The Experts below are selected from a list of 35751 Experts worldwide ranked by ideXlab platform
H.b. Coslett - One of the best experts on this subject based on the ideXlab platform.
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Assessment of spatial attention and neglect with a virtual wheelchair Navigation Task
Journal of clinical and experimental neuropsychology, 2008Co-Authors: L.j. Buxbaum, D. Mastrogiovanni, M.s. Read, E. Rosenberg-pitonyak, Albert Rizzo, Mary Ann Palermo, H.b. CoslettAbstract:A total of 9 participants with right-hemisphere stroke performed a new virtual reality (VR) wheelchair Navigation test of lateralized spatial attention and neglect. The test consists of a virtual path along which participants navigate (or are navigated) as they name virtual objects encountered. There are 4 VR conditions, obtained by crossing the factors array complexity and driver. Participants performed the VR Task, a real-life wheelchair Navigation Task, and a battery of attention and neglect tests. The VR test showed sensitivity to both array complexity and driver, exhibited strong correlations with the wheelchair Navigation test, and detected lateralized attention deficits in mild patients. The VR Task thus shows promise as a sensitive, efficient measure of real-life Navigation.
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Assessment of Spatial Neglect with a Virtual Wheelchair Navigation Task
2006 International Workshop on Virtual Rehabilitation, 2006Co-Authors: L.j. Buxbaum, M. Palermo, D. Mastrogiovanni, M.s. Read, E. Rosenberg-pitonyak, Albert Rizzo, H.b. CoslettAbstract:We report data from 9 participants with right hemisphere stroke on a new virtual reality (VR) wheelchair Navigation test designed to assess lateralized spatial attention and neglect. The test consists of a virtual winding path along which participants must navigate (or be navigated by an experimenter) as they name objects encountered along the way. There are 4 VR Task conditions, obtained by crossing the factors array complexity (simple, complex) and driver (participant, experimenter). Participants performed the VR Task, a real-life wheelchair Navigation Task, and a battery of tests assessing arousal, visual attention under secondary Task demands, and neglect. The VR test showed sensitivity to both array complexity and driver, with best performance occurring in the experimenter-navigated, simple array condition. The VR test also showed high correlations with the wheelchair Navigation test, and these correlations were in many instances higher than those between traditional clinical neglect tests and the wheelchair Navigation Task. Moreover, the VR test detected lateralized attention deficits in participants whose performance was within the normal range on other neglect tests. We conclude that the VR Task is sensitive to factors likely to affect the severity of neglect in the daily environment, and shows promise as an efficient, easily administered measure of real-life wheelchair Navigation
Andinet Enquobahrie - One of the best experts on this subject based on the ideXlab platform.
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development and face validation of a virtual camera Navigation Task trainer
Surgical Endoscopy and Other Interventional Techniques, 2019Co-Authors: Venkata Sreekanth Arikatla, Sam Horvath, Lora A. Cavuoto, Steve Schwaitzberg, Andinet EnquobahrieAbstract:Background The fundamentals of laparoscopic surgery (FLS) trainer box, which is now established as a standard for evaluating minimally invasive surgical skills, consists of five Tasks: peg transfer, pattern cutting, ligation, intra- and extracorporeal suturing. Virtual simulators of these Tasks have been developed and validated as part of the Virtual Basic Laparoscopic Skill Trainer (VBLaST) (Arikatla et al. in Int J Med Robot Comput Assist Surg 10:344–355, 2014; Zhang et al. in Surg Endosc 27(10):3603–3615, 2013; Sankaranarayanan et al. in J Laparoendosc Adv Surg Tech 20(2):153–157, 2010; Qi et al. J Biomed Inform 75:48–62, 2017). The virtual Task trainers have many advantages including automatic real-time objective scoring, reduced costs, and eliminating human proctors. In this paper, we extend VBLaST by adding two camera Navigation system Tasks: (a) pattern matching and (b) path tracing.
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Development and face validation of a virtual camera Navigation Task trainer
Surgical endoscopy, 2018Co-Authors: Venkata Sreekanth Arikatla, Sam Horvath, Lora A. Cavuoto, Steve Schwaitzberg, Andinet EnquobahrieAbstract:The fundamentals of laparoscopic surgery (FLS) trainer box, which is now established as a standard for evaluating minimally invasive surgical skills, consists of five Tasks: peg transfer, pattern cutting, ligation, intra- and extracorporeal suturing. Virtual simulators of these Tasks have been developed and validated as part of the Virtual Basic Laparoscopic Skill Trainer (VBLaST) (Arikatla et al. in Int J Med Robot Comput Assist Surg 10:344-355, 2014; Zhang et al. in Surg Endosc 27(10):3603-3615, 2013; Sankaranarayanan et al. in J Laparoendosc Adv Surg Tech 20(2):153-157, 2010; Qi et al. J Biomed Inform 75:48-62, 2017). The virtual Task trainers have many advantages including automatic real-time objective scoring, reduced costs, and eliminating human proctors. In this paper, we extend VBLaST by adding two camera Navigation system Tasks: (a) pattern matching and (b) path tracing. A comprehensive camera Navigation simulator with two virtual Tasks, simplified and cheaper hardware interface (compared to the prior version of VBLaST), graphical user interface, and automated metrics has been designed and developed. Face validity of the system is tested with medical students and residents from the University at Buffalo's medical school. The subjects rated the simulator highly in all aspects including its usefulness in training to center the target and to teach sizing skills. The quality and usefulness of the force feedback scored the lowest at 2.62.
Veronique D Bohbot - One of the best experts on this subject based on the ideXlab platform.
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modulation of spatial and response strategies by phase of the menstrual cycle in women tested in a virtual Navigation Task
Psychoneuroendocrinology, 2016Co-Authors: Dema Hussain, Kyoko Konishi, Sarah Hanafi, Wayne G Brake, Veronique D BohbotAbstract:Different memory systems are employed to navigate an environment. It has been consistently shown in rodents that estrogen impacts multiple memory system bias such that low estradiol (E2) is associated with increased use of a striatal-mediated response strategy whereas high E2 increases use of a hippocampal-dependent spatial memory. Low E2 also enhances performance on a response-based Task whereas high E2 levels improve learning on a spatial Task. The purpose of the present cross-sectional study was to investigate Navigational strategies in young, healthy, naturally cycling women. Participants were split into either an early follicular (i.e., when E2 levels are low), ovulatory (i.e., when E2 levels are high) or mid/late luteal (i.e., end of the cycle, when E2 levels decrease and progesterone levels rise) phase group, using self-reported date of the menstrual cycle. Serum hormone level measurements (E2, progesterone, testosterone) were used to confirm cycle phase assignment. Participants were administered a verbal memory Task as well as a virtual Navigation Task that can be solved by using either a response or spatial strategy. Women tested in the ovulatory phase, under high E2 conditions, performed better on a verbal memory Task than women tested during the other phases of the cycle. Interestingly, women tested in the mid/late luteal phase, when progesterone is high, predominantly used a spatial strategy, whereas the opposite pattern was observed in the early follicular and ovulatory groups. Our data suggest that the specific memory system engaged differs depending on the phase of the menstrual cycle and may be mediated by both E2 and progesterone, rather than E2 alone.
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decreased functional magnetic resonance imaging activity in the hippocampus in favor of the caudate nucleus in older adults tested in a virtual Navigation Task
Hippocampus, 2013Co-Authors: Kyoko Konishi, Nicole Etchamendy, Aline Marighetto, Natasha Rajah, Veronique D BohbotAbstract:The neuroimaging literature has shown consistent decreases in functional magnetic resonance imaging (fMRI) activity in the hippocampus of healthy older adults engaged in a Navigation Task. However, Navigation in a virtual maze relies on spatial or response strategies known to depend on the hippocampus and caudate nucleus, respectively. Therefore, since the proportion of people using spatial strategies decreases with normal aging, we hypothesized that it was responsible for the observed decreases in fMRI activity in the hippocampus reported in the literature. The aim of this study was to examine the effects of aging on the hippocampus and caudate nucleus during Navigation while taking into account individual Navigational strategies. Young (N = 23) and older adults (N = 29) were tested using fMRI on the Concurrent Spatial Discrimination Learning Task, a radial Task that dissociates between spatial and response strategies (in Stage 2) after participants reached criteria (in Stage 1). Success on Stage 2 requires that participants have encoded the spatial relationship between the target object and environmental landmarks, that is, the spatial strategy. While older adults required more trials, all participants reached criterion. fMRI results showed that, as a group, young adults had significant activity in the hippocampus as opposed to older adults who instead had significant activity in the caudate nucleus. Importantly, individual differences showed that the older participants who used a spatial strategy to solve the Task had significant activity in the hippocampus. These findings suggest that the aging process involves a shift from using the hippocampus toward the caudate nucleus during Navigation but that activity in the hippocampus is sustained in a subset of healthy older adults engaged in spatial strategies. © 2013 Wiley Periodicals, Inc.
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Selective deficit in spatial memory strategies contrast to intact response strategies in patients with schizophrenia spectrum disorders tested in a virtual Navigation Task
Hippocampus, 2013Co-Authors: Leanne K. Wilkins, Kyoko Konishi, Todd A. Girard, Matthew J. King, Katherine A. Herdman, Jelena P. King, Bruce K. Christensen, Veronique D BohbotAbstract:Spatial memory is impaired among persons with schizophrenia (SCZ). However, different strategies may be used to solve most spatial memory and Navigation Tasks. This study investigated the hypothesis that participants with schizophrenia-spectrum disorders (SSD) would demonstrate differential impairment during acquisition and retrieval of target locations when using a hippocampal-dependent spatial strategy, but not a response strategy, which is more associated with caudate function. Healthy control (CON) and SSD participants were tested using the 4-on-8 virtual maze (4/8VM), a virtual Navigation Task designed to differentiate between participants' use of spatial and response strategies. Consistent with our predictions, SSD participants demonstrated a differential deficit such that those who navigated using a spatial strategy made more errors and took longer to locate targets. In contrast, SSD participants who spontaneously used a response strategy performed as well as CON participants. The differential pattern of spatial-memory impairment in SSD provides only indirect support for underlying hippocampal dysfunction. These findings emphasize the importance of considering individual strategies when investigating SSD-related memory and Navigation performance. Future cognitive intervention protocols may harness SSD participants' intact ability to navigate using a response strategy and/or train the deficient ability to navigate using a spatial strategy to improve Navigation and memory abilities in participants with SSD.
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Decreased functional magnetic resonance imaging activity in the hippocampus in favor of the caudate nucleus in older adults tested in a virtual Navigation Task
Hippocampus, 2013Co-Authors: Kyoko Konishi, Nicole Etchamendy, Aline Marighetto, Natasha Rajah, Shumita Roy, Veronique D BohbotAbstract:The neuroimaging literature has shown consistent decreases in functional magnetic resonance imaging (fMRI) activity in the hippocampus of healthy older adults engaged in a Navigation Task. However, Navigation in a virtual maze relies on spatial or response strategies known to depend on the hippocampus and caudate nucleus, respectively. Therefore, since the proportion of people using spatial strategies decreases with normal aging, we hypothesized that it was responsible for the observed decreases in fMRI activity in the hippocampus reported in the literature. The aim of this study was to examine the effects of aging on the hippocampus and caudate nucleus during Navigation while taking into account individual Navigational strategies. Young (N = 23) and older adults (N = 29) were tested using fMRI on the Concurrent Spatial Discrimination Learning Task, a radial Task that dissociates between spatial and response strategies (in Stage 2) after participants reached criteria (in Stage 1). Success on Stage 2 requires that participants have encoded the spatial relationship between the target object and environmental landmarks, that is, the spatial strategy. While older adults required more trials, all participants reached criterion. fMRI results showed that, as a group, young adults had significant activity in the hippocampus as opposed to older adults who instead had significant activity in the caudate nucleus. Importantly, individual differences showed that the older participants who used a spatial strategy to solve the Task had significant activity in the hippocampus. These findings suggest that the aging process involves a shift from using the hippocampus toward the caudate nucleus during Navigation but that activity in the hippocampus is sustained in a subset of healthy older adults engaged in spatial strategies.
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caudate nucleus dependent response strategies in a virtual Navigation Task are associated with lower basal cortisol and impaired episodic memory
Neurobiology of Learning and Memory, 2011Co-Authors: Veronique D Bohbot, Harrison Banner, Melini Gupta, Louisa DahmaniAbstract:The present research examined the relationship between endogenous glucocorticoids, Navigational strategies in a virtual Navigation Task, and performance on standard neuropsychological assessments of memory. Healthy young adult participants (N = 66, mean age: 21.7) were tested on the 4 on 8 virtual maze (4/8 VM) and standard neuropsychological tests such as the Rey-Osterrieth Complex Figure (RO) and the Rey Auditory Verbal Learning Task (RAVLT), which measure episodic memory. The 4/8 VM differentiates between Navigational strategies, where participants either use a hippocampal-dependent spatial strategy by building relationships between landmarks, or a caudate nucleus-dependent stimulus–response strategy by automatizing a pattern of open and closed arms to learn the location of objects within the maze. Degree of stress was assessed by administering the Perceived Stress Scale (PSS) questionnaire. Cortisol samples were taken on two consecutive days upon waking, 30 min after waking, at 11 am, 4 pm, and 9 pm. There was a significant difference in basal levels of cortisol between spatial and response learners. Interestingly, response learners had significantly lower cortisol levels throughout the day. The two groups did not differ in terms of perceived stress as measured with the PSS questionnaire. Moreover, there was no significant correlation between PSS scores and salivary cortisol levels, indicating that the higher cortisol levels in the spatial group were not associated with greater perceived stress. In addition, participants who spontaneously used a spatial strategy performed significantly better on the RAVLT and RO. These data indicate that the cortisol levels in the spatial group may be optimal in terms of episodic memory performance whereas the cortisol levels in the response group may be associated with poorer memory. These results are suggestive of an inverted U-shaped curve describing the effects of basal levels of circulating cortisol on memory in young adults.
L.j. Buxbaum - One of the best experts on this subject based on the ideXlab platform.
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Assessment of spatial attention and neglect with a virtual wheelchair Navigation Task
Journal of clinical and experimental neuropsychology, 2008Co-Authors: L.j. Buxbaum, D. Mastrogiovanni, M.s. Read, E. Rosenberg-pitonyak, Albert Rizzo, Mary Ann Palermo, H.b. CoslettAbstract:A total of 9 participants with right-hemisphere stroke performed a new virtual reality (VR) wheelchair Navigation test of lateralized spatial attention and neglect. The test consists of a virtual path along which participants navigate (or are navigated) as they name virtual objects encountered. There are 4 VR conditions, obtained by crossing the factors array complexity and driver. Participants performed the VR Task, a real-life wheelchair Navigation Task, and a battery of attention and neglect tests. The VR test showed sensitivity to both array complexity and driver, exhibited strong correlations with the wheelchair Navigation test, and detected lateralized attention deficits in mild patients. The VR Task thus shows promise as a sensitive, efficient measure of real-life Navigation.
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Assessment of Spatial Neglect with a Virtual Wheelchair Navigation Task
2006 International Workshop on Virtual Rehabilitation, 2006Co-Authors: L.j. Buxbaum, M. Palermo, D. Mastrogiovanni, M.s. Read, E. Rosenberg-pitonyak, Albert Rizzo, H.b. CoslettAbstract:We report data from 9 participants with right hemisphere stroke on a new virtual reality (VR) wheelchair Navigation test designed to assess lateralized spatial attention and neglect. The test consists of a virtual winding path along which participants must navigate (or be navigated by an experimenter) as they name objects encountered along the way. There are 4 VR Task conditions, obtained by crossing the factors array complexity (simple, complex) and driver (participant, experimenter). Participants performed the VR Task, a real-life wheelchair Navigation Task, and a battery of tests assessing arousal, visual attention under secondary Task demands, and neglect. The VR test showed sensitivity to both array complexity and driver, with best performance occurring in the experimenter-navigated, simple array condition. The VR test also showed high correlations with the wheelchair Navigation test, and these correlations were in many instances higher than those between traditional clinical neglect tests and the wheelchair Navigation Task. Moreover, the VR test detected lateralized attention deficits in participants whose performance was within the normal range on other neglect tests. We conclude that the VR Task is sensitive to factors likely to affect the severity of neglect in the daily environment, and shows promise as an efficient, easily administered measure of real-life wheelchair Navigation
Venkata Sreekanth Arikatla - One of the best experts on this subject based on the ideXlab platform.
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development and face validation of a virtual camera Navigation Task trainer
Surgical Endoscopy and Other Interventional Techniques, 2019Co-Authors: Venkata Sreekanth Arikatla, Sam Horvath, Lora A. Cavuoto, Steve Schwaitzberg, Andinet EnquobahrieAbstract:Background The fundamentals of laparoscopic surgery (FLS) trainer box, which is now established as a standard for evaluating minimally invasive surgical skills, consists of five Tasks: peg transfer, pattern cutting, ligation, intra- and extracorporeal suturing. Virtual simulators of these Tasks have been developed and validated as part of the Virtual Basic Laparoscopic Skill Trainer (VBLaST) (Arikatla et al. in Int J Med Robot Comput Assist Surg 10:344–355, 2014; Zhang et al. in Surg Endosc 27(10):3603–3615, 2013; Sankaranarayanan et al. in J Laparoendosc Adv Surg Tech 20(2):153–157, 2010; Qi et al. J Biomed Inform 75:48–62, 2017). The virtual Task trainers have many advantages including automatic real-time objective scoring, reduced costs, and eliminating human proctors. In this paper, we extend VBLaST by adding two camera Navigation system Tasks: (a) pattern matching and (b) path tracing.
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Development and face validation of a virtual camera Navigation Task trainer
Surgical endoscopy, 2018Co-Authors: Venkata Sreekanth Arikatla, Sam Horvath, Lora A. Cavuoto, Steve Schwaitzberg, Andinet EnquobahrieAbstract:The fundamentals of laparoscopic surgery (FLS) trainer box, which is now established as a standard for evaluating minimally invasive surgical skills, consists of five Tasks: peg transfer, pattern cutting, ligation, intra- and extracorporeal suturing. Virtual simulators of these Tasks have been developed and validated as part of the Virtual Basic Laparoscopic Skill Trainer (VBLaST) (Arikatla et al. in Int J Med Robot Comput Assist Surg 10:344-355, 2014; Zhang et al. in Surg Endosc 27(10):3603-3615, 2013; Sankaranarayanan et al. in J Laparoendosc Adv Surg Tech 20(2):153-157, 2010; Qi et al. J Biomed Inform 75:48-62, 2017). The virtual Task trainers have many advantages including automatic real-time objective scoring, reduced costs, and eliminating human proctors. In this paper, we extend VBLaST by adding two camera Navigation system Tasks: (a) pattern matching and (b) path tracing. A comprehensive camera Navigation simulator with two virtual Tasks, simplified and cheaper hardware interface (compared to the prior version of VBLaST), graphical user interface, and automated metrics has been designed and developed. Face validity of the system is tested with medical students and residents from the University at Buffalo's medical school. The subjects rated the simulator highly in all aspects including its usefulness in training to center the target and to teach sizing skills. The quality and usefulness of the force feedback scored the lowest at 2.62.
