Dichotic listening and left-right confusion

The present study examined the relationship between individual differences in dichotic listening (DL) and the susceptibility to left-right confusion (LRC). Thirty-six men and 59 women completed a consonant-vowel DL test, a behavioral LRC task, and an LRC self-rating questionnaire. Significant negative correlations between overall DL accuracy and LRC rates in men (behavioral task) and self-ratings in women, indicated that the more participants struggled with left-right discrimination, the fewer DL syllables they reported correctly. However, there was no relationship between LRC and the typical right ear advantage. Thus, there is a sex- and task-dependent relationship between LRC and overall DL accuracy, but not between LRC and ear asymmetry. It is concluded that (a) atypical ear asymmetries, as in certain clinical populations, cannot be explained by associated deficits in left-right discrimination, and (b) LRC can negatively affect task performance, even when participants do not have to make explicit "left" versus "right" decisions.     

Item type,occlusion, and gender differences in mental rotation

Two experiments were conducted to examine the role of item type in mental rotation. In each experiment, participants completed two computerized mental rotation tasks, one with blocks as stimuli and one with human figures as stimuli. The tasks were formatted either as a multiple-choice psychometric test (Experiment 1) or as a same–different type task (Experiment 2). Aside from the expected replication of a decreased effect of occlusion on women's accuracy when processing human figures compared to block figures, it was hypothesized that response times would increase when processing the complex but familiar human figures, compared to the simple but unfamiliar block figures. In Experiment 1, the results relevant to occlusion were replicated. However, the presence of a speed–accuracy trade-off suggested that participants processed human figures faster but less accurately than block figures. In Experiment 2, both men and women performed faster and more accurately when processing occluded human figures than when processing nonoccluded human figures. The effect of item type, its potential link to embodied cognition, and the role of strategy selection on gender differences in mental rotation are discussed.     

Sex differences in parietal lobe morphology: relationship to mental rotation performance

Structural magnetic resonance imaging (MRI) studies of the human brain have reported evidence for sexual dimorphism. In addition to sex differences in overall cerebral volume, differences in the proportion of gray matter (GM) to white matter (WM) volume have been observed, particularly in the parietal lobe. To our knowledge there have been no studies examining the relationship between the sex differences in parietal lobe structure and function. The parietal lobe is thought to be involved in spatial ability, and particularly involved in mental rotation. The purpose of this study is to examine whether sex differences in parietal lobe structure are present, and if present to relate these differences to performance on the mental rotations test (MRT). We found that women had proportionately greater gray matter volume in the parietal lobe compared to men, and this morphologic difference was disadvantageous for women in terms of performance on the MRT. In contrast, we found that men compared to women had proportionately greater parietal lobe surface area, and this morphologic difference was associated with a performance advantage for men on mental rotation. These findings support the possibility that the sexual dimorphism in the structure of the parietal lobe is a neurobiological substrate for the sex difference in performance on the mental rotations test.     

An investigation of mental rotation in infancy using change detection

Two experiments were conducted to examine mental rotation in 6- to 12-month-old infants (N = 166) using a change detection task. These experiments were replications of Lauer and Lourenco (Lauer et al., 2015; Lauer & Lourenco, 2016), using identical stimuli and variations of their procedure, including an exact replication conducted in a laboratory setting (Experiment 1), and an online assessment using Lookit (Scott et al.,2017; Scott & Schulz, 2017) (Experiment 2). Both experiments failed to replicate the results of the original study; in neither experiment did infants’ behavior provide evidence that they mentally rotated the object. Results are discussed in terms of the robustness of mental rotation in infancy and about limits in our experimental procedures for uncovering perceptual and cognitive abilities in infants.     

Suitable stimuli to obtain (no) gender differences in the speed of cognitive processes involved in mental rotation

Gender differences in speed of perceptual comparison, of picture-plane mental rotation, and in switching costs between trials that do and do not require mental rotation, were investigated as a function of stimulus material with a total sample size of N=360. Alphanumeric characters, PMA symbols, animal drawings, polygons and 3D cube figures were used with an otherwise completely equivalent experimental design in which age and speed-based IQ were comparable across male and female groups. Small gender-related differences in speed of perceptual comparison were found with the magnitude as well as the direction depending upon the stimulus material. Polygons were the only material that produced substantial and reliable gender differences in mental rotation speed, and additionally revealed gender differences in switching costs. Thus, whereas gender differences in paper-pencil mental rotation tests constitute an empirical reality, the generalization that men outperform women in the speed of mental rotation was not supported in the present experiment.     

A lateralization of function approach to sex differences in spatial ability: a reexamination

The current study assessed the lateralization of function hypothesis (Rilea, S. L., Roskos-Ewoldsen, B., & Boles, D. (2004). Sex differences in spatial ability: A lateralization of function approach. Brain and Cognition, 56, 332–343) which suggested that it was the interaction of brain organization and the type of spatial task that led to sex differences in spatial ability. A second purpose was to evaluate explanations for their unexpected findings on the mental rotation task. In Experiment 1, participants completed the Water Level, Paper Folding, and mental rotation tasks (using an object-based or self-based perspective), presented bilaterally. Sex differences were only observed on the Water Level Task; a right hemisphere advantage was observed on Water Level and mental rotation tasks. In Experiment 2, a human stick figure or a polygon was mentally rotated. Men outperformed women when rotating polygons, but not when rotating stick figures. Men demonstrated a right hemisphere advantage when rotating polygons; women showed no hemisphere differences for either stimulus. Thus, hemisphere processing, task complexity, and stimulus type may influence performance for men and women across different spatial measures.     

Gender differences in unilateral spatial neglect within 24 hours of ischemic stroke

Hemispatial neglect is a common and disabling consequence of stroke. Previous reports examining the relationship between gender and the incidence of unilateral spatial neglect (USN) have included either a large numbers of patients with few neglect tests or small numbers of patients with multiple tests. To determine if USN was more common and/or severe in men or women, we examined a large group of patients (312 right-handed) within 24 hours of acute right hemisphere ischemic stroke. Multiple spatial neglect tasks were used to increase the sensitivity of neglect detection. No differences based upon gender were observed for the prevalence, severity, or a combined task measure of USN.     

Bodies and occlusion: Item types,cognitive processes,and gender differences in mental rotation

The aim of the current study was to reexamine previous findings in which the magnitude of the male advantage in mental rotation abilities increased when participants mentally rotated occluded versus nonoccluded items and decreased when participants mentally rotated human figures versus blocks. Mainly, the study aimed to address methodological issues noted on previous human figure mental rotations tests as the items composed of blocks and human body were probably not equivalent in terms of their cognitive requirements. Our results did not support previous research on embodied cognition as mental rotation performance decreased among both men and women when mentally rotating human figures compared to block items. However, for women, the effect of occlusion was decreased when mentally rotating human figures. Results are discussed in terms of task difficulty and gender differences in confidence and guessing behaviour.     

Evaluating the contribution of different item features to the effect size of the gender difference in three-dimensional mental rotation using automatic item generation

In complex three-dimensional mental rotation tasks males have been reported to score up to one standard deviation higher than females. However, this effect size estimate could be compromised by the presence of gender bias at the item level, which calls the validity of purely quantitative performance comparisons into question. We hypothesized that the effect of gender bias at the level of distinct item design features could lead to either an over- or underestimation of reported effect sizes of the gender difference in three-dimensional mental rotation. Using automatic item generation we conducted a series of psychometric experiments in which we independently manipulated one out of four different item design features that have exhibited a gender bias in the previous studies (study 1). This was done in a between-subjects design. The results indicated that gender bias caused by item design features linked to the perceptual stadium of mental rotation led to an overestimation of the effect size of the gender difference while item design features associated with the encoding and transformational stadium resulted in an underestimation of the effect size of the gender difference. In study 2 we tested the hypothesis that the gender difference still remains while controlling for the item design features causing gender bias. The results suggest that a significant portion of the gender difference may be attributable to perceptual and encoding processes involved in mental rotation.     

Sex differences in spatial ability: a lateralization of function approach

The current study was designed to examine whether the extent of the male advantage in performance on a spatial task was determined by the extent to which the task was right-hemisphere dependent. Participants included 108 right-handed men and women who completed the mental rotation, waterlevel, and paperfolding tasks, all of which were presented bilaterally. The results partially supported the hypothesis. On the mental rotation task, men showed a right-hemisphere advantage, whereas women showed no hemispheric differences; however, no overall sex differences were observed. On the waterlevel task, men outperformed women, and both men and women showed a right-hemisphere advantage. On the paperfolding task, no sex or hemispheric differences were observed. Although the findings of the current study were mixed, the study provides a framework for examining sex differences across different types of spatial ability.     

At the interface of social cognition and psychometrics: Manipulating the sex of the reference class modulates sex differences in personality traits

Psychometric surveys suggest that sex differences in personality are minimal. Herein, we argue that (a) the mind is likely biased toward assessing oneself relative to same-sex others, and (b) this bias may affect the measurement of sex differences in personality. In support of this, an experiment demonstrates modulation of sex differences on the HEXACO facets by manipulating the sex of the “reference class”—the group of people subjects compare themselves to when making self-assessments on survey items. Although patterns varied across traits, sex differences were relatively small in the “unspecified” and “same-sex” reference class conditions—but substantially larger in the “opposite-sex” condition. These findings point to a same-sex comparison bias that may impact the measurement of sex differences in personality.     

Sex differences in mental rotation with polygons of different complexity: Do men utilize holistic processes whereas women prefer piecemeal ones?

Sex differences in mental rotation were investigated as a function of stimulus complexity with a sample size of N = 72. Replicating earlier findings with polygons, mental rotation was faster for males than for females, and reaction time increased with more complex polygons. Additionally, sex differences increased for complex polygons. Most importantly, however, mental rotation speed decreased with increasing complexity for women but did not change for men. Thus, the sex effects reflect a difference in strategy, with women mentally rotating the polygons in an analytic, piecemeal fashion and men using a holistic mode of mental rotation.     

Development of mental rotation in 3- to 5-year-old children

We assessed 3- to 5-year-olds’ mental rotation abilities using a new puzzle paradigm. It allows for assessment of mental rotation abilities in children younger than 5 years, using a task comparable to ones used with older children and adults. Children saw pairs of asymmetrical ghost figures, either as three-dimensional cut-outs or two-dimensional paper versions, in seven orientations. One of the ghosts fit into a hole if rotated right-side up – the other ghost was its mirror image and would not fit. Children were asked to turn the ghosts in their heads and choose the one that would fit into the hole. The number of children who chose the correct ghost above chance in the three-dimensional version of the task increased dramatically from 10% of 3-year-olds to 95% of 5-year-olds; average accuracy also increased significantly, from 54% to 83%. The two-dimensional paper version yielded similar results. These results indicate considerable development in mental rotation between 3 and 5 years.     

Considering sex differences in anxiety and its disorders across the life span: A construct-validation approach

One neglected avenue to understanding anxiety disorders is through studying patterns of sex differences, which may suggest the need for modification in definitions of anxiety and its disorders, their operationalization and measurement, and the theories associated with these constructs. This article begins with a comprehensive review of sex diffrences across the life span that supports the widely held view that most anxiety disorders are more common among females than males. Subsequently, we offer an analysis of the possible sources of sex differences from a construct-validity perspective, with emphasis on understanding whether sex differences have their basis in methodological problems, measurement or definitional problems, or problems in extant theories of anxiety themselves.     

Mental rotation and handedness: differences in object-based and egocentric transformations

This study investigates mental rotation performance of right- and left-handers in object-based and egocentric mental rotation tasks using human body stimuli with an outstretched arm in front and back view. Previous literature suggests that right-handers show a slightly better mental rotation performance than left-handers. 42 participants, 14 left-handers and 28 right-handers, completed a mental rotation task with object-based and egocentric transformation of a human figure which was displayed either in front or back view. The main result was a three-way interaction between the factors “kind of transformation”, “handedness” and “view” in a way, that right-handers show significantly faster reaction times then left-handers in front view object-based transformations because of the additional in-depth rotation for front view stimuli. This difference disappeared in egocentric tasks due to the modification of onés own perspective to solve the task. The results of this study show that right-handers not generally outperform left-handers in mental rotation tasks but only if more cognitive resources are needed.     

Mental rotation performance and the effect of gender in fourth graders and adults

The DSM-IV implicitly assumes that development is uniform across ability domains, which implies that relationships between ability measures do not differ across development. We assessed whether correlations between measures of nine ability constructs differed across samples of children aged 3 – 5 (n = 117), 6 – 8 (n = 116), 9 – 11 (n = 124) and 12 – 14 years (n = 92). LISREL analyses show that correlations in each age group differ from those of each other age group. Parallel analyses indicate that the latent structure of ability differs across age groups. We conclude that shared maturational processes, including changes in the connectivity of neural systems, are responsible for decreasingly and increasingly strong relationships between some ability measures.     

Manual rotation training improves direction-estimations in a virtual environmental space

This study investigated in a virtual environment, whether the training of a small-scale ability, i.e., manual or mental rotation, has an influence on the large-scale ability to estimate a direction. Ninety-six participants completed a direction estimation task as a pretest and then received either a manual rotation or a mental rotation training or played a nonspatial computer game. After that they completed the direction estimation task once again. The results showed that the direction estimation error decreased from the pre- to posttest only for the manual rotation training group. For that, the small-scale spatial ability was at least partially related to the large-scale ability, which supports the Partial Dissociation Model.     

Sex differences in a human analogue of the Radial Arm Maze: the "17-Box Maze Test"

This study investigated sex differences in spatial memory using a human analogue of the Radial Arm Maze: a revision on the Nine Box Maze originally developed by called the 17-Box Maze Test herein. The task encourages allocentric spatial processing, dissociates object from spatial memory, and incorporates a within-participants design to provide measures of location and object, working and reference memory. Healthy adult males and females (26 per group) were administered the 17-Box Maze Test, as well as mental rotation and a verbal IQ test. Females made significantly fewer errors on this task than males. However, post hoc analysis revealed that the significant sex difference was specific to object, rather than location, memory measures. These were medium to large effect sizes. The findings raise the issue of task- and component-specific sexual dimorphism in cognitive mapping.     

Visual image retention does not contribute to modulation of event-related potentials by mental rotation

Rotation of a visual image in mind is associated with a slow posterior negative deflection of the event-related potential (ERP), termed rotation-related negativity (RRN). Retention of a visual image in short-term memory is also associated with a slow posterior negative ERP, termed negative slow wave (NSW). We tested whether short-term memory retention, indexed by the NSW, contributes to the RRN. ERPs were recorded in the same subjects in two tasks, a mental rotation task, eliciting the RRN, and a visual short-term memory task, eliciting the NSW. Over both right and left parietal scalp, no association was found between the NSW and the RRN amplitudes. Furthermore, adjusting for the effect of the NSW had no influence on a significant association between the RRN amplitude and response time, an index of mental rotation performance. Our data indicate that the RRN reflects manipulation of a visual image but not its retention in short-term memory.     

No sex differences in spatial location memory for abstract designs

Previous research has demonstrated a female advantage, albeit imperfectly, on tests of object location memory where object identity information is readily available. However, spatial and visual elements are often confounded in the experimental tasks used. Here spatial and visual memory performance was compared in 30 men and 30 women by presenting 12 abstract designs in a spatial array for recall and recognition (visual memory) and spatial location ("object" location memory). Object location memory was measured via a sensitive absolute displacement score defined as the distance in mms between the position assigned to the object during recall and the actual position it originally occupied. There were no sex differences in either the visual or spatial location tests. Controlling for age and estimated IQ scores made no impact on the results. These data suggest an absence of a sex difference in purely visual and spatial aspects of object location memory.