Top-down auditory plasticity: Acceptable noise level predicts and reflects the effect of perceptual learning in experience-induced plasticity

Objective: In the auditory system, tinnitus and superior speech perception in noise are examples of negative and positive plasticity that can result from sensory neural hearing loss and life experiences dealing with more complex stimuli and learning, respectively. Positive plasticity occurs as a result of learned skills and sensory stimuli; plasticity involves specific neural pathways and can be observed in auditory ascending or descending pathways.Materials & Methods: In this study, we document a form of plasticity in top-down auditory pathways through the measurement of acceptable noise level in 60 adults (27 females and 33 males) with normal hearing. Individuals were assigned to one of two groups: those with and without occupational experience of speech perception in noise.Result: The results showed that the test group had statistically significant lower acceptable noise level and significantly higher background noise level scores compared with the control group.Conclusion: Using acceptable noise level, we attributed differences in individuals’ abilities to tolerate varying amounts of background noise and speech perception in noise function to the auditory efferent system. We therefore concluded that working in crowded locations due to job nature can influence differences in speech perception in noise function

Test-retest & Inter rater Reliability of Persian version of Pediatric Balance Scale in Children with Spastic Cerebral Palsy

Objective: Children affected with spastic cerebral palsy have a lot of difficulties in terms of movement and balance. Balance is one of the necessary variables of movement, which facilitates functional skills. The aim of this inter rater & test-retest reliability study relating to Pediatric Balance Scale (PBS) for children withspastic cerebral palsy, was based on mild to moderate motor impairment or loss of movement.Materials and Methods: In this analytical-descriptive research performed in the rehabilitation centers, south of Tehran, Iran in 2016, psychometric method was used. For investigating the inter-rater reliability, two examiners performed the scale simultaneously with 50 children with spastic cerebral palsy. Moreover, to investigate the test-retest reliability, the scale was implemented by one examiner, in two different sessions, among 50 children with spastic cerebral palsy. There was a two-week period between the first and the second session.Results : The inter rater reliability (ICC = 0/99) as well as the  test-retest reliability (1/100) was quite highConclusionPBS is appropriate for measuring functional balance in children with spastic cerebral palsy with mild to moderate motor impairment

The effect of the timing of umbilical cord clamping on hemoglobin levels, neonatal outcomes and developmental status in infants at 4 months old

Objective:Delayed umbilical cord clamping (DCC) increases blood transfer to newborns. Hence we investigated the effect of the timing of DCC on hemoglobin levels, neonatal outcomes and developmental status in infants at four months old.Materials & Methods:This clinical trial examined infants born to 400 pregnant women immediately upon birth and at the age of four months. The newborns were randomly assigned to either the intervention group with a 90-120-second delay in umbilical cord clamping or the control group with a clamping delay of below 60 seconds, and blood samples were taken from their umbilical cords. The Ages and Stages Questionnaire was used to evaluate the infants’ developmental status.Results:Umbilical cord hemoglobin was found to be significantly higher in the intervention group compared to in the controls (P=0/024). No significant differences were observed between the two groups in terms of neonatal complications except neonatal jaundice was significantly more common in the intervention group (P=0/025), although the need for phototherapy was not different between the groups. Overall, no significant differences were observed between the two groups in terms of developmental status at four months old; however, the infants had better problem-solving skills in the delayed umbilical cord clamping group (P=0/015).Conclusion:The results obtained show that, despite elevating hemoglobin, delayed umbilical cord clamping but has no effects on infant development except in terms of problem-solving skills. Further studies are recommended on the effects of delayed umbilical cord clamping on infant development

The effect of core stability training with and without whole body vibration in chronic low back pain patients

The subjective of this study was to explore and compare the effects of Whole Body Vibration (WBV) and conventional spinal stabilization exercises on persons with non-specific chronic low back pain (CLBP). Thirty patients with non-specific chronic low back pain randomly received 6 sessions of spinal stabilization therapy with and without whole body vibration over 2 weeks. The severity of pain, functional disability,  abdominal and lumbar multifidus muscle endurance were assessed prior to, midway and after two week  WBV or spinal stabilization intervention program sequentially by using VAS score, Oswestry disability index and stabilizer pressure biofeedback unit. Repeated measure ANOVA was used for data analysis. A p-value <0.05 was considered as statistically significant. Findings show that multifidus muscle endurance and general functionality  increase significantly over time in both groups (P <0/05). Both groups didn't show any statistically significant change in perception of pain, supine and prone time after the treatment period (P>0/05) .Neither of the two exercise interventions wasn't superior in producing more significant results except for multifidus and transverse abdominus muscles endurance where the vibration group showed significant improvement over the non-vibration group. Findings revealed that a slight difference existed in favor of the vibration training group, but not sufficient enough to conclude that it is more effective than core muscle exercises alone

Microhardness of Calcium-enriched Mixture Cement and Covering Glass Ionomers after Different Time Periods of Application

Introduction: Various studies have recommended using calcium-enriched mixture (CEM) cement in different endodontic treatments, including vital pulp therapy. However, possible reciprocal effects of the covering glass ionomer cement (GIC) on their mechanical properties have not been yet investigated in detail. The current research aimed to experimentally evaluate the surface microhardness of CEM cement and the covering GICs after different application/testing times. Materials and Methods: Using stainless steel moulds (8×4×4 mm), CEM cement samples were prepared (n=120) and randomly divided into 12 experimental groups (n=10). CEM cement with thickness of 4 mm was inserted into the moulds, and the remaining spaces were filled with self-cured or light-cured resin-modified GICs at three-time intervals; immediate, in 15 min and after 24 h. Then, the samples were incubated for one and seven days. Using a Vickers microhardness tester, the microhardness of CEM and GICs was measured. The data were analyzed using two-way ANOVA and Tukey’s test, and the significance level was set at 5% (P<0.05). Results: The reciprocal effects of the type/time of application of GICs on the surface microhardness of CEM cement or GICs were statistically significant (P<0.001). The surface microhardness of CEM cement and both covering GICs significantly increased over time and in seven-day samples was significantly higher than in one-day samples (P<0.05). Conclusions: Low surface microhardness of CEM/GICs in short-term (24 h) seems transient; and appears to be compensated over a longer period (i.e. 7-day). Therefore, using GICs adjacent to CEM cement in single-visit restorative treatments may be advocate

Application of Outlier Robust Nonlinear Mixed Effect Estimation in Examining the Effect of Phenylephrine in Rat Corpus Cavernosum

Abstract Ignoring two main characteristics of the concentration-response data, correlation between observations and presence of outliers, may lead to misleading results. Therefore, the special method should be considered. The present study was designed to apply the outlier robust nonlinear mixed estimation for effects of phenylephrine on rat corpus cavernosum strips. In this study, eight different doses of phenylephrine in eight experimental groups were used. Each group consisted of eight rats. The concentration-response curves to phenylephrine (0.1µM to 300µM) were obtained by the cumulative addition of phenylephrine to the chamber. Because of the existence of an outlier to achieve robust estimations, M-estimation method and Huber function as a dispersion function were used. Cumulative administration of phenylephrine (0.1µM -300µM) caused concentration-dependent contractions in strips of rat corpus cavernosum (-Log EC 50 was 5 ± 0.31, 95% CI= 5.92 to 4.21). The contraction of corpus cavernosum started in the concentration of 0.3 μM and then gradually increased in a dose-dependent manner till it reached a plateau in 100 μM. To consider the clustering feature of concentration-response data, the 4pl regression with a random term has been used. To estimate parameters, because of existence of an outlier in dataset, the robust procedure has been applied. The contraction of corpus cavernosum started in the concentration of 0.3 μM and then gradually increased in a dose-dependent manner till it reached a plateau in 100 μM

Combined Transcranial Direct Current Stimulation with Occupational Therapy Improves Activities of Daily Living in Traumatic Brain Injuries: A Pilot Randomized Clinical Trial

Introduction: Traumatic brain injury (TBI) is one of the leading causes of long-term disability worldwide. Occupational therapy interventions in these patients are mainly focused on improving patients’ ability to perform daily occupations. Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation technique whose potential for motor and cognitive recovery of patients with TBI has been investigated; however, its effect on functional outcomes following TBI is unknown. This study aims to determine the effectiveness of tDCS combined with routine occupational therapy on the activities of daily living in patients with TBI. Materials and Methods: This was a single-blind, randomized clinical trial. A total of 24 patients with TBI were recruited using the convenience sampling method and were randomly assigned to the experimental (n=12) and control groups (n=12). Both groups underwent routine occupational therapy for 10 sessions (3 days per week), and the experimental group received tDCS (20 min) in addition to routine occupational therapy. Activities of daily living were assessed using the functional independence measure (FIM) at the baseline and the day after the end of the intervention. Results: After a 10-session intervention, both groups experienced significant improvements in the cognitive subscale and the FIM total score (P<0.001). Additionally, the findings showed that these improvements were significantly higher in the experimental group (P<0.001). Conclusion: According to the findings, although routine occupational therapy can effectively improve the ability of patients with TBI to perform daily living activities, adding tDCS as a complementary intervention can accelerate recovery in these patients

Effect of background music on auditory-verbal memory performance

Background and Aim: Music exists in all cultures; many scientists are seeking to understand how music effects cognitive development such as comprehension, memory, and reading skills. More recently, a considerable number of neuroscience studies on music have been developed. This study aimed to investigate the effects of null and positive background music in comparison with silence on auditory-verbal memory performance.Methods: Forty young adults (male and female) with normal hearing, aged between 18 and 26, participated in this comparative-analysis study. An auditory and speech evaluation was conducted in order to investigate the effects of background music on working memory. Subsequently, the Rey auditory-verbal learning test was performed for three conditions: silence, positive, and null music.Results: The mean score of the Rey auditory-verbal learning test in silence condition was higher than the positive music condition (p=0.003) and the null music condition (p=0.01). The tests results did not reveal any gender differences.Conclusion: It seems that the presence of competitive music (positive and null music) and the orientation of auditory attention have negative effects on the performance of verbal working memory. It is possibly owing to the intervention of music with verbal information processing in the brain

Comparison of Electrical Activity of Core Stability Muscles of Trunk and Knee Muscles in People With and Without Patellofemoral Pain Syndrome during Stair-Stepping

Introduction: Patellofemoral Pain Syndrome (PFPS) is known as one of the most frequent knee diseases in athletic and non-athletic people and the most frequent cause of anterior knee pain. Despite the high prevalence of PFPS, its predisposing factors are not known. Among the potential factors, neuromuscular control disorders of lumbopelvic hip complex or core have been recently focused because the stability of this complex is vital for movements of limbs and the instability of core redounds to the instability of whole movement chain. The knee is the most prevalent joint influenced by core disorders; it seems that knee is a victim of core stability disorders. Materials and Methods: This is a descriptive-analytic case-control study. Thirty-two subjects including 17 patients with PFPS (10 female, 7 male) and 15 healthy subjects (8 female, 7 male) participated in this study. Electrical activity of vastus medialis obliqus, adductor longus, gluteus maximus, external oblique abdominus (EOA), internal oblique abdominus (IOA) and transverse abdominus (TA) and multifidus was recorded during the stair-stepping activity. All statistical analyses were performed with the SPSS version 20.0 software. Results: The results showed there was a significant difference (P=0.026 for EOA, P=0.03 for IOA and TA) between the offset time of electrical activity of core abdominal muscles in patients with PFPS and healthy subjects during stair-stepping. However, there were no significant differences in other parameters. Conclusion: The end of electrical activity of abdominal muscles in patients with PFPS during stair-stepping was longer than healthy subjects. However, managing patients with PFPS is challenging because there is no consensus regarding its predisposing factors and treatment. Therefore, more accurate recognition of this syndrome is needed to develop an appropriate treatment.Keywords: Core Stability Muscles; Electromyography; Knee Muscles; Patellofemoral Pain Syndrom

Temporal acuity and speech recognition score in noise in patients with multiple sclerosis

Background and Aim: Multiple sclerosis (MS) is one of the central nervous system diseases can be associated with a variety of symptoms such as hearing disorders. The main consequence of hearing loss is poor speech perception, and temporal acuity has important role in speech perception. We evaluated the speech perception in silent and in the presence of noise and temporal acuity in patients with multiple sclerosis.Methods: Eighteen adults with multiple sclerosis with the mean age of 37.28 years and 18 age- and sex- matched controls with the mean age of 38.00 years participated in this study. Temporal acuity and speech perception were evaluated by random gap detection test (GDT) and word recognition score (WRS) in three different signal to noise ratios.Results: Statistical analysis of test results revealed significant differences between the two groups (p<0.05). Analysis of gap detection test (in 4 sensation levels) and word recognition score in both groups showed significant differences (p<0.001).Conclusion: According to this survey, the ability of patients with multiple sclerosis to process temporal features of stimulus was impaired. It seems that, this impairment is important factor to decrease word recognition score and speech perception