Similar effects of attention directed to acoustic and tactile stimuli on prepulse inhibition of acoustic startle

Prepulse inhibition (PPI) is assumed to index automatic and controlled processing. In three experiments (n= 32, 22, and 30) participants were asked to judge the duration of a prepulse in comparison with a stimulus presented 4000 ms before the prepulse. A distracter was presented simultaneously with the prepulse to increase the cognitive demands of the task. PPI was assessed at stimulus onset asynchronies (SOAs) of 30-150 ms, and 420 ms. The prepulse was either a tone (60 dB) or a tactile stimulus (21 kPa), and startle was elicited by 95 dB white noise. Directing attention to the prepulse increased PPI at SOAs of 60 ms and longer in all experiments, but the sensory modality to which attention was directed played only a minor role. We conclude that directing attention to both acoustic and tactile prepulses increased PPI.     

Intensional Completeness in an Extension of Gödel/Dummett Logic

We enrich intuitionistic logic with a lax modal operator and define a corresponding intensional enrichment of Kripke models M = (W, , V) by a function T giving an effort measure T(w, u) {} for each -related pair (w, u). We show that embodies the abstraction involved in passing from true up to bounded effort to true outright. We then introduce a refined notion of intensional validity M |= p : and present a corresponding intensional calculus iLC-h which gives a natural extension by lax modality of the well-known G: odel/Dummett logic LC of (finite) linear Kripke models. Our main results are that for finite linear intensional models L the intensional theory iTh(L) = {p : | L |= p : } characterises L and that iLC-h generates complete information about iTh(L).Our paper thus shows that the quantitative intensional information contained in the effort measure T can be abstracted away by the use of and completely recovered by a suitable semantic interpretation of proofs.     

Influence of vestibular signals on bodily self-consciousness: Different sensory weighting strategies based on visual dependency

Previous studies showed that the vestibular system is crucial for multisensory integration, however, its contribution to bodily self-consciousness more specifically on full-body illusions is not well understood. Thus, the current study examined the role of visuo-vestibular conflict on a full-body illusion (FBI) experiment that was induced during a supine body position. In a mixed design experiment, 56 participants underwent through a full-body illusion protocol. During the experiment, half of the participants received synchronous visuo-tactile stimulation, and the other half received asynchronous visuo-tactile stimulation, while their physical body was lying in a supine position, but the virtual body was standing. Additionally, the contribution of individual sensory weighting strategies was investigated via the Rod and Frame task (RFT), which was applied both before (pre-FBI standing and pre-FBI supine) and after the full-body illusion (post-FBI supine) protocol. Subjective reports of the participants confirmed previous findings suggesting that there was a significant increase in ownership over a virtual body during synchronous visuo-tactile stimulation. Additionally, further categorization of participants based on their visual dependency (by RFT) showed that those participants who rely more on visual information (visual field dependents) perceived the full-body illusion more strongly than non-visual field dependents during the synchronous visuo-tactile stimulation condition. Further analysis provided not only a quantitative demonstration of full-body illusion but also revealed changes in perceived self-orientation based on their field dependency. Altogether, findings of the current study make further contributions to our understanding of the vestibular system and brought new insight for individual sensory weighting strategies during a full-body illusion.     

Tactile encoding of directions and temporal distances to safety hazards supports drivers in overtaking and intersection scenarios

Safe traffic participation requires continuous monitoring of the environment for potential safety hazards. Here we investigate, to what extent an interface using directed tactile stimuli to communicate temporal distances to approaching objects can make drivers feel supported and influence their driving safety. In contrast to previous studies, we focus on conditions in which the driver has relatively high levels of control over the criticality of evolving hazards as well as on scenarios with laterally approaching hazards. In a dynamic driving simulator experiment, 33 participants completed a selection of overtaking and intersection scenarios with and without sensory support. Furthermore, two novel variants of the interface which differed in the resolution of the temporal distance encoding were utilized. We measured safety, quantified as minimum time-to-contact (mTTC) and rate of critical situations, and assessed the participants’ subjective understanding, acceptance and perceived helpfulness of the support functions. Participants understood the system in both variants after brief exposure. The subjective evaluation was positive with regard to helpfulness, acceptance, and custom questionnaire responses. While mTTC values did not differ between supported and baseline drives, the availability of the system reduced the occurrence of safety–critical situations in intersection scenarios. Driving statistics further reveal that the availability of the system increased the likelihood for entering system-relevant signaling ranges in overtaking scenarios. In sum, the presented work extends previous findings by showing that the subjective utility of the investigated tactile interface applies beyond critical situations and that it can also provide a safety advantage at intersections.     

Beyond Beauty: Design Symmetry and Brand Personality

Our research explores connections between a fundamental element of visual design, namely symmetry, and consumer inferences regarding brand personality. In contrast to prior work focused on broad affective responses, we propose that symmetry plays an additional, nuanced role in the communication of brand personality. Results of four experiments reveal that asymmetry in visual brand elements is associated by consumers with brand excitement, and that the effect is driven in part by the experience of subjective arousal. These findings contribute to growing interest in visual design and consumer processing, while extending current understanding regarding the communication of brand personality.     

Generalization of skills between operant control and discrimination of EEG alpha

While biofeedback is often said to increase self-control of physiological states by increasing awareness of their subjective correlates, relatively few studies have analyzed the relationship between control (standard biofeedback) and awareness (a discrimination paradigm). We hypothesized that the two skills would generalize and facilitate each other for 8–12 Hz EEG amplitude (alpha). Participants were given 7 sessions of training to either control or discriminate Pz alpha followed by 3 sessions of the other paradigm. Another group was given 7 sessions with time divided equally between the two types of training. The control-training first group showed significant generalization of skills to the discrimination task. However, the reverse was not true, and the combined task group did no better in either task than the other two groups. These results provide ambivalent support for the role of awareness in biofeedback, and suggest possible improvements in the discrimination paradigm.     

Reducing postural sway by concurrently performing challenging cognitive tasks

The present experiment varied cognitive complexity and sensory modality on postural control in young adults. Seventeen participants (23.71 ± 1.99 years) were instructed to stand feet together on a force platform while concurrently performing cognitive tasks of varying degrees of difficulty (easy, moderate and difficult). The cognitive tasks were presented both, auditorily and visually. Auditory tasks consisted of counting the occurrence of one or two letters and repeating a string of words. Visual tasks consisted of counting the occurrence of one or two numbers. With increasing cognitive demand, area of 95% confidence ellipse and ML sway variability was significantly reduced. The visual tasks reduced ML sway variability, whereas the auditory tasks increased COP irregularity. We suggest that these findings are primarily due to an increase in sensorimotor integration as a result of a shift in attentional focus.     

A teleological account of Cartesian sensations?

Alison Simmons, in Simmons (1999), argues that Descartes in Meditation Six offered a teleological account of sensory representation. According to Simmons, Descartes’ view is that the biological function of sensations explains both why sensations represent what they do (i.e., their referential content) and why they represent their objects the way they do (i.e., their presentational content). Moreover, Simmons claims that her account has several advantages over other currently available interpretations of Cartesian sensations. In this paper, I argue that Simmons’ teleological account cannot be sustained for both theoretical and textual reasons and that it does not have the advantages it is claimed to have.     

Crossmodal change blindness between vision and touch

Change blindness is the name given to people's inability to detect changes introduced between two consecutively-presented scenes when they are separated by a distractor that masks the transients that are typically associated with change. Change blindness has been reported within vision, audition, and touch, but has never before been investigated when successive patterns are presented to different sensory modalities. In the study reported here, we investigated change detection performance when the two to-be-compared stimulus patterns were presented in the same sensory modality (i.e., both visual or both tactile) and when one stimulus pattern was tactile while the other was presented visually or vice versa. The two to-be-compared patterns were presented consecutively, separated by an empty interval, or else separated by a masked interval. In the latter case, the masked interval could either be tactile or visual. The first experiment investigated visual-tactile and tactile-visual change detection performance. The results showed that in the absence of masking, participants detected changes in position accurately, despite the fact that the two to-be-compared displays were presented in different sensory modalities. Furthermore, when a mask was presented between the two to-be-compared displays, crossmodal change blindness was elicited no matter whether the mask was visual or tactile. The results of two further experiments showed that performance was better overall in the unimodal (visual or tactile) conditions than in the crossmodal conditions. These results suggest that certain of the processes underlying change blindness are multisensory in nature. We discuss these findings in relation to recent claims regarding the crossmodal nature of spatial attention.