Does Temporal Expectation Driven by Rhythmic Cues Differ From That Driven by Symbolic Cues Across the Millisecond and Second Range?

Perception ◽  
2019 ◽  
Vol 48 (6) ◽  
pp. 515-529 ◽  
Author(s):  
Yanna Ren ◽  
Zhihan Xu ◽  
Fengxia Wu ◽  
Yoshimichi Ejima ◽  
Jiajia Yang ◽  
...  

Temporal expectation relies on different predictive information, such as regular rhythms and symbolic cues, to direct attention to a future moment in time to optimize behaviour. However, whether differences exist between temporal expectations driven by regular rhythms and symbolic cues has not been clearly established. In this study, 20 participants performed two temporal expectation tasks in which a rhythmic cue or a symbolic cue indicated (70% expected) that the target would appear after an interval of 500 ms (short), 1,500 ms (medium), or 2,500 ms (long). We found larger cueing effects for the rhythmic cued task than for the symbolic cued task during the short interval, indicating that rhythmic cues were more effective in improving performance. Furthermore, no significant difference was found during the longer interval, reflect that the behavioural differences between the two forms of temporal expectations were likely to diminish as the time interval increased. Thus, we speculate that the temporal expectation driven by rhythmic cues differs from that driven by symbolic cues only in the limited time range; however, the mechanisms underlying the two forms of temporal expectations trend to become more similar over increasing temporal scales.

2021 ◽  
pp. 088506662110197
Author(s):  
Moosa Azadian ◽  
Suyee Win ◽  
Amir Abdipour ◽  
Carolyn Krystal Kim ◽  
H. Bryant Nguyen

Background: Fluid therapy plays a major role in the management of critically ill patients. Yet assessment of intravascular volume in these patients is challenging. Different invasive and non-invasive methods have been used with variable results. The passive leg raise (PLR) maneuver has been recommended by international guidelines as a means to determine appropriate fluid resuscitation. We performed this systematic review and meta-analysis to determine if using this method of volume assessment has an impact on mortality outcome in patients with septic shock. Methods: This study is a systematic review and meta-analysis. We searched available data in the MEDLINE, CINAHL, EMBASE, and CENTRAL databases from inception until October 2020 for prospective, randomized, controlled trials that compared PLR-guided fluid resuscitation to standard care in adult patients with septic shock. Our primary outcome was mortality at the longest duration of follow-up. Results: We screened 1,425 article titles and abstracts. Of the 23 full-text articles reviewed, 5 studies with 462 patients met our eligibility criteria. Odds ratios (ORs) and associated 95% confidence intervals (CIs) for mortality at the longest reported time interval were calculated for each study. Using random effects modeling, the pooled OR (95% CI) for mortality with a PLR-guided resuscitation strategy was 0.82 (0.52 -1.30). The included studies were not blinded and they ranged from having low to high risk of bias using the Cochrane Risk of Bias Tool. Conclusion: Our analysis showed there was no statistically significant difference in mortality among septic shock patients treated with PLR-guided resuscitation vs. those with standard care.


2019 ◽  
Vol 6 ◽  
pp. 205566831982580 ◽  
Author(s):  
Ruslinda Ruslee ◽  
Jennifer Miller ◽  
Henrik Gollee

Introduction: Functional electrical stimulation is a common technique used in the rehabilitation of individuals with a spinal cord injury to produce functional movement of paralysed muscles. However, it is often associated with rapid muscle fatigue which limits its applications. Methods: The objective of this study is to investigate the effects on the onset of fatigue of different multi-electrode patterns of stimulation via multiple pairs of electrodes using doublet pulses: Synchronous stimulation is compared to asynchronous stimulation patterns which are activated sequentially (AsynS) or randomly (AsynR), mimicking voluntary muscle activation by targeting different motor units. We investigated these three different approaches by applying stimulation to the gastrocnemius muscle repeatedly for 10 min (300 ms stimulation followed by 700 ms of no-stimulation) with 40 Hz effective frequency for all protocols and doublet pulses with an inter-pulse-interval of 6 ms. Eleven able-bodied volunteers (28 ± 3 years old) participated in this study. Ultrasound videos were recorded during stimulation to allow evaluation of changes in muscle morphology. The main fatigue indicators we focused on were the normalised fatigue index, fatigue time interval and pre-post twitch–tetanus ratio. Results: The results demonstrate that asynchronous stimulation with doublet pulses gives a higher normalised fatigue index (0.80 ± 0.08 and 0.87 ± 0.08) for AsynS and AsynR, respectively, than synchronous stimulation (0.62 ± 0.06). Furthermore, a longer fatigue time interval for AsynS (302.2 ± 230.9 s) and AsynR (384.4 ± 279.0 s) compared to synchronous stimulation (68.0 ± 30.5 s) indicates that fatigue occurs later during asynchronous stimulation; however, this was only found to be statistically significant for one of two methods used to calculate the group mean. Although no significant difference was found in pre-post twitch–tetanus ratio, there was a trend towards these effects. Conclusion: In this study, we proposed an asynchronous stimulation pattern for the application of functional electrical stimulation and investigated its suitability for reducing muscle fatigue compared to previous methods. The results show that asynchronous multi-electrode stimulation patterns with doublet pulses may improve fatigue resistance in functional electrical stimulation applications in some conditions.


2015 ◽  
Vol 44 (5) ◽  
pp. 262-267 ◽  
Author(s):  
José Vitor Quinelli Mazaro ◽  
Luiz Miguel Minani ◽  
Adriana Cristina Zavanelli ◽  
Caroline Cantieri de Mello ◽  
Cleidiel Aparecido Araújo Lemos

AbstractIntroductionTemporary restorative materials are widely used, however, little is know about their color stability.Objectiveto evaluate the color stability of the following temporary restorative materials: acrylic and bis-acrylic resins after immersion in pigmenting solutions for different periods of storage.Material and methodFour materials were tested (Dêncor/Clássico, Protemp 4/3M ESPE; Structur 2 SC/Voco; Luxatemp AM Plus/DMG) and 30 test specimens (15 mm in diameter and 2 mm thick) per material were fabricated. They were divided according to the storage medium (artificial saliva, saliva + cola type soda, and saliva + coffee) and storage time intervals (2, 5, 7 and 15 days). Color measurements were made before and after immersions, with use of a spectrophotometer, by means of the CIE L*a*b* system. The data were analyzed by the analysis of variance and the Tukey Test, at a level of significance of 5%.ResultAcrylic resin presented greater color stability in comparison with bis-acrylic resins (p<0.001). When bis-acrylic resins were compared no significant difference was observed between the resins Structur and Luxatemp (p=0.767). As regards solutions tested, coffee showed the highest color change values (p<0.001), and the longer the storage time interval, the greater was the color change in all the temporary restorative materials analyzed (p<0.001).ConclusionAcrylic resin presented greater color stability in comparison with bis-acrylic resins (p<0.001). Coffee caused the greatest color change, and immersion time was determinant in color stability of the temporary materials analyzed.


1975 ◽  
Vol 40 (2) ◽  
pp. 535-538 ◽  
Author(s):  
Philip H. Marshall ◽  
Susan L. Wyatt ◽  
Shirley A. Moore ◽  
Stephen E. Sigman

An investigation was conducted to ascertain the influence of the duration of the time interval between successive repetitions of a discrete motor movement in a short-term motor memory paradigm. With one repetition a long interval increased error relative to a short interval. The opposite was true for seven repetitions; a long interval improved accuracy. The results were discussed in terms of the “trace shrinkage” hypothesis and compared with those from similar studies using verbal responses.


2018 ◽  
Vol 22 (04) ◽  
pp. 382-386
Author(s):  
Maheer Masood ◽  
Trevor Hackman

Introduction Intraoperative parathyroid hormone (ioPTH) testing is a widely accepted standard for assessing the parathyroid gland function. A decline of preoperative parathyroid hormone (PTH) levels by more than 50% is one accepted measure of parathyroid surgery adequacy. However, there may be a variation between preoperative PTH levels obtained at a clinic visit and pre-excisional ioPTH. Objective Our study explores the differences between preoperative PTH and pre-excisional ioPTH levels, and the potential impact this difference has on determining the adequacy of parathyroid surgery. Methods A retrospective study that consisted of 33 patients that had undergone parathyroid resection between September 2009 and March 2016 at a tertiary academic center was performed. Each subject's preoperative PTH levels were obtained from clinic visits and pre-excisional ioPTH levels were recorded along with the time interval between the measurements. Results There was a significant difference between the mean preoperative PTH and the pre-excisional ioPTH levels of 147 pg/mL (95% confidence interval [CI] 11.43 to 284.47; p = 0.0396). The exclusion of four outliers revealed a further significant difference with a mean of 35.09 pg/mL (95% CI 20.27 to 49.92; p < 0.0001). The average time interval between blood draws was 48 days + 32 days. A weak correlation between the change in PTH values and the time interval between preoperative and pre-excision blood draws was noted (r2 = 0.15). Conclusion Our study reveals a significant difference between the preoperative PTH levels obtained at clinic visits and the pre-excisional intraoperative PTH levels. We recommend routine pre-excisional intraoperative PTH levels, despite evidence of elevated preoperative PTH levels, in order to more accurately assess the adequacy of surgical resection.


2003 ◽  
Vol 131 (5-6) ◽  
pp. 226-231
Author(s):  
Ivana Golubicic ◽  
Jelena Bokun ◽  
Marina Nikitovic ◽  
Jasmina Mladenovic ◽  
Milan Saric ◽  
...  

PURPOSE The aim of this study was: 1. to evaluate treatment results of combined therapy (surgery, postoperative craniospinal radiotherapy with or without chemotherapy) and 2. to assess factors affecting prognosis (extend of tumor removal, involvement of the brain stem, extent of disease postoperative meningitis, shunt placement, age, sex and time interval from surgery to start of postoperative radiotherapy). PATIENTS AND METHODS During the period 1986-1996, 78 patients with medulloblastoma, aged 1-22 years (median 8.6 years), were treated with combined modality therapy and 72 of them were evaluable for the study end-points. Entry criteria were histologically proven diagnosis, age under 22 years, and no history of previous malignant disease. The main characteristics of the group are shown in Table 1. Twenty-nine patients (37.2%) have total, 8 (10.3%) near total and 41 (52.5%) partial removal. Seventy-two of 78 patients were treated with curative intent and received postoperative craniospinal irradiation. Radiotherapy started 13-285 days after surgery (median 36 days). Only 13 patients started radiotherapy after 60 days following surgery. Adjuvant chemotherapy was applied in 63 (80.7%) patients. The majority of them (46 73%) received chemotherapy with CCNU and Vincristine. The survival rates were calculated with the Kaplan-Meier method and the differences in survival were analyzed using the Wilcoxon test and log-rank test. RESULTS The follow-up period ranged from 1-12 years (median 3 years). Five-year overall survival (OS) was 51% and disease-free survival (DFS) 47% (Graph 1). During follow-up 32 relapses occurred. Patients having no brain stem infiltration had significantly better survival (p=0.0023) (Graph 2). Patients with positive myelographic findings had significantly poorer survival compared to dose with negative myelographic findings (p=0.0116). Significantly poorer survival was found in patients with meningitis developing in the postoperative period, with no patient living longer than two years (p=0.0134) (Graph 3). By analysis of OS and DFS in relation to presence of the malignant cells in liquor, statistically significant difference, i. e. positive CSF cytology was not obtained, which was of statistical importance for survival (p=0.8207). Neither shunt placement nor shunt type showed any impact on survival (p=0.5307 and 0.7119, respectively). Children younger than three years had significantly poorer survival compared to those older than 16 years (p=0.0473). Although there was a better survival rate in females than in males this was not statistically significant (p=0.2386).The analysis results of treatment showed that significantly better survival occurred in patients in whom total or subtotal tumor removal was possible (p=0.0022) (Graph 4). Patients who started radiotherapy within two months after surgery have better survival, but again this was not statistically significant, probably due to the small number of patients receiving delayed radiotherapy (p=0.2231)(Graph5). CONCLUSION Based on this factors standard and high risk group could be defined. Combined chemotherapy should to be investigated particularly for high risk subgroup. Future research should be done to define new therapeutic modalities (gene therapy, compounds active in tumor antiangiogenesis etc).


2021 ◽  
Author(s):  
Guangqian Shang ◽  
Shuai Xiang ◽  
Jianjun Guo ◽  
Feng Ji ◽  
Shuai Yang ◽  
...  

Abstract Background: This study explored the optimal time interval between staged bilateral total knee arthroplasty (BTKA) to minimise early complications of the second TKA and maximise long-term function of the first and second knees.Methods: We retrospectively reviewed 266 patients who underwent staged BTKA between 2010 and 2015. Groups 1–4 had time intervals between BTKAs of 1–6, 6–12, 12–18, and 18–24 months, respectively. Demographics, postoperative complications within 90 days of the second TKA, Knee Society Score (KSS), and Western Ontario and McMaster Universities Arthritis Index (WOMAC) score were compared among the groups.Results: In total, 54, 96, 75, and 41 patients were assigned to groups 1–4, respectively. Although group 1 had the highest overall complication rate (11.11%), there was no significant difference in the complication rate among the four groups. Also, no significant differences were found among the four groups in functional and patient-reported outcomes, in either the first or second knee at 5 years postoperatively, including KSS-knee, KSS-function, WOMAC-pain, WOMAC-stiffness, and WOMAC-physical function. The interval between BTKA did not influence complications or the function of the second knee. The TKA type (posterior-stabilised vs. medial-pivot) and age did not correlate significantly with any scores.Conclusions: There was no group difference in early complications of the second TKA, and postoperative function was equivalent between the two knees and did not vary by the interval between surgeries. Our results can help surgeons discuss the timing of the second TKA with patients, which should be based on their own preferences. If patients cannot tolerate severe symptoms in the contralateral knee after the first TKA, the second TKA should be performed as early as possible.


2006 ◽  
Vol 21 (8) ◽  
pp. 551-562 ◽  
Author(s):  
Thomas A. Pagonis ◽  
Nikiforos V. Angelopoulos ◽  
George N. Koukoulis ◽  
Christos S. Hadjichristodoulou

AbstractObjectiveThe objective of our study was to evaluate the psychological consequences of real-world AAS use in athletes abusing such agents, in comparison with a placebo and control group of comparable athletes, while correlating the severity of abuse with the side effects observed. The hypothesis tested by the study was that the use of AAS induces a wide range of psychological side effects whose impact and emergence is dependent upon the severity of the abuse.DesignThe study includes a substantial group of AAS abusing athletes and two more groups demographically similar to the first, one composed of athletes not using any substance and a placebo group. All athletes were stratified according to the severity of AAS abuse. Psychometric instruments were applied to all athletes in specific time intervals, dependent to the AAS abusers' regimens, providing us with a final psychological profile that was to be compared to the pre-study profile. All results were comparable (within and between groups) for statistically significant differences and correlated to the severity of the abuse. Homogeneity of all groups was safeguarded by random doping controls, monitoring of drug levels and analysis of all self obtained drugs by method of liquid chromatography/mass spectrometry. All athletes were provided with a common exercise and dietary regime, so common training and nutritional conditions were achieved.MethodsWe studied a cohort of 320 body-building, amateur and recreational athletes, of whom 160 were active users of AAS (group C), 80 users administering placebo drugs (group B) and 80 not abusing any substance (Group A). Group C athletes were stratified according to AAS abuse parameters, thus providing us with three subgroups of “light, medium and heavy abuse”. Athletes of groups A and B were included in a “no abuse” subgroup. The psychometric instruments used were the Symptoms Check List-90 (SCL-90) and the Hostility and Direction of Hostility Questionnaire (HDHQ). The psychometric evaluations took place within a time interval of 13 months. Statistical analysis was performed by using the Mann–Whitney/Wilcoxon two-sample non-parametric test (Kruskal–Wallis test for two groups) for data that were not normally distributed and Linear regression analysis was used to ascertain the correlation between severity of use and escalation of side effects.ResultsThe study showed a statistically significant increase in all psychometric subscales recorded in group C, and no statistically significant difference in group C and A. There was a significant increase in the scorings of group C for all subscales of SCL-90 and HDHQ. Correlation of abuse severity and side effects showed that there was a statistical significant increase in Δ values of all SCL-90 and HDHQ subscales that escalated from light abuse to medium and heavy abuse/consumption patterns.ConclusionsThe results of the study suggest that the wide range of psychiatric side effects induced by the use of AAS is correlated to the severity of abuse and the force of these side effects intensifies as the abuse escalates.


Circulation ◽  
2014 ◽  
Vol 130 (suppl_2) ◽  
Author(s):  
Elisa Carturan ◽  
Stefania Rizzo ◽  
Gaetano Thiene ◽  
Cristina Basso

Introduction: Myocarditis is diagnosed on endomyocardial biopsy (EMB) by histological, immune-histochemical and molecular techniques to detect viral genomes. The role of EMB for the diagnosis and its contribution to patient management has been addressed by a Consensus document of American and European Cardiovascular Pathology Societies. Hypothesis: Different methods of tissue fixation and the number of myocardial samples could impact on viral genome yield on EMB. Methods: Consecutive EMBs referred at our Institution for histology/ immunohistochemistry evaluation in the time interval 1996-2012 were enrolled. Molecular investigation by RT-PCR and PCR technique was performed in all EMBs with inflammatory cardiomyopathy diagnosis at histology and immunohistochemistry. Results: A total of 467 EMBs have been diagnosed as myocarditis: 79 in pediatric (1 month to 18 years; 47M/ 32F) and 388 adult (19 to 75 years; 256M/132 F) patients (pts.). Viral etiology was identified in 28 (36%) pediatric and 101 (26%) adult pts, and the most prevalent type of viruses were enterovirus (8/28, 36%; 26/101, 24%). In a more recent subgroup of 137 EMBs (virus positive 30/137, 22%) seasonality, type of fixation and number of EMB samples were assessed. The seasonal distribution of myocarditis was higher in winter than in other seasons (33% vs. autumn 28%, spring 20% and summer 19%) without any significant difference in terms of virus positive EMBs. The number of EMB samples per pt. was ≤3 (either formalin or RNAlater) in 94/137 (69%) and >3 in 43/137 (31%), with a lower prevalence of virus positive in the former (17/94, 18% vs. 13/43, 30%). Eighty-one EMB samples were frozen while 56 were paraffin embedded, with a higher prevalence of viral genome in the former (26/81, 32% vs. 4/56, 7%; p=0.001). Conclusions: The diagnosis of myocarditis on EMB samples requires standardized protocols including molecular techniques. Viral genomes are identifiable in more than one third of pediatric and one fourth of adult cases. Methodological factors like the type of tissue fixation and the number of samples could impact on viral genome detection on EMB.


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