Eye movements during long-term pictorial recall

We investigated eye movements during long-term pictorial recall. Participants performed a perceptual encoding task, in which they memorized 16 stimuli that were displayed in different areas on a computer screen. After the encoding phase the participants had to recall and visualize the images and answer to specific questions about visual details of the stimuli. One week later the participants repeated the pictorial recall task. Interestingly, not only in the immediate recall task but also 1week later participants looked longer at the areas where the stimuli were encoded. The major contribution of this study is that memory for pictorial objects, including their spatial location, is stable and robust over tim

Motor imagery training improves precision of an upper limb movement in patients with hemiparesis

BACKGROUND: In healthy participants, beneficial effects of motor imagery training on movement execution have been shown for precision, strength, and speed. In the clinical context, it is still debated whether motor imagery provides an effective rehabilitation technique in patients with motor deficits.OBJECTIVE: To compare the effectiveness of two different types of movement training: motor imagery vs. motor execution.METHODS: Twenty-five patients with hemiparesis were assigned to one of two training groups: the imagery or the execution-training group. Both groups completed a baseline test before they received six training sessions, each of which was followed by a test session. Using a novel and precisely quantifiable test, we assessed how accurately patients performed an upper limb movement. RESULTS: Both training groups improved performance over the six test sessions but the improvement was significantly larger in the imagery group. That is, the imagery group was able to perform more precise movements than the execution group after the sixth training session while there was no difference at the beginning of the training.CONCLUSIONS: The results provide evidence for the benefit of motor imagery training in patients with hemiparesis and thus suggest the integration of cognitive training in conventional physiotherapy practice

Measuring presence with verbal versus pictorial scales: a comparison between online- and ex post-ratings

In this study, we compare subjective online- and post-immersion measures. Although its relevance appears obvious from a theoretical and applied research perspective, this question has not yet been addressed in previous studies. In addition, we also compare verbally and pictorially anchored scales. These factors were measured in different contents using a 2×2×2 design. We manipulated time of measure (online vs. ex post), type of measure (verbal vs. visual), and content (language vs. language-free). Participants (N=162) evaluated two video clips in terms of presence. No differences between averaged online- and post-immersion measures were found and online judgments did not interfere with the sensation of presence. In line with findings from other areas of research, the use of pictorially anchored items has major advantages. Our results suggest that those items require less mental workload and assess the sensation of presence more directly than verbally anchored items. We discuss the theoretical implications of our finding

Denial of Death? Death-Related Words are Suppressed in a Think/No-Think Paradigm

According to terror management theory, humans automatically suppress the thought of death when reminded of their mortality (mortality salience; MS), leading to a hyper- accessibility of death-related thoughts under MS. Here, we tested the claim of automatic death-thought-suppression using a think/no-think paradigm. Participants were reminded of death or a painful tooth treatment (control) before learning word associations between cue words and neutral, negative, or death-related target words. First analyses indicate that in the study phase, participants under MS performed worse in acquiring the target words. In the test phase, these general performance differences disappeared. However, death-related words were generally remembered worse than negative words, but better with multiple attempts of suppression under MS. This effect stands in line with the assumption of suppressed thoughts becoming hyper-accessible. Participants in the control group did remember less death-related words than participants under MS. This effect hints at an automatic thought suppression of death-thoughts

Sharing a Mental Number Line Across Individuals?:The Role of Body Position and Empathy in Joint Numerical Cognition

A growing body of research shows that the human brain acts differently when performing a task together with another person than when performing the same task alone. In this study, we investigated the influence of a co-actor on numerical cognition using a joint random number generation (RNG) task. We found that participants generated relatively smaller numbers when they were located to the left (vs. right) of a co-actor (Experiment 1), as if the two individuals shared a mental number line and predominantly selected numbers corresponding to their relative body position. Moreover, the mere presence of another person on the left or right side or the processing of numbers from loudspeaker on the left or right side had no influence on the magnitude of generated numbers (Experiment 2), suggesting that a bias in RNG only emerged during interpersonal interactions. Interestingly, the effect of relative body position on RNG was driven by participants with high trait empathic concern towards others, pointing towards a mediating role of feelings of sympathy for joint compatibility effects. Finally, the spatial bias emerged only after the co-actors swapped their spatial position, suggesting that joint spatial representations are constructed only after the spatial reference frame became salient. In contrast to previous studies, our findings cannot be explained by action co-representation because the consecutive production of numbers does not involve conflict at the motor response level. Our results therefore suggest that spatial reference coding, rather than motor mirroring, can determine joint compatibility effects. Our results demonstrate how physical properties of interpersonal situations, such as the relative body position, shape seemingly abstract cognition

How to Get There When You Are There Already? Defining Presence in Virtual Reality and the Importance of Perceived Realism

The aim of the current opinion paper is to challenge the current definition of presence in the context of virtual reality (VR). Opticians do not only measure visual acuity but also the visual field, stereoscopic vision, and color vision. In the same vein, presence researchers are encouraged to not only measure the experience of “being there” in the sense of attentional allocation to the virtual environment (VE), but also the perceived realism of the VE. Perceived realism is the result of an evaluation of the virtual world regarding (1) the subjective degree of reality of the depicted environment and (2) its overall plausibility and credibility. Thus, the sense of presence in a VE is conceived as a composite of being there and perceived realism. When in VR, a user will inevitably compare the look of virtual objects to real-world objects and judge the level of congruence (Sutcliffe and Gault, 2004). The user evaluates the plausibility and naturalness of the depicted world as well as the ease of interaction within the VE by answering questions such as: is there a shadow cast? Are the proportions of objects correct? Does the environment correspond to my own movements? Does my virtual body match the proportions of my real body? Just like the visual features, a story and its characters are also evaluated in terms of consistency and plausibility (Park et al., 2010; Gorini et al., 2011): are the consequences of actions plausible? Is the story coherent in itself? Does the causal sequence of events make sense? The answers to these questions define the degree of perceived realism. Perceived realism leads to the experience that a user not only feels surrounded by the VE, but rather has a compelling sense of reality and in extreme cases even forgets that he or she is wearing a head-mounted display (HMD). Previous papers on presence are based on the assumption that realism enhances presence (e.g., Heeter, 1992; Welch et al., 1996; Lombard and Ditton, 1997; Bystrom et al., 1999) suggested a conceptualization of presence as the degree to which a medium seems realistic. Interestingly, perceived realism is nevertheless not part of the most widely used presence definitions. It is either a possible trigger of presence or is blended in with the term being there. The conceptualization of presence as the experience of being there in a mediated environment dominates current presence definitions. Being there is strongly associated with attentional allocation and the sensation of being surrounded and absorbed by a mediated world. However, we claim that presence in VR requires much more than just being there. With the widespread use of immersive VR technology, it has become an easy task to absorb users in a VE. Thus, judgments about the realism of the VE become increasingly important. Being there and perceived realism are both important but yet different aspects of presence. They need to be combined in order to (1) adequately describe and define the experience of presence and (2) to obtain an appropriate and more complete assessment of presence in VR. Thus, theories and measures of presence need to be extended and establish perceived realism as an important domain besides being there. Presence in VR as a Two-Dimen

God is up and devil is down: mortality salience increases implicit spatial-religious associations

Most Christians in Western cultures associate God with upper space and devil with lower space. Measuring this spatial association captures the implicit metaphorical representations of religious concepts. Previous studies have shown that implicit measurements of the belief in God increase when people are confronted with their own mortality. Here we investigated the effect of mortality salience on implicit metaphorical representations of religiosity. Using a repeated measurement design, we found that implicit associations between God-up and devil-down increase when people think about their own death, but not when they think about a tooth treatment (control condition). The effect was moderated by self-esteem; only people with low and medium self-esteem were influenced by mortality salience. Our results show that mortality salience automatically activates religious contents and their cognitive representations that embody these abstract contents

Vestibular thresholds for yaw rotation about an earth-vertical axis as a function of frequency

Perceptual direction detection thresholds for yaw rotation about an earth-vertical axis were measured at seven frequencies (0.05, 0.1, 0.2, 0.5, 1, 2, and 5Hz) in seven subjects in the dark. Motion stimuli consisted of single cycles of sinusoidal acceleration and were generated by a motion platform. An adaptive two-alternative categorical forced-choice procedure was used. The subjects had to indicate by button presses whether they perceived yaw rotation to the left or to the right. Thresholds were measured using a 3-down, 1-up staircase paradigm. Mean yaw rotation velocity thresholds were 2.8degs−1 for 0.05Hz, 2.5degs−1 for 0.1Hz, 1.7degs−1 for 0.2Hz, 0.7degs−1 for 0.5Hz, 0.6degs−1 for 1Hz, 0.4 degs−1 for 2Hz, and 0.6degs−1 for 5Hz. The results show that motion thresholds increase at 0.2Hz and below and plateau at 0.5Hz and above. Increasing velocity thresholds at lower frequencies qualitatively mimic the high-pass characteristics of the semicircular canals, since the increase at 0.2Hz and below would be consistent with decreased gain/sensitivity observed in the VOR at lower frequencies. In fact, the measured dynamics are consistent with a high pass filter having a threshold plateau of 0.71degs-1 and a cut-off frequency of 0.23Hz, which corresponds to a time constant of approximately 0.70s. These findings provide no evidence for an influence of velocity storage on perceptual yaw rotation threshold