th graders determined what the left–right orientations of rotated facial profiles would be were the profiles upright. There were 24 males and 24 females in each group. Ss were all administered the Raven Standard Progressive Matrices and the Picture Vocabulary and Spatial Ability subtests of the Woodcock-Johnson Psycho-Educational Battery. Results indicate that rate of mental rotation and combined rate of encoding, comparison, and response increased with age. Findings are consistent with a speed–accuracy tradeoff explanation of previous discrepancies in developmental studies of mental rotation. Female Ss' rates of mental rotation were slower on average and more variable than male Ss. Within the entire sample, there was a modest correlation between the ability test scores and both latency and error parameters derived from the rotation task. Only error rate was discriminantly related to spatial ability, however. Patterns of correlations between processing parameters and test scores differed between age groups and, within age groups, between sexes. Mental rotation showed a significant relation to spatial ability only in 4th graders. (32 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)