126 research outputs found

    Gender differences in nonlinear motor performance following concussion

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    Purpose: To quantify differences in nonlinear aspects of performance on a seated visual-motor tracking task between clinically asymptomatic males and females with and without a self-reported mild traumatic brain injury (mTBI) history. Methods: Seventy-three individuals with a self-reported concussion history (age: 21.40 ± 2.25 years) and 75 without (age: 21.50 ± 2.00 years) completed the visual-motor tracking task. Participants pressed an index finger against a force sensor, tracing a line across a computer screen (visual-motor tracking). The produced signal\u27s root-mean-square error (RMSE), sample entropy (SampEn, a measure of regularity), and average power (AvP) between 0 and 12 Hz were calculated. Results: Males with a history of 0 or 1 concussion had greater RMSE (worse performance) than females with 0 (p \u3c 0.0001) and 1 concussion (p = 0.052). Additionally, females with 2+ concussions exhibited lower SampEn than females with no history (p = 0.001) or a history of 1 concussion (p = 0.026). Finally, females with 2+ concussions had lower 8–12 Hz AvP than males with 2+ concussions (p = 0.031). Few differences were observed in the male participants. Conclusion: Females with a self-reported history of multiple concussions exhibited lower SampEn in the visual-motor tracking-task force output structure as compared to those with no reported history of concussion and their male counterparts. Lower SampEn and lower power between 8 and 12 Hz indicated persistent impairment in visual processing and feed-forward or predictive motor control systems

    Design and Partial Implementation of Convertoplane

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    Import 02/11/2016Tato diplomová práce se zabývá návrhem bezpilotního prostředku v konstrukčním řešení typu konvertoplán. První část diplomové práce se zabývá zběžnému seznámení s bezpilotními prostředky, typy konstrukčního řešení a možnostmi jejich využití. Dále následuje připomenutí výsledků bakalářské práce, na kterou tato diplomová práce navazuje. Pak práce přechází na návrh bezpilotního prostředku v konstrukci konvertoplánu, výběrem druhu pohonu a následnou realizací, popisem postupu sestavení prototypu bezpilotního prostředku založeného na konstrukci konvertoplánu. Závěr práce je zaměřen na informace týkající se tzv. ,,oživení“ prototypu a zhodnocení dosažených výsledků.This diploma thesis describes design of Unmanned Aerial Vehicle (UAV) in construction type convertiplane. First part of thesis presents high level introduction to UAV, types of design solutions and posibilities of their utilization. It is followed by the summary of the results from the bachelor thesis that was used as a base for this thesis. Furthermore, the thesis deals with the draft of UAV in construction type convertiplane, choice of drive and subsequent implementation, description of the building process of UAV prototype based on construction type convertiplane. The final part of thesis is focused on information related to the so called “bringing prototype to life” and evaluating the results of thesis.342 - Institut dopravyvelmi dobř

    How Autism Spectrum Disorder Affects Action Preparation in Children

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    Visual Feedback is Not Important for Bimanual Human Interval Timing

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    The clock variance of intervals produced by one finger is reduced when that finger taps along with another finger (termed the bimanual advantage). The multiple-timekeeper model proposes a coupling of internal clocks, leading to reduced clock variance for bimanual timing. Alternatively, reduced variance for bimanual timing could result from additional sensory feedback from two fingers as opposed to one. We aimed to test the role of visual feedback in reducing temporal variability. Participants tapped unimanually and bimanually (with no table contact) in three conditions: full vision, blindfolded, and with additional visual feedback provided via a mirror reflecting the right hand. We predicted that temporal variability would be reduced for tapping with vision versus no vision, and when the left hand was represented by a mirror but did not actually tap. Additional, redundant visual information did not reduce temporal variability for any condition, suggesting that visual feedback is not crucial for bimanual advantage. These findings support the role of sensory feedback (namely, tactile, auditory, and proprioceptive) in reducing timekeeper variability during bimanual timing and argue against a strictly multiple-timekeeper model

    The Role of Multiple Internal Timekeepers and Sources of Feedback on Interval Timing

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    The aim of this experiment was to document the role of multiple internal clock mechanisms and external sources of temporal feedback on reducing timing variability when two fingers tap instead of one (a phenomenon known as the bimanual advantage). Previous research documents a reduction in timed interval variability when two effectors time instead of one. In addition, interval variability decreases with multiple sources of feedback. To date, however, no research has explored the separate roles of feedback and internal timing on the bimanual advantage. We evaluated the bimanual advantage in a task that does not utilise an internal clock (circle drawing). Participants performed both unimanual and bimanual timing while tapping or drawing circles. Both tasks were performed with and without tactile feedback at the timing goal. We document reduced bimanual timing variability only for tasks that utilise internal clock-like timing (tapping). We also document reduced timing variability for timing with greater sensory feedback (tactile vs no-tactile feedback tapping). We conclude that internal clock mechanisms are necessary for bimanual advantage to occur, but that multiple sources of feedback can also serve to improve internal timing, which ties together current theories of bimanual advantage

    The Role of Multiple Internal Timekeepers and Sources of Feedback on Interval Timing

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    The aim of this experiment was to document the role of multiple internal clock mechanisms and external sources of temporal feedback on reducing timing variability when two fingers tap instead of one (a phenomenon known as the bimanual advantage). Previous research documents a reduction in timed interval variability when two effectors time instead of one. In addition, interval variability decreases with multiple sources of feedback. To date, however, no research has explored the separate roles of feedback and internal timing on the bimanual advantage. We evaluated the bimanual advantage in a task that does not utilise an internal clock (circle drawing). Participants performed both unimanual and bimanual timing while tapping or drawing circles. Both tasks were performed with and without tactile feedback at the timing goal. We document reduced bimanual timing variability only for tasks that utilise internal clock-like timing (tapping). We also document reduced timing variability for timing with greater sensory feedback (tactile vs no-tactile feedback tapping). We conclude that internal clock mechanisms are necessary for bimanual advantage to occur, but that multiple sources of feedback can also serve to improve internal timing, which ties together current theories of bimanual advantage

    Conversational Alignment: A Study of Neural Coherence and Speech Entrainment

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    Conversational alignment refers to the tendency for communication partners to adjust their verbal and non-verbal behaviors to become more like one another during the course of human interaction. This alignment phenomenon has been observed in neural patterns, specifically in the prefrontal areas of the brain (Holper et al., 2013; Cui et al., 2012; Dommer et al., 2012; Holper et al., 2012; Funane et al., 2011; Jiang et al., 2012); verbal behaviors such acoustic speech features (e.g., Borrie & Liss, 2014; Borrie et al., 2015; Lubold & Pon-Barry, 2014), phonological features (e.g., Babel, 2012; Pardo, 2006), lexical selection (e.g., Brennan & Clark, 1996; Garrod & Anderson, 1989), syntactic structure (e.g., Branigan, Pickering, & Cleland, 2000; Reitter, Moore, & Keller, 2006); and motor behaviors including body posture, facial expressions and breathing rate (e.g., Furuyama, Hayashi, & Mishima, 2005; Louwerse, Dale, Bard, & Jeuniaux, 2012; Richardson, March, & Schmit, 2005; Shockley, Santana, & Fowler, 2003; McFarland, 2001). While conversational alignment in itself, is a largely physical phenomenon, it has been linked to significant functional value, both in the cognitive and social domains. Cognitively, conversational alignment facilitates spoken message comprehension, enabling listeners to share mental models (Garrod & Pickering, 2004) and generate temporal predictions about upcoming aspects of speech. From a social perspective, behavioral alignment has been linked with establishing turn-taking behaviors, and with increased feelings of rapport, empathy, and intimacy between conversational pairs (e.g., Lee et al. 2010; Nind, & Macrae, 2009; Smith, 2008; Bailenson & Yee, 2005; Chartrand & Barg, 1999; Miles, Putman & Street, 1984; Street & Giles, 1982). Benus (2014), for example, observed that individuals who align their speech features are perceived as more socially attractive and likeable, and have interactions that are more successful. These cognitive and social benefits, associated with conversational alignment, have been observed in both linguistic and neural data (e.g., Holper et al., 2012; 2013, Cui et al. 2012; Jiang et al., 2012; Egetemeir et al., 2011; Stephens et al. 2010). The purpose of the current study was to examine conversational alignment as a multi-level communication phenomenon, by examining the relationship between neural and speech behaviors. To assess neural alignment, we used Near-Infrared Spectroscopy (NIRS), a non-invasive neuroimaging technology that detects cortical increases and decreases in the concentration of oxygenated and deoxygenated hemoglobin at multiple measurement sites to determine the rate that oxygen is being released and absorbed (Ferrari & Quaresima, 2012). While still considered a relatively new neural imaging technique, NIRS has been well established as an efficacious and effective data collection approach, particularly appropriate for social interaction research (e.g., Holper et al., 2013; Jiang et al., 2012; Holper et al., 2012; Suda et al., 2010). We utilized hyperscanning, a technique that allows for the quantitation of two simultaneous signals, allowing us to document neural alignment between two individuals (Babiloni & Astolfi, 2012). Recent studies have revealed neural alignment between two persons in cooperative states, including alignment in the right superior frontal cortices and medial prefrontal regions (Cui et al., 2012; Dommer et al., 2012; Funane et al., 2011). This increased prefrontal interbrain alignment has also been observed in other social interactions, including joint attention tasks (Dommer et al., 2012), imitation tasks (Holper et al., 2012), competitive games (Cheng et al., 2015, Duan et al., 2013), teaching-learning interactions (Holper et al., 2013), face- to-face communication (Jiang et al., 2012), mother-child interactions (Hirata et al., 2014), and during cooperative singing tasks (Osaka et al., 2015). Interestingly, Jiang et al. (2012) showed that increased neural alignment only occurred between conversational participants when they were speaking face-to-face, but not when participants had their backs facing one another. The authors speculated that the multi-sensory information, for example motor behaviors such as gestures, was required for neural alignment to occur

    Training compliance control yields improvements in drawing as a function of beery scores

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    Many children have difficulty producing movements well enough to improve in sensori-motor learning. Previously, we developed a training method that supports active movement generation to allow improvement at a 3D tracing task requiring good compliance control. Here, we tested 7–8 year old children from several 2nd grade classrooms to determine whether 3D tracing performance could be predicted using the Beery VMI. We also examined whether 3D tracing training lead to improvements in drawing. Baseline testing included Beery, a drawing task on a tablet computer, and 3D tracing. We found that baseline performance in 3D tracing and drawing co-varied with the visual perception (VP) component of the Beery. Differences in 3D tracing between children scoring low versus high on the Beery VP replicated differences previously found between children with and without motor impairments, as did post-training performance that eliminated these differences. Drawing improved as a result of training in the 3D tracing task. The training method improved drawing and reduced differences predicted by Beery scores
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