An early sex difference in the relation between mental rotation and object preference

A meta-analysis of mental rotation in the first years of life

Mental rotation, the cognitive process of moving an object in mind to predict how it looks in a new orientation, is coupled to intelligence, learning, and educational achievement. On average, adolescent and adult males solve mental rotation tasks slightly better (i.e., faster and/or more accurate) than females. When such behavioral differences emerge during development, however, remains poorly understood. Here we analyzed effect sizes derived from 62 experiments conducted in 1705 infants aged 3-16 months. We found that male infants recognized rotated objects slightly more reliably than female infants. This difference survives correction for small degrees of publication bias. These findings indicate that gender differences in mental rotation are small and not robustly detectable in the first months of postnatal life. RESEARCH HIGHLIGHTS: We analyzed effect sizes of 62 mental rotation experiments including 1705 infants. Looking time reveals that 3-16-months-old infants are able to perform mental rotation. Mental rotation is slightly more reliable in male infants compared to female infants. Gender difference in mental rotation is robust to small degrees of publication bias.

Malleability of spatial skills: bridging developmental psychology and toy design for joyful STEAM development

Previous research has established that advances in spatial cognition predict STEAM success, and construction toys provide ample opportunities to foster spatial cognition. Despite various construction toy designs in the market, mostly brick-shaped building blocks are used in spatial cognition research. This group of toys is known to enhance mental rotation; however, mental rotation is not the only way to comprehend the environment three-dimensionally. More specifically, mental folding and perspective taking training have not received enough attention as they can also be enhanced with the construction toys, which are framed based on the 2×2 classification of spatial skills (intrinsic-static, intrinsic-dynamic, extrinsic-static, extrinsic-dynamic). To address these gaps, we compile evidence from both developmental psychology and toy design fields to show the central role played by mental folding and perspective taking skills as well as the importance of the variety in toy designs. The review was conducted systematically by searching peer reviewed design and psychology journals and conference proceedings. We suggest that, over and above their physical properties, construction toys offer affordances to elicit spatial language, gesture, and narrative among child-caregiver dyads. These interactions are essential for the development of spatial skills in both children and their caregivers. As developmental psychology and toy design fields are two domains that can contribute to the purpose of developing construction toys to boost spatial skills, we put forward six recommendations to bridge the current gaps between these fields. Consequently, new toy designs and empirical evidence regarding malleability of different spatial skills can contribute to the informal STEAM development.

A Novel Approach to Assessing Infant and Child Mental Rotation

Mental rotation is a critically important, early developing spatial skill that is related to other spatial cognitive abilities. Understanding the early development of this skill, however, requires a developmentally appropriate assessment that can be used with infants, toddlers, and young children. We present here a new eye-tracking task that uses a staircase procedure to assess mental rotation in 12-, 24-, and 36-month-old children (N = 41). To ensure that all children understood the task, the session began with training and practice, in which the children learned to fixate which of two houses a giraffe, facing either left or right, would approach. The adaptive two-up, one-down staircase procedure assessed the children's ability to fixate the correct house when the giraffe was rotated in 30° (up) or 15° (down) increments. The procedure was successful, with most children showing evidence of mental rotation. In addition, the children were less likely to succeed as the angle of rotation increased, and the older children succeeded at higher angles of rotation than the younger children, replicating previous findings with other procedures. The present study contributes a new paradigm that can assess the development of mental rotation in young children and holds promise for yielding insights into individual differences in mental rotation.

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.

Sex differences matter: Males and females are equal but not the same

Sex differences between males and females can be detected early in life. They are present also later even to a much greater extent affecting our life in adulthood and a wide spectrum of physical, psychological, cognitive, and behavioral characteristics. Moreover, sex differences matter also in individual's health and disease. In this article, we reviewed at first the sex differences in brain organization and function with respect to the underlying biological mechanisms. Since the individual functional differences in the brain, in turn, shape the behavior, sex-specific psychological/behavioral differences that can be observed in infants but also adults are consequently addressed. Finally, we briefly mention sex-dependent variations in susceptibility to selected disorders as well as their pathophysiology, diagnosis, and response to therapy. The understanding of biologically determined variability between males and females can have important implications, especially in gender-specific health care. We have the impression that it is very important to emphasize that sex matters. Males and females are differently programmed by nature, and it must be respected. Even though we as males and females are not the same, we would like to emphasize that we are still equal and together form a worthy colorful continuum.

Locomotion training contributes to 6-month-old infants' mental rotation ability

This study investigated whether a locomotion training contributes to mental rotation performance in infants. Thirty 6-month-old pre-locomotor infants were randomly assigned to either a locomotion training or a control group which received no training. The general status of motor and cognitive development measured with the Bayley Scales did not differ between the 2 groups. Mental rotation was compared before and after the trainings using a mental rotation task in which infants were habituated to a rotating object and then tested with the same habituation object presented in a previously unseen angle and the corresponding mirror object. Results revealed that only infants in the locomotion training group showed a significant change in their looking durations at the test objects (habituation vs. mirror) in the mental rotation task. This suggests that self-produced locomotion experience can affect infants' mental rotation.

Visual foundations of Euclidean geometry

Geometry defines entities that can be physically realized in space, and our knowledge of abstract geometry may therefore stem from our representations of the physical world. Here, we focus on Euclidean geometry, the geometry historically regarded as "natural". We examine whether humans possess representations describing visual forms in the same way as Euclidean geometry - i.e., in terms of their shape and size. One hundred and twelve participants from the U.S. (age 3-34 years), and 25 participants from the Amazon (age 5-67 years) were asked to locate geometric deviants in panels of 6 forms of variable orientation. Participants of all ages and from both cultures detected deviant forms defined in terms of shape or size, while only U.S. adults drew distinctions between mirror images (i.e. forms differing in "sense"). Moreover, irrelevant variations of sense did not disrupt the detection of a shape or size deviant, while irrelevant variations of shape or size did. At all ages and in both cultures, participants thus retained the same properties as Euclidean geometry in their analysis of visual forms, even in the absence of formal instruction in geometry. These findings show that representations of planar visual forms provide core intuitions on which humans' knowledge in Euclidean geometry could possibly be grounded.

Bringing Home Baby Euclid: Testing Infants' Basic Shape Discrimination Online

Online developmental psychology studies are still in their infancy, but their role is newly urgent in the light of the COVID-19 pandemic and the suspension of in-person research. Are online studies with infants a suitable stand-in for laboratory-based studies? Across two unmonitored online experiments using a change-detection looking-time paradigm with 96 7-month-old infants, we found that infants did not exhibit measurable sensitivities to the basic shape information that distinguishes between 2D geometric forms, as had been observed in previous laboratory experiments. Moreover, while infants were distracted in our online experiments, such distraction was nevertheless not a reliable predictor of their ability to discriminate shape information. Our findings suggest that the change-detection paradigm may not elicit infants' shape discrimination abilities when stimuli are presented on small, personal computer screens because infants may not perceive two discrete events with only one event displaying uniquely changing information that draws their attention. Some developmental paradigms used with infants, even those that seem well-suited to the constraints and goals of online data collection, may thus not yield results consistent with the laboratory results that rely on highly controlled settings and specialized equipment, such as large screens. As developmental researchers continue to adapt laboratory-based methods to online contexts, testing those methods online is a necessary first step in creating robust tools and expanding the space of inquiry for developmental science conducted online.

Mental rotation task performance in relation to sexual and gender diversity in Thailand

Neurohormonal theory argues that organizational effects of hormone exposure influence sexual orientation and gender identity, as well as sex differences in visuospatial cognition. This study examined mental rotation task (MRT) performance in a diverse Thai sample (N = 980). Thai culture has several third genders: individuals assigned male at birth (AMAB) who are feminine and attracted to cis men (i.e., sao praphet song); individuals assigned female at birth (AFAB) who are masculine and attracted to feminine individuals (i.e., toms); AFAB individuals who are feminine and attracted to toms (i.e., dees); and sexual orientation categories similar to Western culture (e.g., gay, lesbian, bi). On the MRT, straight cis men outperformed straight cis women. Results were consistent with organizational effects among AMAB individuals, with straight cis men outperforming gay cis men and sao praphet song. Among AFAB individuals, however, only bi and lesbian cis women outperformed dees. Overall, support for neurohormonal theory was limited among AFAB individuals, but MRT performance among AMAB individuals was consistent with organizational effects. This study informs our understanding of visuospatial sex/gender differences and the applicability of neurohormonal theory across cultures.

How 9-month-old crawling infants profit from visual-manual rotations in a mental rotation task

Studies show that visual-manual object exploration influences spatial cognition, and specifically mental rotation performance in infancy. The current work with 9-month-old infants investigated which specific exploration procedures (related to crawling experience) support mental rotation performance. In two studies, we examined the effects of two different exploration procedures, manual rotation (Study 1) and haptic scanning (Study 2), on subsequent mental rotation performance. To this end, we constrained infants' exploration possibilities to only one of the respective procedures, and then tested mental rotation performance using a live experimental set-up based on the task used by Moore and Johnson (2008). Results show that, after manual rotation experience with a target object, crawling infants were able to distinguish between exploration objects and their mirror objects, while non-crawling infants were not (Study 1). Infants who were given prior experience with objects through haptic scans (Study 2) did not discriminate between objects, regardless of their crawling experience. Results indicated that a combination of manual rotations and crawling experience are valuable for building up the internal spatial representation of an object.

Male sexual orientation, gender nonconformity, and neural activity during mental rotations: an fMRI study

The cross-sex shift hypothesis predicts that gay men should perform more like heterosexual women on important neurocognitive tasks on which men score higher than women, such as mental rotation. Studies also suggest sex differences exist in the neural correlates of mental rotation. However, no studies have taken sexual orientation into account or considered within-group variation attributable to recalled gender nonconformity (a developmental trait reliably associated with human nonheterosexuality). We quantified the neural correlates of mental rotation by comparing two groups of gay men, gender conforming (n = 23) and gender nonconforming (n = 23), to gender conforming heterosexual men (n = 22) and women (n = 22). We observed a sex difference between heterosexual men and women in the premotor cortex/supplementary motor cortex and left medial superior frontal gyrus. We also observed a sex difference as well as a cross-sex shift in gay men who recalled being gender nonconforming as children in the right superior frontal gyrus, right angular gyrus, right amygdala/parahippocampal gyrus, and bilaterally in the middle temporal gyrus and precuneus. Thus, cross-sex shifts may be associated with underlying developmental factors which are associated with sexual orientation (such as gender nonconformity). The results also suggest that gay men should not be studied as a homogenous group.

Gender differences in mothers' spatial language use and children's mental rotation abilities in Preschool and Kindergarten

Mental rotation has emerged as an important predictor of success in Science, Technology, Engineering, and Math (STEM). By the age of 4.5 years, boys outperform girls in these abilities. Because parents use less spatial language with girls at this age (Pruden and Levine, 2017), the amount of spatial language that children are exposed to at home is believed to be one potential contributor to this disparity in preschool age children. To date, it is unclear if this gender difference continues when children enter school. To address this question in this study, children not yet in kindergarten (PreK) and kindergarten and first grade children (K+) were recorded playing with their mothers using magnetic tile toys followed by children's completion of a mental rotation task. As expected, mothers used more spatial language with PreK boys than girls; however, this relationship reversed in K+, with mothers using significantly more spatial language with girls than boys. Surprisingly, despite this, boys outperformed girls on the mental rotation task. These findings suggest that although girls' exposure to spatial language is higher after entry into school, this language difference is not reflected in increases in mental rotation abilities. Thus, earlier exposure to spatial language may be vital for the development of mental rotation abilities.

Spatial activity participation in childhood and adolescence: consistency and relations to spatial thinking in adolescence

Background

Prior research has revealed positive effects of spatial activity participation (e.g., playing with blocks, sports) on current and future spatial skills. However, research has not examined the degree to which spatial activity participation remains stable over time, and little is known about how participating in spatial activities at multiple points in development impacts spatial thinking. In this study, adolescents completed measures of spatial thinking and questionnaires assessing their current and previous participation in spatial activities.

Results

Participation in childhood spatial activities predicted adolescent spatial activity participation, and the relation was stronger for females than for males. Adolescents’ current participation in spatial activities predicted spatial thinking skills, whereas participation in childhood spatial activities predicted adolescents’ spatial habits of mind, even when accounting for factors such as gender and academic performance. No cumulative benefit was incurred due to participating in spatial activities in both childhood and adolescence, and a lack of spatial activities in childhood was not made up for by later spatial activity participation.

Conclusions

These findings reveal a consistently positive relationship in spatial activity participation between childhood and adolescence. Results highlight the importance of participating in spatial activities during childhood, and underscore the differential impact that participation in spatial activities during childhood versus adolescence has on different facets of adolescents’ spatial thinking. Implications for the timing of interventions is discussed.

Infants' sensitivity to shape changes in 2D visual forms

Research in developmental cognitive science reveals that human infants perceive shape changes in 2D visual forms that are repeatedly presented over long durations. Nevertheless, infants' sensitivity to shape under the brief conditions of natural viewing has been little studied. Three experiments tested for this sensitivity by presenting 128 seven-month-old infants with shapes for the briefer durations under which they might see them in dynamic scenes. The experiments probed infants' sensitivity to two fundamental geometric properties of scale- and orientation-invariant shape: relative length and angle. Infants detected shape changes in closed figures, which presented changes in both geometric properties. Infants also detected shape changes in open figures differing in angle when figures were presented at limited orientations. In contrast, when open figures were presented at unlimited orientations, infants detected changes in relative length but not in angle. The present research therefore suggests that, as infants look around at the cluttered and changing visual world, relative length is the primary geometric property by which they perceive scale- and orientation-invariant shape.

Waist-to-Hip Ratio Sensitivity in Early Infancy

The waist-to-hip ratio (WHR) is correlated with health and associated with sex, attractiveness, and age judgments by adults. We examined the development of sensitivity to the WHR by testing 3.5-month-old infants' (N = 71) preference between images depicting different WHRs. Female 3.5-month-olds exhibited a preference for the WHR associated with attractiveness and mate value by adults (0.7) over a larger WHR (0.9). This preference was exhibited when infants were tested on upright stimuli but not when they were tested on inverted stimuli, indicating that low-level differences (e.g., curviness) were not driving performance. This sensitivity to WHR may lay the foundation for more explicit preferences and categorical associations later in life. In contrast to females, male infants failed to exhibit a significant preference for the 0.7 WHR in either orientation, replicating previous findings of female infants' superior processing of social stimuli. Implications for theories of the development of body knowledge and sex differences in social information processing are discussed.

Who Benefits from An Intervention Program on Foundational Skills for Handwriting Addressed to Kindergarten Children and First Graders?

This study examined the effectiveness of a 10-wk intervention program based on occupational therapy principles on visual-motor integration skills and fine motor abilities in kindergartners and first graders. We recruited 55 students tested three times with the Visual-Motor Integration Test (VMI) and Movement Assessment Battery for Children-2 (MABC-2): before the intervention (T1), post-intervention (T2) and one month later (T3). Research findings: Significant improvements were found on VMI between T1 and T2, particularly for kindergartners. Neither group of children demonstrated changes on manual dexterity scores. The present study showed that the intervention program led to different changes in the at-risk of motor impairment group than in the not at-risk children. Results indicated that games and stimulation activities helped children below the 16th percentile over time in the manual dexterity domain. A gender effect was observed, with female children increasing their abilities over time more than male peers. Future research should concentrate on stimulating fine motor skills in hand manipulation and test how these abilities influence graphomotor skills and handwriting over time. Finally, more research is needed to determine the impact of activities and games carried out in educational settings.

The development of mental rotation ability across the first year after birth

Mental rotation (MR) is the ability to imagine the appearance of an object from a different perspective. This ability is involved in many human cognitive and behavioral activities. We discuss studies that have examined MR in infants and its development across the first year after birth. Despite some conflicting findings across these studies, several conclusions can be reached. First, MR may be available to human infants as young as 3 months of age. Second, MR processes in infancy may be similar or identical to MR processes later in life. Third, there may be sex differences in MR performance, in general favoring males. Fourth, there appear to be multiple influences on infants' MR performance, including infants' motor activity, stimulus complexity, hormones, and parental attitudes. We conclude by calling for additional research to examine more carefully the causes and consequences of MR abilities early in life.

Spatial Thinking in Infancy: Origins and Development of Mental Rotation Between 3 and 10 Months of Age

Mental rotation (MR) is the ability to transform a mental representation of an object so as to accurately predict how the object would look from a different angle (Sci 171:701–703, 1971), and it is involved in a number of important cognitive and behavioral activities. In this review we discuss recent studies that have examined MR in infants and the development of MR across the first year after birth. These studies have produced many conflicting results, yet several tentative conclusions can be reached. First, MR may be operational in infants as young as 3 months of age. Second, there may be sex differences in MR performance in infancy, in general favoring males, as there are in children and in adults. Third, there appear to be multiple influences on infants’ MR performance, including infants’ motor activity, stimulus or task complexity, hormones, and parental attitudes. We conclude by calling for additional research to examine more carefully the causes and consequences of MR abilities early in life.

Beyond Biological Sex: Interactive Effects of Gender Role and Sex Hormones on Spatial Abilities

Sex differences in spatial abilities are well documented, even though their underlying causes are poorly understood. Some studies assume a biological basis of these differences and study the relationship of sex hormone levels to spatial abilities. Other studies assume social influences and study the relationship of gender role (masculinity/femininity) to spatial abilities. Contemporary theories postulate a psychobiosocial model of sex differences in spatial abilities, in which both biological (e.g., hormonal) and psychosocial (e.g., gender role) variables interactively modulate spatial abilities. However, few studies have addressed both aspects simultaneously. Accordingly, the present study explores potential interactive effects between gender role and sex hormones on spatial performance. 41 men and 41 women completed a mental rotation and a virtual navigation task. Sex hormone levels and gender role were assessed in all participants. Sex differences favoring men were observed in both tasks. We found that neither sex hormones nor gender role alone emerged as mediators of these sex differences. However, several interactive effects between gender role and sex hormones were identified. Combined effects of masculinity and testosterone were observed for those variables that displayed sex differences. Participants with both, high masculinity and high testosterone showed the best performance. However, this association was further modulated by biological sex and progesterone levels. Furthermore, we observed an interactive effect of femininity, estradiol and testosterone on response times in both tasks. Consistent across both tasks and irrespective of biological sex, testosterone related to response times in participants with low estradiol levels, depending on their femininity. In participants with low femininity, testosterone was related to slower reaction times, while in participants with higher femininity, testosterone was related to faster reaction times.

Sex Differences in Gains Among Hispanic Pre-kindergartners' Mental Rotation Skills

The current study explores change in mental rotation skills throughout the pre-kindergarten year in a Hispanic population to better understand the development of early sex differences in mental rotation. Ninety-six Hispanic children (M = 4 years 8 months) completed a mental rotation task at the beginning and end of pre-kindergarten. Results suggest Hispanic boys and girls differed in gains on mental rotation ability, with boys improving significantly more than girls during pre-kindergarten on a mental rotation task. This study highlights the significance of studying mental rotation abilities in a Hispanic population of pre-kindergarten aged children and suggests the importance of examining sex differences in mental rotation over time, rather than at one time-point, to better understand when sex differences in spatial skills develop. We discuss various factors that potentially affect the growth of spatial skills including the role of early education, spatial experiences, and spatial language input.

What makes a landmark effective in adolescent and adult rats? Sex and age differences in a navigation task

In three experiments, rats of different ages were trained in a circular pool to find a hidden platform whose location was defined in terms of a single landmark, a cylinder outside the pool. Following training, two main components of the landmark, its shape and pattern, were tested individually. Experiment 1 was performed by adolescent and adult rats (Exp. 1a, males; Exp. 1b, females). Adult rats always learned faster than the adolescent animals. On test trials, interesting tendencies were found-mainly, one favoring males on the shape test trial, and another favoring females on the pattern test trial. Experiment 2 was conducted only with adolescent rats, and these males and females did not differ when learning the task. However, on test trials the males learned more about the landmark shape component than about the landmark pattern component, while the females learned equally about the two components of the landmark. Finally, Experiment 3 was conducted only with adult rats, and again the males and females did not differ when learning the task. However, on test trials the males learned equally about the two components of the landmark (shape and pattern), but the females learned more about the landmark pattern component than about the landmark shape component. This set of experiments supports the claim that male and female rats can learn rather different things about a landmark that signals the location of the platform, with age being a critical variable.

Object exploration facilitates 4-month-olds' mental rotation performance

How do infants learn to mentally rotate objects, to imagine them rotating through different viewpoints? One possibility is that development of infants' mental rotation (MR) is facilitated by visual and manual experience with complex objects. To evaluate this possibility, eighty 4-month-olds (40 females, 40 males) participated in an object exploration task with Velcro "sticky mittens" that allow infants too young to grasp objects themselves to nonetheless explore those objects manually as well as visually. These eighty infants also participated in a visual habituation task designed to test MR. Half the infants (Mittens First group) explored the object prior to the MR task, and the other half afterwards (Mittens Second group), to examine the role of immediate prior object experience on MR performance. We compared performance of male and female infants, but found little evidence for sex differences. However, we found an important effect of object exploration: The infants in the Mittens First group who exhibited the highest levels of spontaneous object engagement showed the strongest evidence of MR, but there were no consistent correlations between these measures for infants in the Mittens Second group. These findings suggest an important contribution from object experience to development of MR.

Contribution of underlying processes to improved visuospatial working memory associated with physical activity

BACKGROUND

Working memory is critical for various cognitive processes and can be separated into two stages: short-term memory storage and manipulation processing. Although previous studies have demonstrated that increased physical activity (PA) improves working memory and that males outperform females on visuospatial working memory tasks, few studies have determined the contribution of the two underlying stages to the visuospatial working memory improvement associated with PA. Thus, the aims of the present study were to verify the relationship between physical activity and visuospatial working memory, determine whether one or both stages were affected by PA, and investigate any sex differences.

METHODS

A total of 56 undergraduate students were recruited for this study. Their scores on the International Physical Activity Questionnaire (IPAQ) were used to separate them into either a lower PA (n = 26; IPAQ score ≤3,000 metabolic equivalent [MET]-min/week) or higher PA (n = 30; IPAQ score >3,000 MET-min/week) group. Participants were required to complete three tasks: a visuospatial working memory task, a task that examines the short-term memory storage stage, and a mental rotation task that examines the active manipulation stage.

RESULTS

Participants in the higher PA group maintained similar accuracy but displayed significantly faster reaction times (RT) than those in the lower PA group on the visuospatial working memory and manipulation tasks. By contrast, no difference was observed between groups on the short-term memory storage task. In addition, no effects of sex were detected.

DISCUSSION

Our results confirm that PA was positively to visuospatial working memory and that this positive relationship was associated with more rapid cognitive processing during the manipulation stage, with little or no relationship between PA and the memory storage stage of visuospatial working memory.

Spatial and Visual Reasoning: Do These Abilities Improve in First-Year Veterinary Medical Students Exposed to an Integrated Curriculum?

Spatial visualization ability refers to the human cognitive ability to form, retrieve, and manipulate mental models of spatial nature. Visual reasoning ability has been linked to spatial ability. There is currently limited information about how entry-level spatial and visual reasoning abilities may predict veterinary anatomy performance or may be enhanced with progression through the veterinary anatomy content in an integrated curriculum. The present study made use of two tests that measure spatial ability and one test that measures visual reasoning ability in veterinary students: Guay's Visualization of Views Test, adapted version (GVVT), the Mental Rotations Test (MRT), and Raven's Advanced Progressive Matrices Test, short form (RavenT). The tests were given to the entering class of veterinary students during their orientation week and at week 32 in the veterinary medical curriculum. Mean score on the MRT significantly increased from 15.2 to 20.1, and on the RavenT significantly increased from 7.5 to 8.8. When females only were evaluated, results were similar to the total class outcome; however, all three tests showed significant increases in mean scores. A positive correlation between the pre- and post-test scores was found for all three tests. The present results should be considered preliminary at best for associating anatomic learning in an integrated curriculum with spatial and visual reasoning abilities. Other components of the curriculum, for instance histology or physiology, could also influence the improved spatial visualization and visual reasoning test scores at week 32.

Seeing double: 5-month-olds' mental rotation of dynamic, 3D block stimuli presented on dual monitors

Mental rotation (MR) involves the ability to predict how an object will look once it has been rotated into a new orientation in space. To date, studies of MR in infants have tested this ability using abstract stimuli presented using a single display. Evidence from existing studies suggests that using multiple displays may affect an infant's performance in some kinds of MR tasks. This study used Moore & Johnson's (2008) simplified Shepard-Metzler objects in a dual-monitor MR task presented to five-month-old infants. Evidence for MR in infancy was found. These findings have implications for MR testing in infancy and the influence of display properties on infant MR performance.

Spatial Processing in Infancy Predicts Both Spatial and Mathematical Aptitude in Childhood

Despite considerable interest in the role of spatial intelligence in science, technology, engineering, and mathematics (STEM) achievement, little is known about the ontogenetic origins of individual differences in spatial aptitude or their relation to later accomplishments in STEM disciplines. The current study provides evidence that spatial processes present in infancy predict interindividual variation in both spatial and mathematical competence later in development. Using a longitudinal design, we found that children’s performance on a brief visuospatial change-detection task administered between 6 and 13 months of age was related to their spatial aptitude (i.e., mental-transformation skill) and mastery of symbolic-math concepts at 4 years of age, even when we controlled for general cognitive abilities and spatial memory. These results suggest that nascent spatial processes present in the first year of life not only act as precursors to later spatial intelligence but also predict math achievement during childhood.

Infants Prefer Female Body Phenotypes; Infant Girls Prefer They Have an Hourglass Shape

Adolescents and adults show preferences for male and female body shapes consistent with evolutionary theories of reproductive fitness and mate selection. However, when these preferences for females with narrow waists (i.e., 0.7 waist-to-hip ratio) and men with broad shoulders (i.e., mesomorphic body shape) emerge during the lifespan is largely unknown. To address this knowledge gap, eye-movements were tracked in 146 infants (3-18 months of age) during computer presentation of three-dimensional human figures varying in body features thought relevant for reproductive success (e.g., secondary sex characteristics, waist-to-hip ratio). When presented with pairs of figures differing in apparent sex, male and female infants looked significantly longer at the female figure compared to the male figure, a new finding that extends previous research showing preferences for female faces in infancy. When presented with same-sex figures differing in characteristics associated with mate value, male and female infants looked longer at a low mate value male (i.e., an endomorphic body type) compared to a high mate value male (i.e., a mesomorphic body type), a finding that replicates the results of previous research. In addition, the novel use of high and low mate value female figures showed a sex difference in visual attention, such that female infants looked longer at the high mate value female figure compared to the low mate female figure whereas male infants showed the opposite pattern of results. In sum, these findings suggest that infants generally do not possess preferences for adult-defined attractive male body shapes. However, infant girls' greater attention to a female figure with an adult-preferred waist-to-hip ratio raises the possibility that evolved preferences for 0.7 waist-to-hip ratio influence girls' later preference for toys representing females with an hourglass shape, perhaps supporting elaboration of adult social behaviors that enhance reproductive success (e.g., cooperative breeding).

You Should Be the Specialist! Weak Mental Rotation Performance in Aviation Security Screeners - Reduced Performance Level in Aviation Security with No Gender Effect

Aviation security screeners analyze a large number of X-ray images per day and seem to be experts in mentally rotating diverse kinds of visual objects. A robust gender-effect that men outperform women in the Vandenberg & Kuse mental rotation task has been well documented over the last years. In addition it has been shown that training can positively influence the overall task-performance. Considering this, the aim of the present study was to investigate whether security screeners show better performance in the Mental Rotation Test (MRT) independently of gender. Forty-seven security screeners of both sexes from two German airports were examined with a computer based MRT. Their performance was compared to a large sample of control subjects. The well-known gender-effect favoring men on mental rotation was significant within the control group. However, the security screeners did not show any sex differences suggesting an effect of training and professional performance. Surprisingly this specialized group showed a lower level of overall MRT performance than the control participants. Possible aviation related influences such as secondary effects of work-shift or expertise which can cumulatively cause this result are discussed.