Sharing the Space With the "Victim" Can Increase Help Rates. A Study With Virtual Reality.

A typical protocol for the psychological study of helping behavior features two core roles: a help seeker suffering from some personal or situational emergency (often called "victim") and a potential helper. The setting of these studies is such that the victim and the helper often share the same space. We wondered whether this spatial arrangement might affect the help rate. Thus, we designed a simple study with virtual reality in which space sharing could be manipulated. The participant plays the role of a potential helper; the victim is a humanoid located inside the virtual building. When the request for help is issued, the participant can be either in the same spatial region as the victim (the virtual building) or outside it. The effect of space was tested in two kinds of emergencies: a mere request for help and a request for help during a fire. The analysis shows that, in both kinds of emergencies, the participants were more likely to help the victim when sharing the space with it. This study suggests controlling the spatial arrangement when investigating helping behavior. It also illustrates the expediency of virtual reality to further investigate the role of space on pro-social behavior during emergencies.

Driving with Intuition: A Preregistered Study about the EEG Anticipation of Simulated Random Car Accidents.

The study of neural pre-stimulus or "anticipatory" activity opened a new window for understanding how the brain actively constructs the forthcoming reality. Usually, experimental paradigms designed to study anticipatory activity make use of stimuli. The purpose of the present study is to expand the study of neural anticipatory activity upon the temporal occurrence of dichotomic, statistically unpredictable (random) stimuli within an ecological experimental paradigm. To this purpose, we used a simplified driving simulation including two possible, randomly-presented trial types: a car crash end trial and a no car crash end trial. Event Related Potentials (ERP) were extracted -3,000 ms before stimulus onset. We identified a fronto-central negativity starting around 1,000 ms before car crash presentation. By contrast, a whole-scalp distributed positivity characterized the anticipatory activity observed before the end of the trial in the no car crash end condition. The present data are in line with the hypothesis that the brain may also anticipate dichotomic, statistically unpredictable stimuli, relaying onto different pre-stimulus ERP activity. Possible integration with car-smart-systems is also suggested.

Environment learning using descriptions or navigation: The involvement of working memory in young and older adults.

This study examined age-related differences between young and older adults in the involvement of verbal and visuo-spatial components of working memory (WM) when paths are learned from verbal and visuo-spatial inputs. A sample of 60 young adults (20-30 years old) and 58 older adults (60-75 years old) learned two paths from the person's point of view, one displayed in the form of a video showing the path, the other presenting the path in a verbal description. During the learning phase, participants concurrently performed a verbal task (articulatory suppression, AS group), or a visuo-spatial task (spatial tapping, ST group), or no secondary task (control, C group). After learning each path, participants completed tasks that involved the following: (1) recalling the sequential order and the location of landmarks; and (2) judging spatial sentences as true or false (verification test). The results showed that young adults outperformed older adults in all recall tasks. In both age groups performance in all types of task was worse in the AS and ST groups than in the C group, irrespective of the type of input. Overall, these findings suggest that verbal and visuo-spatial components of WM underpin the processing of environmental information in both young and older adults. The results are discussed in terms of age-related differences and according to the spatial cognition framework.

Does psychophysiological predictive anticipatory activity predict real or future probable events?

BACKGROUND: The possibility of predicting random future events before any sensory clues by using human physiology as a dependent variable has been supported by the meta-analysis of Moss-bridge et al. (2012)(1) and recent findings by Tressoldi et al. (2011 and 2013)(2,3) and Mossbridge et al. (2014)(4) defined this phenomenon predictive anticipatory activity (PAA). AIM OF THE STUDY: From a theoretical point of view, one interesting question is whether PAA is related to the effective, real future presentation of these stimuli or whether it is related only to the probability of their presentation. METHODS: This hypothesis was tested with four experiments, two using heart rate and two using pupil dilation as dependent variables. RESULTS: In all four experiments, both a neutral stimulus and a potentially threatening stimulus were predicted 7-10% above chance, independently from whether the predicted threatening stimulus was presented or not. CONCLUSION: These findings are discussed with reference to the "grandfather paradox," and some candidate explanations for this phenomena are presented.

Label-free fluorescence detection of kinase activity using a gold nanoparticle based indicator displacement assay.

A straightforward indicator-displacement assay (IDA) has been developed for the quantitative analysis of ATP→ADP conversion. The IDA relies on the use of gold nanoparticles passivated with a monolayer of thiols terminating with a 1,4,7-triazacyclononane (TACN)·Zn(2+) head group. The analytes ATP and ADP compete to a different extent with a fluorescent probe for binding to the monolayer surface. In the presence of ATP the fluorescent probe is free in solution, whereas in the presence of ADP the fluorescent probe is captured by the nanoparticles and its fluorescence is quenched. The linear response of the fluorescence signal towards different ratios of ATP : ADP permitted the detection of protein kinase activity simply by adding aliquots of the enzyme solution to the assay solution followed by measurement of the fluorescent intensity. The assay poses no restrictions on the target kinase nor does it require labeling of the kinase substrate. The assay was tested on the protein kinases PIM-1 and Src and validated through a direct comparison with the classical radiometric assay using the [γ-(32)P]-labeled ATP.

An exploratory fNIRS study with immersive virtual reality: a new method for technical implementation.

For over two decades Virtual Reality (VR) has been used as a useful tool in several fields, from medical and psychological treatments, to industrial and military applications. Only in recent years researchers have begun to study the neural correlates that subtend VR experiences. Even if the functional Magnetic Resonance Imaging (fMRI) is the most common and used technique, it suffers several limitations and problems. Here we present a methodology that involves the use of a new and growing brain imaging technique, functional Near-infrared Spectroscopy (fNIRS), while participants experience immersive VR. In order to allow a proper fNIRS probe application, a custom-made VR helmet was created. To test the adapted helmet, a virtual version of the line bisection task was used. Participants could bisect the lines in a virtual peripersonal or extrapersonal space, through the manipulation of a Nintendo Wiimote ® controller in order for the participants to move a virtual laser pointer. Although no neural correlates of the dissociation between peripersonal and extrapersonal space were found, a significant hemodynamic activity with respect to the baseline was present in the right parietal and occipital areas. Both advantages and disadvantages of the presented methodology are discussed.

Effects of aging on interference control in selective attention and working memory.

Working memory decay in advanced age has been attributed to a concurrent decrease in the ability to control interference. The present study contrasted a form of interference control in selective attention that acts upon the perception of external stimuli (access) with another form that operates on internal representations in working memory (deletion), in order to determine both of their effects on working memory efficiency in younger and older adults. Additionally, we compared memory performance under these access and deletion functions to performance in their respective control conditions. The results indicated that memory accuracy improved in both age groups from the access functions, but that only young adults benefited from the deletion functions. In addition, intrusion effects in the deletion condition were larger in older than in younger adults. The ability to control the irrelevant perception- and memory-elicited interference did not decline in general with advancing age; rather, the control mechanisms that operate on internal memory representations declined specifically.

Saliency from orthogonal velocity component in texture segregation.

We found that a moving target line, more-vertical than 45 deg-oriented background lines, pops-out (d'=1.2) although it moves at the same speed of background elements and although it is invisible in static presentation (d'=.7). We suggest that the moving more-vertical target is more salient because the motion system responds to the orthogonal-velocity-component (V(perpendicular)=Delta d/Delta t sin theta) that is larger for the more-vertical target than for distracters. However, motion does not produce high d' when the target is more horizontal than background (d'=.6). This result is not expected if saliency resulted from the sum of saliency of orientation and motion independently coded but is instead predicted by visual search asymmetry. A line length effect on the moving target saliency also suggests that V(perpendicular) is extracted on the whole line and this operation is facilitated by line length in the same way for more-vertical and more-horizontal targets. Altogether, these results demonstrate that speed-based segmentation operating on V(perpendicular) not only affects speed and direction of motion discrimination, as previously demonstrated, but accounts for high saliency of image features that would otherwise prove undetectable of the basis of orientation-contrast.