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This paper presents an experimental study of participants' response to the sudden appearance of a fire emergency in a virtual environment (VE) and of the adaptivity of their response pattern. A VE has been built in which participants meet two situations: first an explorative navigation and afterwards a hurried escape from the unexpected outbreak of fire. Fire intensity and participants' distance from the exit at the outbreak of fire have been varied as well, to create different degrees of danger and different degrees of difficulty in the task of leaving the premises. Participants' action has been collected automatically for quantitative analysis by registering each individual activation of the interaction devices (a triple button joystick). In addition, the movements in both virtual and real environment of additional groups of participants have been videorecorded for qualitative analysis. Results show that the appearance of the fire emergency triggers important changes in the way people move in the VE, and that such changes are all adaptive responses to an emergency situation. In conclusion, people show recognition of a dangerous situation in a VE and readily produce adaptive responses, making the VE suitable for emergency simulations and for use as an effective training tool. [ABSTRACT FROM AUTHOR]

Previous studies found mental representations of route descriptions north-up oriented when egocentric experience (given by the protagonist's initial view) was congruent with the global reference system. This study examines: (a) the development and maintenance of representations derived from descriptions when the egocentric and global reference systems are congruent or incongruent; and (b) how spatial abilities modulate these representations. Sixty participants (in two groups of 30) heard route descriptions of a protagonist's moves starting from the bottom of a layout and headed mainly northwards (SN description) in one group, and headed south from the top (NS description, the egocentric view facing in the opposite direction to the canonical north) in the other. Description recall was tested with map drawing (after hearing the description a first and second time; i.e. Time 1 and 2) and South-North (SN) or North-South (NS) pointing tasks; and spatial objective tasks were administered. The results showed that: (a) the drawings were more rotated in NS than in SN descriptions, and performed better at Time 2 than at Time 1 for both types of description; SN pointing was more accurate than NS pointing for the SN description, while SN and NS pointing accuracy did not differ for the NS description; (b) spatial (rotation) abilities were related to recall accuracy for both types of description, but were more so for the NS ones. Overall, our results showed that the way in which spatial information is conveyed (with/without congruence between the egocentric and global reference systems) and spatial abilities influence the development and maintenance of mental representations.

Purpose: To evaluate the efficacy and safety of percutaneous treatment of Civinini-Morton's syndrome due to solitary Morton's neuroma and analyze the effect of clinico-demographic factors on outcome., Materials and Methods: Alcohol injection was performed under sonographic guidance in 220 consecutive patients. Pain intensity using a numerical rating scale (NRS), pain features, limitation of everyday activities and comorbidity with other forefoot conditions were evaluated at presentation. Patients were reassessed for symptoms and the need of rescue therapy with neurectomy after a mean follow-up of 19.0 months (range 15-24)., Results: We treated 220 patients (33 males, mean age 55.8 years). Neuromas were located in the III intermetatarsal space in 85.5 %, with a mean size of 5.4 mm. When considering a reduction of pain intensity of ≥50 % of NRS or a complete disappearance of the neuropathic features as a satisfactory clinical response, a 72.3 % (p < 0.001) responder rate was obtained, and only three patients relapsed (1.2 %). An improvement in limitation of everyday activities was observed in 88.6 % (p < 0.001). No influence of clinico-demographic variables on outcome was found. No major complications occurred. Patients with unsatisfactory response had an overload-related comorbid condition in 20/61 (32.8 %). Surgery was later performed in 14 non-responder patients., Conclusions: Ultrasound-guided alcoholization demonstrated a safe profile, relieved neuropathic symptoms in a majority of patients and improved their quality of life. Rescue therapy with surgery is feasible in patients with unsatisfactory response. However, a thorough evaluation for forefoot comorbidities should be obtained, as they may act as confounding factors.

Background: Ultrasonography-guided alcohol injection (USGAI) of Morton's neuroma represents an alternative to operative treatment. Nonetheless, the literature only reports few small studies evaluating the effectiveness of the treatment. The aim of the present retrospective study was to assess the effectiveness of USGAI to treat Morton's neuroma in 508 patients at 2 medical centers., Methods: Between January 2001 and January 2012, 508 patients with 540 Morton's neuroma had USGAI for Morton's neuroma. Only second and third web-space neuromas were included in this study., Results: A mean number of 3.0 (range, 1 to 4) injections were performed for each neuroma. Mean local inflammatory reaction was 0.7 (range, 0 to 2). There were no other local or systemic complications. The overall mean pre-USGAI VAS score was 8.7 (range, 6 to 10), while the post-USGAI VAS score at 1 year was 3.6 (range, 0 to 9). The delta VAS between the pre- and post-USGAI was statistically significant (P < .0001). At 1-year follow-up 74.5% of patients were satisfied with the procedure., Conclusion: USGAI produced encouraging results in over 500 patients affected by Morton's neuroma. The procedure proved to be safe in all patients., Level of Evidence: Level IV, retrospective case series., (© The Author(s) 2014.)

A crucial factor contributing to the high rate of road accidents involving young people is inexperience, in particular the inability to promptly identify risky situations. The aim of this study is to test the effectiveness of a riding simulator in improving this skill in young inexperienced riders. We use the first fixation latency to measure the improvement in detecting the hazardous object. Results show that four training sessions can significantly affect promptness in detecting new hazardous objects as they appear, decreasing the time needed to orient the eyes to the hazard.

The literature reports mixed results on the imagery abilities of the blind, at times showing a difference between sighted and blind individuals and at other times similarities. However, the possibility that the results are due to different strategies spontaneously used in performing the imagery tasks has never been systematically studied. A large group of 30 totally congenitally blind (TCB) individuals and a group of 30 sighted individuals matched for gender age and schooling were presented with a mental pathway task on a complex two-dimensional (5 x 5) matrix. After administering the task, participants were interviewed in order to establish the strategy they used. Results showed that both sighted and TCB may use a spatial mental imagery, a verbal or a mixed strategy in carrying out the task. Differences between the groups emerged only when last location and then entire pathway had to be remembered rather than just the last position, and were clearly affected by the type of strategy. Specifically, TCB performed more poorly than the sighted individuals when they used a spatial mental imagery strategy, whereas the two groups had a similar performance with a verbal strategy.

Background: Charcot neuroarthropathy is a serious complication associated with diabetic neuropathy. This complication probably is most serious when the ankle is involved because of the instability and progressive deformity, which often leads to ulceration, osteomyelitis, and amputation. Arthrodesis before the ulcerated lesion appears is considered a limb salvage treatment. One of the most effective techniques for an unstable ankle in Charcot neuroarthropathy is retrograde transcalcaneal nailing., Methods: Eighteen diabetic patients, without a history of ulceration, were treated from July, 2003, to November, 2005, with panarthrodesis of the ankle using intramedullary retrograde transcalcaneal nailing. The average follow up was 14 +/- 10.1 months. All patients completed the unloaded postoperative period with a fiberglass cast (3 months nonweightbearing and 3 months partial weightbearing) and commenced walking in shoes with a stiff rocker sole and a molded insole., Results: During the followup period there were no major complications. In three patients, removal of one of the proximal screws used for anchoring the nail to the tibia was done because of protrusion causing skin breakdown. Fourteen patients had a stable fusion and four patients had fibrous union. The percentage of limb salvage was 100% in the followup period., Conclusions: Our study confirms that this operative technique is effective and safe.