Premenstrual syndrom

Premenstrual syndrome is a condition with cyclical mood changes occurring in 30 % of the female population of fertile ages. The symptom development is very closely related to the luteal phase indicating the existence of one or more factors during the luteal phase that provoke mental symptoms in sensitive patients. This is further supported by the fact that hysterectomized women with no menstrual bleedings but with the ovarian hormone cycle continue to show cyclical mood changes without having the cycle phase. The nature of the symptom provocating factor is still unknown but the ovarian hormones progesterone and/or estradiol are suspected. This as certain women taking oral contraceptives and sequential postmenopausal estrogen-progestagen treatment achieve mood changes. Psychological and personality factors are probably also involved, at least in the degree of the mood change and the type of mood experienced.     

The Rubber Hand Illusion: two's a company, but three's a crowd

On the one hand, it is often assumed that the Rubber Hand Illusion (RHI) is constrained by a structural body model so that one cannot implement supernumerary limbs. On the other hand, several recent studies reported illusory duplication of the right hand in subjects exposed to two adjacent rubber hands. The present study tested whether spatial constraints may affect the possibility of inducing the sense of ownership to two rubber hands located side by side to the left of the subject's hand. We found that only the closest rubber hand appeared both objectively (proprioceptive drift) and subjectively (ownership rating) embodied. Crucially, synchronous touch of a second, but farther, rubber hand disrupted the objective measure of the RHI, but not the subjective one. We concluded that, in order to elicit a genuine RHI for multiple rubber hands, the two rubber hands must be at the same distance from the subject's hand/body.     

Studying the neural bases of prism adaptation using fMRI: A technical and design challenge

Prism adaptation induces rapid recalibration of visuomotor coordination. The neural mechanisms of prism adaptation have come under scrutiny since the observations that the technique can alleviate hemispatial neglect following stroke, and can alter spatial cognition in healthy controls. Relative to non-imaging behavioral studies, fMRI investigations of prism adaptation face several challenges arising from the confined physical environment of the scanner and the supine position of the participants. Any researcher who wishes to administer prism adaptation in an fMRI environment must adjust their procedures enough to enable the experiment to be performed, but not so much that the behavioral task departs too much from true prism adaptation. Furthermore, the specific temporal dynamics of behavioral components of prism adaptation present additional challenges for measuring their neural correlates. We developed a system for measuring the key features of prism adaptation behavior within an fMRI environment. To validate our configuration, we present behavioral (pointing) and head movement data from 11 right-hemisphere lesioned patients and 17 older controls who underwent sham and real prism adaptation in an MRI scanner. Most participants could adapt to prismatic displacement with minimal head movements, and the procedure was well tolerated. We propose recommendations for fMRI studies of prism adaptation based on the design-specific constraints and our results.     

Poor hand-pointing to sounds in right brain-damaged patients: not just a problem of spatial-hearing

We asked 22 right brain-damaged (RBD) patients and 11 elderly healthy controls to perform hand-pointing movements to free-field unseen sounds, while modulating two non-auditory variables: the initial position of the responding hand (left, centre or right) and the presence or absence of task-irrelevant ambient vision. RBD patients suffering from visual neglect, unlike RBD patients without neglect and healthy controls, showed a systematic rightward error in sound localisation, which was modulated by the non-auditory variables. Localisation errors were exacerbated by initial hand-position to the right of the body-midline, and reduced by the leftwards initial hand-position. Moreover, for the visual neglect patients, mere presence of ambient vision worsened localisation errors. These results demonstrate that although hand-pointing to sounds has often been considered a straightforward approach to investigate sound-localisation abilities in brain-damaged patients, in some patients it may actually reveal localisation deficits that reflect a combination of impaired spatial-hearing and spatial biases from other sensory modalities (i.e., vision and proprioception).     

A comparative study on the flow experience in web-based and text-based interaction environments

The purpose of this study was to explore a substantial phenomenon related to flow experiences (immersion) in text-based interaction systems. Most previous research emphasizes the effects of challenge/skill, focused attention, telepresence, web characteristics, and systems' interface design on users' flow experiences in online environments. However, text-based interaction systems without telepresence features and web characteristics still seem to create opportunities for flow experience. To explore this phenomenon, this study incorporates subject involvement and interpersonal interaction as critical antecedents into the model of flow experience, as well as considers the existence of telepresence. Results reveal that subject involvement, interpersonal interaction, and interactivity speed are critical to focused attention, which enhances users' immersion. With regard to the effect of telepresence, the perceived attractiveness of the interface is a significant facilitator determining users' immersion in web-based, rather than in text-based, interaction environments. Interactivity speed is unrelated to immersion in both web-based and text-based interaction environments. The influence of interpersonal involvement is diminished in web-based interaction environments. The implications and limitations of this study are discussed.     

The Impact of Conflict Issues on Fixed-Pie Perceptions, Problem Solving, and Integrative Outcomes in Negotiation

It is argued that a negotiator's fixed-pie perception, cooperative motivation, problem-solving behavior, and integrative outcomes are influenced by the content of the negotiation—the conflict issue. Negotiation involves conflicting interests, conflicting ideas about intellective problems, or conflicting ideas about evaluative problems. Study 1 showed that individuals in a negotiation about interests have a stronger fixed-pie perception and have a lower cooperative motivation than individuals in an evaluative negotiation, with intellective negotiations taking an intermediate position. Study 2 showed that individuals in a negotiation about interests made more trade-offs and reached higher joint outcomes than individuals in an intellective or evaluative negotiation. Study 3 replicated this finding in a field study. The studies bridge insights from negotiation research and decision-making research and show that the conflict issue has important effects on the negotiation process.