A new effect of luminance gradient on achromatic simultaneous contrast

A new effect in the domain of achromatic simultaneous contrast has been observed. A middle gray region placed at the center of an area filled by a linear achromatic gradient from black (outer part) to white (inner part) is perceived as being much darker than an identical middle gray region surrounded by a reversed gradient. By using a matching task in two experiments, it has been shown that this phenomenon is much stronger than the classical achromatic simultaneous contrast effect. The new effect is interpreted in terms of thealbedo hypothesis.     

Perceptual organization overcomes the effects of local surround in determining simultaneous lightness contrast

Lightness induction can occur on the basis of the immediate surround of a region (local interactions) and also on the basis of global factors of perceptual organization. The experiments reported in this article used novel displays that made it possible to differentiate the contributions of these two kinds of factors. The experiments demonstrated, for the first time, that when higher-level factors act contemporaneously with lower-level factors, the contrast effect induced by the global-organization principle of perceptual belongingness overcomes the effect due to retinal lateral inhibition.     

The importance of gestural communication: a study of human–dog communication using incongruent information

We assessed how water rescue dogs, which were equally accustomed to respond to gestural and verbal requests, weighted gestural versus verbal information when asked by their owner to perform an action. Dogs were asked to perform four different actions (“sit”, “lie down”, “stay”, “come”) providing them with a single source of information (in Phase 1, gestural, and in Phase 2, verbal) or with incongruent information (in Phase 3, gestural and verbal commands referred to two different actions). In Phases 1 and 2, we recorded the frequency of correct responses as 0 or 1, whereas in Phase 3, we computed a ‘preference index’ (percentage of gestural commands followed over the total commands responded). Results showed that dogs followed gestures significantly better than words when these two types of information were used separately. Females were more likely to respond to gestural than verbal commands and males responded to verbal commands significantly better than females. In the incongruent condition, when gestures and words simultaneously indicated two different actions, the dogs overall preferred to execute the action required by the gesture rather than that required verbally, except when the verbal command “come” was paired with the gestural command “stay” with the owner moving away from the dog. Our data suggest that in dogs accustomed to respond to both gestural and verbal requests, gestures are more salient than words. However, dogs’ responses appeared to be dependent also on the contextual situation: dogs’ motivation to maintain proximity with an owner who was moving away could have led them to make the more ‘convenient’ choices between the two incongruent instructions.     

Long Lasting Marriages in Chile

Reports the Chilean segment of a multicultural, multicountry (Canada, Germany, Israel, Netherlands, South Africa, Sweden, USA) study on long-term marriages. This pilot study is seen as a starting point in research focusing on the childhood background and family history of long-term marital partners in Chile. No statistically significant association between marital satisfaction and economic or educational level was found. A positive correlation was found between marital satisfaction and happiness during childhood. Love, trust, and loyalty appear to be the main ingredients of satisfaction for both satisfied and unsatisfied couples. The findings across countries as to the essential ingredients reported here have been remarkably similar.     

Eudaimonic Well-Being in Transsexual People,Before and After Gender Confirming Surgery

Gender confirming surgery (GCS) and cross-sex hormones (CSH) are crucial steps in the self-realization of a transsexual individual. However, no study has analyzed the outcome of GCS in a eudaimonic perspective, nor explored eudaimonic well-being before GCS. The study compares the eudaimonic well-being of trans men (N = 56) and women (N = 89) before and after GCS; in the MtF sample, a further comparison was carried out between those who never started any medical intervention and those who were already taking CSH. Finally, the impact of experiences of harassment, discrimination and violence on eudaimonic well-being in the post-surgery sample was explored. All participants completed the Psychological Well-being Scales (Ryff in J Pers Soc Psychol 57:1069–1081, 1989) and, only the post-surgery sample, a questionnaire to assess previous experiences of harassment, discrimination and violence. Both in MtF and FtM participants, those who already received GCS showed higher scores on self-acceptance; in the MtF sample, higher scores were also found on environmental mastery and lower scores on personal growth. The association between experiences of discrimination on well-being was limited and positive, with higher scores in personal growth only in FtM participants who reported being victims of such experiences. Our results suggest that both MtF and FtM transsexuals show higher levels of eudaimonic well-being after GCS.     

Whole-Body Movements in Long-Term Weightlessness: Hierarchies of the Controlled Variables Are Gravity-Dependent

Switching between contexts affects the mechanisms underlying motion planning, in particular it may entail reranking the variables to be controlled in defining the motor solutions. Three astronauts performed multiple sessions of whole-body pointing, in normogravity before launch, in prolonged weightlessness onboard the International Space Station, and after return. The effect of gravity context on kinematic and dynamic components was evaluated. Hand trajectory was gravity independent; center-of-mass excursion was highly variable within and between subjects. The body-environment effort exchange, expressed as inertial ankle momentum, was systematically lower in weightlessness than in normogravity. After return on Earth, the system underwent a rapid 1-week readaptation. The study indicates that minimizing the control effort is given greater weight when optimizing the motor plan in weightlessness compared to normogravity: the hierarchies of the controlled variables are gravity dependent.     

Bounded stability of the quiet standing posture: an intermittent control model

The paper presents a control model of body sway in quiet standing, which aims at achieving bounded stability by means of an intermittent control mechanism. Control bursts are generated when the current state vector exits an area of uncertainty around the reference point in the phase plane. This area is determined by the limited resolution of proprioceptive signals and the burst generation mechanism is predictive in the sense that it incorporates a rough, but working knowledge (internal model) of the biomechanics of the human inverted pendulum. We show that such a model, in spite of its simplicity and of the fact that it relies on very noisy measurements, is robust and can explain in a detailed way the measured sway patterns.     

Affective interactions using virtual reality: the link between presence and emotions.

Many studies showed the ability of movies and imagery techniques to elicit emotions. Nevertheless, it is less clear how to manipulate the content of interactive media to induce specific emotional responses. In particular, this is true for the emerging medium virtual reality (VR), whose main feature is the ability to induce a feeling of "presence" in the computer-generated world experienced by the user. The main goal of this study was to analyze the possible use of VR as an affective medium. Within this general goal, the study also analyzed the relationship between presence and emotions. The results confirmed the efficacy of VR as affective medium: the interaction with "anxious" and "relaxing" virtual environments produced anxiety and relaxation. The data also showed a circular interaction between presence and emotions: on one side, the feeling of presence was greater in the "emotional" environments; on the other side, the emotional state was influenced by the level of presence. The significance of these results for the assessment of affective interaction is discussed.