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.

     

Mental rotation of cubes with a snake face: The role of the human-body analogy revisited

ABSTRACT

Previous research has demonstrated repeatedly that the mental rotation of human-like objects can be performed more quickly than the mental rotation of abstract objects (a body analogy effect). According to existing accounts, the body analogy effect is mediated by projections of one’s own body axes onto objects (spatial embodiment), and the mental emulation of the observed body posture (motoric embodiment). To test whether motoric embodiment facilitates the mental rotation of human-like objects, we conducted an experiment using a snake-like object that had its own body axes but would be difficult to emulate. Twenty-four participants performed the mental rotation of snake-shaped cubes with or without a snake face as well as human-shaped cubes with or without a human face. Results showed that the presence of a face increased mental rotation speeds for both human-shaped and snake-shaped cubes, confirming both the human-body and snake analogy effects. More importantly, the snake analogy effect was equal to the human-body analogy effect. These findings contradict the motoric embodiment account and suggest that any object that can be regarded as a unit facilitates holistic mental rotation, which in turn leads to improved performance.     

Enhancing Interpretability in Factor Analysis by Means of Mathematical Optimization

Abstract

Exploratory Factor Analysis (EFA) is a widely used statistical technique to discover the structure of latent unobserved variables, called factors, from a set of observed variables. EFA exploits the property of rotation invariance of the factor model to enhance factors’ interpretability by building a sparse loading matrix. In this paper, we propose an optimization-based procedure to give meaning to the factors arising in EFA by means of an additional set of variables, called explanatory variables, which may include in particular the set of observed variables. A goodness-of-fit criterion is introduced which quantifies the quality of the interpretation given this way. Our methodology also exploits the rotational invariance of EFA to obtain the best orthogonal rotation of the factors, in terms of the goodness-of-fit, but making them match to some of the explanatory variables, thus going beyond traditional rotation methods. Therefore, our approach allows the analyst to interpret the factors not only in terms of the observed variables, but in terms of a broader set of variables. Our experimental results demonstrate how our approach enhances interpretability in EFA, first in an empirical dataset, concerning volumes of reservoirs in California, and second in a synthetic data example.     

The influence of juggling on mental rotation performance in children with spina bifida

This study examined the influence of juggling training on mental rotation ability in children with spina bifida. Children between the ages of 8 and 12 solved a chronometric mental rotation test. Half of the children received juggling training (EG) over an 8week time period; the other half did not receive training (CG). Afterwards, all participants completed the mental rotation test again. Children of the EG showed a significant decrease in reaction time and an increase in mental rotation speed compared to the control group. This indicates that juggling improves the rotation in the mental rotation process in children with spina bifida.     

Combining Action Observation and Motor Imagery Improves Eye–Hand Coordination during Novel Visuomotor Task Performance

Abstract

In this study, we compared the effectiveness of concurrent action observation and motor imagery (AO?+?MI), observing with the intent to imitate (active observation; AO), and passive observation (PO) training interventions for improving eye–hand coordination. Fifty participants were assigned to five groups [AO?+?MI, AO, PO, physical practice (PP); control] and performed a visuomotor rotation task, whilst eye movements were recorded. Each participant then performed 20 task trials in a training intervention before repeating the visuomotor rotation task in a post-test. As expected, PP produced the greatest improvement in task performance and eye–hand coordination. However, in comparison to the control group, AO?+?MI training produced a statistically significant increase in both task performance and eye–hand coordination, but no such improvements were found following AO or PO.