Human veering while walking blindfolded or walking straight without any visual cues has been widely studied over the last 100 years, but the results are still controversial. The present study attempted to describe and understand the human ability to maintain the direction of a trajectory while walking without visual or audio cues with reference to a proposed mathematical model and using data collected by a global positioning system (GPS). Fifteen right-handed people of both genders, aged 18-30 years, walked without vision in an open field directly toward a target after seeing it for a brief period of time. Time and distance were directly measured by the GPS receiver. The mathematical analysis indicated that both linear and angular velocities determined the shape of the trajectory. Careful observation of the trajectories clearly showed a geometrical pattern, and the circular trajectory was the most frequent. Such behavior can be explained by the almost constant linear and angular velocity during the walk. From the perspective of the mathematical model, angular velocity is the observable physical quantity that most determines the trajectory pattern. One can notice that better performance (i.e., lower angular velocity) is related to longer distances when comparing an individual's circular trajectory walking performance as a function of different target distances (i.e., 30.00, 41.60, 57.69, and 80.00 m).

Este artigo apresenta uma revisão teórica sobre três fatores que podem influenciar no julgamento da atratividade facial: cuidado parental, fatores psicológicos e percepção da dominância, todos relacionados às diferenças individuais. Discute-se se eles afetam os resultados de estudos que envolvam percepção facial, de modo a refutar a hipótese dos hormônios como os maiores influenciadores no julgamento da atratividade. Encontrar as possíveis variáveis que influenciam a atratividade facial pode ajudar a explicar os resultados controversos, além de ampliar o conhecimento sobre a escolha do parceiro.

This paper is about a review on three factors that may affect the judgment of facial attractiveness: parenting care, psychological factors and dominance. They are all related to individual differences. It is discussed whether they may affect the results of studies involving face perception, refuting the hypothesis that hormones have major influence in attractiveness judgments. Finding possible variables that influence facial attractiveness may help to explain the controversial results in this area broadening our understanding about mate choice.

Two models of brain asymmetry in emotional processing were reviewed: the right hemisphere and the valence hypotheses. The first states a dominant role for the right hemisphere in emotional processing, whereas the second assumes that the left hemisphere is dominant for positive emotions and the right hemisphere for negative ones. Different methods, such as the divided visual field technique, have supported both hypotheses. The amygdala and the prefrontal cortex are presented as important structures involved on brain asymmetry in emotional processing. The paper ends pointing out new perspectives for the study of the neural subtrates of different components of emotions.

A sombra de um quadrado projetada ortograficamente sobre uma superfície plana foi investigada como indicadora de profundidade percebida. A sombra foi simulada por computador em cinco posições, relativas ao ângulo de incidência da luz, em cada quadrante da tela do monitor. Os resultados indicaram que as magnitudes das estimativas de profundidade aumentam em função da área exposta da sombra nos casos em que a mesma é parcialmente ocluída. No caso em que a sombra não é ocluída, fatores perceptivos e cognitivos podem afetar as estimativas de profundidade.

The cast shadow of a flat square was depicted on a computer screen by orthografic projection, and investigated as a perceived depth cue. The shadow was projected to five positions relative to the incidence of the light in each quadrant of the screen. Five adults participated in the experiment. Results indicated that the magnitude of the depth estimates increased as a function of the exposed shadow area when the same was partially ocluded. In the conditions in which the shadow was not ocluded, perceptual and cognitive factor can bias the depth estimates.