Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 8 de 8
Filter
Add more filters










Database
Language
Publication year range
1.
iScience ; 27(6): 109871, 2024 Jun 21.
Article in English | MEDLINE | ID: mdl-38784005

ABSTRACT

For dexterous control of the hand, humans integrate sensory information and prior knowledge regarding their bodies and the world. We studied the role of touch in hand motor control by challenging a fundamental prior assumption-that self-motion of inanimate objects is unlikely upon contact. In a reaching task, participants slid their fingertips across a robotic interface, with their hand hidden from sight. Unbeknownst to the participants, the robotic interface remained static, followed hand movement, or moved in opposition to it. We considered two hypotheses. Either participants were able to account for surface motion or, if the stationarity assumption held, they would integrate the biased tactile cues and proprioception. Motor errors consistent with the latter hypothesis were observed. The role of visual feedback, tactile sensitivity, and friction was also investigated. Our study carries profound implications for human-machine collaboration in a world where objects may no longer conform to the stationarity assumption.

2.
Front Comput Neurosci ; 17: 1108311, 2023.
Article in English | MEDLINE | ID: mdl-36936193

ABSTRACT

Our previous articles demonstrated how to analyze psychophysical data from a group of participants using generalized linear mixed models (GLMM) and two-level methods. The aim of this article is to revisit hierarchical models in a Bayesian framework. Bayesian models have been previously discussed for the analysis of psychometric functions although this approach is still seldom applied. The main advantage of using Bayesian models is that if the prior is informative, the uncertainty of the parameters is reduced through the combination of prior knowledge and the experimental data. Here, we evaluate uncertainties between and within participants through posterior distributions. To demonstrate the Bayesian approach, we re-analyzed data from two of our previous studies on the tactile discrimination of speed. We considered different methods to include a priori knowledge in the prior distribution, not only from the literature but also from previous experiments. A special type of Bayesian model, the power prior distribution, allowed us to modulate the weight of the prior, constructed from a first set of data, and use it to fit a second one. Bayesian models estimated the probability distributions of the parameters of interest that convey information about the effects of the experimental variables, their uncertainty, and the reliability of individual participants. We implemented these models using the software Just Another Gibbs Sampler (JAGS) that we interfaced with R with the package rjags. The Bayesian hierarchical model will provide a promising and powerful method for the analysis of psychometric functions in psychophysical experiments.

3.
IEEE Trans Haptics ; 15(4): 693-704, 2022.
Article in English | MEDLINE | ID: mdl-36149999

ABSTRACT

Multiple cues contribute to the discrimination of slip motion speed by touch. In our previous article, we demonstrated that masking vibrations at various frequencies impaired the discrimination of speed. In this article, we extended the previous results to evaluate this phenomenon on a smooth glass surface, and for different values of contact force and duration of the masking stimulus. Speed discrimination was significantly impaired by masking vibrations at high but not at low contact force. Furthermore, a short pulse of masking vibrations at motion onset produced a similar effect as the long masking stimulus, delivered throughout slip motion duration. This last result suggests that mechanical events at motion onset provide important cues to the discrimination of speed.


Subject(s)
Motion Perception , Touch Perception , Humans , Touch , Vibration , Motion
4.
Dimens Crit Care Nurs ; 41(2): 76-82, 2022.
Article in English | MEDLINE | ID: mdl-35099153

ABSTRACT

BACKGROUND AND RELEVANCE: Early recognition of delirium mobilizes nurses to intervene in a timely manner to minimize cognitive, physical, and mental health burdens. The life-altering challenges of unrecognized delirium in intensive care unit (ICU) patients motivated a group of Massachusetts ICU nurse leaders to form a collaborative and improve delirium screening accuracy in 4 area hospitals. LOCAL PROBLEM: Baseline audits confirmed a lack of delirium screening accuracy across multiple institutions. The purpose of this article is to describe how our collaborative was developed and to outline our delirium accuracy assessment program. METHODS: In March of 2015, 2 graduates from the Clinical Scene Investigator Academy contacted members within the Boston cohort to form a regional collaborative to improve patient outcomes. The purpose of our project was to improve our delirium assessment accuracy to greater than 80% in patients across our ICUs. Using a successful project, we scaled this work based on the needs of each institution. A preaudit-postaudit design was used to evaluate the effectiveness of our programs. RESULTS: Data showed an improved overall accuracy assessment of 88.3% (P < .01), whereas the patients with an altered Richmond Agitation Sedation Scale markedly improved to 87.7% (P < .01). CONCLUSIONS: Every ICU in the United States is working on improving reportable quality metrics, but all too often, this work is being done in silos. When critical care nurses have the knowledge, skills, and time to work together, they can begin to transform health care.


Subject(s)
Delirium , Nurses , Critical Care , Delirium/diagnosis , Hospitals , Humans , Intensive Care Units
5.
J Neurophysiol ; 126(4): 1375-1390, 2021 Oct 01.
Article in English | MEDLINE | ID: mdl-34495782

ABSTRACT

Besides providing information on elementary properties of objects, like texture, roughness, and softness, the sense of touch is also important in building a representation of object movement and the movement of our hands. Neural and behavioral studies shed light on the mechanisms and limits of our sense of touch in the perception of texture and motion, and of its role in the control of movement of our hands. The interplay between the geometrical and mechanical properties of the touched objects, such as shape and texture, the movement of the hand exploring the object, and the motion felt by touch, will be discussed in this article. Interestingly, the interaction between motion and textures can generate perceptual illusions in touch. For example, the orientation and the spacing of the texture elements on a static surface induces the illusion of surface motion when we move our hand on it or can elicit the perception of a curved trajectory during sliding, straight hand movements. In this work we present a multiperspective view that encompasses both the perceptual and the motor aspects, as well as the response of peripheral and central nerve structures, to analyze and better understand the complex mechanisms underpinning the tactile representation of texture and motion. Such a better understanding of the spatiotemporal features of the tactile stimulus can reveal novel transdisciplinary applications in neuroscience and haptics.


Subject(s)
Illusions/physiology , Motion Perception/physiology , Somatosensory Cortex/physiology , Touch Perception/physiology , Touch/physiology , Humans
6.
Eur Radiol Exp ; 5(1): 41, 2021 09 17.
Article in English | MEDLINE | ID: mdl-34532768

ABSTRACT

BACKGROUND: Transperineal laser ablation (TPLA) of the prostate is a novel, mini-invasive option for men with lower urinary tract symptoms (LUTS) due to benign prostate hyperplasia (BPH). Our aim was to assess the impact of ultrasound-guided TPLA regarding urodynamic improvement and sexual function, monitoring clinical data, postprocedural complications and imaging findings at 3-T multiparametric magnetic resonance imaging. METHODS: Forty-four patients aged ≥ 50 affected with moderate to severe LUTS (International Prostate Symptoms score ≥ 12) due to benign prostatic obstruction and refractoriness, intolerance or poor compliance to medical therapies underwent US-guided TPLA between May 2018 and February 2020. Clinical measurements included PSA, uroflowmetry, sexual function assessment (using the International Index of Erectile Function and Male Sexual Health Questionnaire-Ejaculatory Dysfunction short form) and quality of life questionnaire. Adverse events were evaluated using the Clavien-Dindo scale. Volume changes were measured by MRI and automatic segmentation software during 1-year follow-up. Registration: NCT04044573 - May 5th, 2018, https://www.clinicaltrials.gov RESULTS: MRI assessed the changes over time with a 53% mean reduction of adenoma volume and 71% of the ablated area, associated with clinical and functional improvement and resolution of LUTS in all cases. Five of 44 patients (11.3%) had urinary blockage due to clots and required re-catheterisation for 2 weeks. The overall adverse event rate was 7%. CONCLUSION: US-guided TPLA performed as a safe, manageable and effective treatment for LUTS. It could be considered an alternative effective mini-invasive procedure to standard treatments for BPH in the outpatient setting.


Subject(s)
Laser Therapy , Prostatic Hyperplasia , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Prostatic Hyperplasia/diagnostic imaging , Prostatic Hyperplasia/surgery , Quality of Life , Ultrasonography, Interventional
7.
Prostate Cancer Prostatic Dis ; 23(2): 356-363, 2020 06.
Article in English | MEDLINE | ID: mdl-31827239

ABSTRACT

PURPOSE: To investigate the effectiveness and safety of SoracteLite™-transperineal percutaneous laser ablation (TPLA) in the treatment of patients with symptomatic benign prostatic hyperplasia (BPH) at 6 and 12 months follow-up. METHODS: Patients with urinary symptoms secondary to BPH underwent TPLA under local anesthesia in four centers. Under US guidance, up to four 21G applicators were inserted in the prostatic tissue. Each treatment was performed with diode laser operating at 1064 nm changing the illumination time according to prostate size. The primary end-points of this study were change in IPSS, PVR, Qmax, QoL, and prostatic volume at 6 an 12 months from SoracteLiteTM TPLA treatment. Secondary end-point was the assessment of complications. RESULTS: Analysis was performed on data 160 patients (mean age 69.8 ± 9.6 years) with at least 6 months follow and of 83 patients (mean age 67.9 ± 8.7 years) with at least 12 months follow-up. At 6 months, IPSS improved from 22.5 ± 5.1 to 7.7 ± 3.3 (P < 0.001), PVR from 89.5 ± 84.6 to 27.2 ± 44.5 ml (P < 0.001), Qmax from 8.0 ± 3.8 to 14.3 ± 3.9 ml/s (P < 0.001), QoL from 4.5 ± 1.1 to 1.8 ± 1.0 (P < 0.001), volume from 75.0 ± 32.4 to 60.3 ± 24.5 ml (P < 0.001). At 12 months, IPSS improved from 22.5 ± 4.5 to 7.0 ± 2.9 (P < 0.001), PVR from 71.7 ± 93.9 to 17.8 ± 51.0 ml (P < 0.001), Qmax from 8.6 ± 5.2 to 15.0 ± 4.0 ml/s (P < 0.001), QoL from 4.2 ± 0.6 to 1.6 ± 0.9 (P < 0.001), volume from 87.9 ± 31.6 to 58.8 ± 22.9 ml (P < 0.001). 7/160 (4.3%) grade I and 1/160 (0.6%) grade III complication occurred. CONCLUSIONS: SoracteLite™ TPLA allows significant improvement of IPSS, Qol, Qmax, PVR, and reduction of prostatic volume at 6 and 12 months.


Subject(s)
Laser Therapy/methods , Lower Urinary Tract Symptoms/prevention & control , Perineum/surgery , Prostatic Hyperplasia/surgery , Quality of Life , Aged , Feasibility Studies , Follow-Up Studies , Humans , Male , Prostatic Hyperplasia/pathology , Retrospective Studies , Time Factors , Treatment Outcome
8.
Physiol Behav ; 207: 86-89, 2019 08 01.
Article in English | MEDLINE | ID: mdl-31022409

ABSTRACT

The existence of yawning across a diverse array of species has led many researchers to postulate its neurological significance. One hypothesis, which has garnered recent support, posits that yawns function to cool the brain by flushing hyperthermic blood away from the skull while simultaneously introducing a cooler arterial supply. The current study tested this hypothesis by examining how manipulations aimed at modifying carotid artery temperature, which in turn directly alters cranial temperature, influences contagious yawning in humans. Participants held either a warm (46 °C), cold (4 °C) or room temperature (22 °C) pack firmly to their neck, just over their carotid arteries, for a period of five minutes prior to watching a contagious yawning stimulus. Thermographic imaging verified that these manipulations produced predicted changes in temperature at the superomedial orbital area, a region previously used as a noninvasive measure of brain temperature (i.e., the brain temperature tunnel). As predicted by past research, both the urge to yawn and overall yawn frequency significantly diminished in the cooling condition (p < .05). Less than half (48.5%) of the participants in the cooling condition reported the urge to yawn, while this urge was expressed by the vast majority of participants in the warming condition (84.8%). Moreover, there was a threefold difference in the mean number of yawns per participant between the cooling and warming conditions (0.364 compared to 1.121). These findings are consistent with previous research indicating that yawns function as a compensatory brain cooling mechanism.


Subject(s)
Body Temperature/physiology , Imitative Behavior , Neck/physiology , Yawning/physiology , Adaptation, Psychological , Adolescent , Adult , Brain/physiology , Carotid Arteries/physiology , Female , Humans , Male , Social Behavior , Thermography , Young Adult
SELECTION OF CITATIONS
SEARCH DETAIL
...