Search

This work involves augmenting the Δ (5 4) flavor symmetry model by incorporating two Standard Model Higgs particles into the Inverse Seesaw mechanism. The mass matrices are discussed numerically in the framework of Δ (5 4) flavor for Majorana neutrinos. We introduced Vector-like fermions and Weyl fermions, which are gauge singlets in the Standard Model and produces Majorana mass terms. We restrict the undesirable terms in our Lagrangian by using additional symmetry. Due to these additional terms, the mass matrices deviate from the tribimaximal neutrino mixing pattern, resulting in the production of a nonzero reactor angle θ 1 3 . We found that the atmospheric oscillation parameter ( θ 2 3 ) occupies the upper octant under the normal hierarchy situation. We also study the CP violation ( δ CP ), Jarlskog invariant parameter (J) and Neutrinoless double-beta decay parameter ( m e e ) in the parameter space of the normal hierarchy model to see whether they concur with the most recent neutrino observations. [ABSTRACT FROM AUTHOR]

We study a neutrino mass model with A 4 discrete flavor symmetry using a type-I seesaw mechanism. The inclusion of extra flavons in our model leads to deviations from the exact tribimaximal mixing pattern resulting in a nonzero θ 1 3 consistent with the recent experimental results and a sum rule for light neutrino masses is also obtained. In this framework, a connection is established among the neutrino mixing angles-reactor mixing angle ( θ 1 3 ), solar mixing angle ( θ 1 2 ), and atmospheric mixing angle ( θ 2 3 ). This model also allows us a prediction of Dirac CP-phase and Jarlskog parameter (J). The octant of the atmospheric mixing angle θ 2 3 occupies the lower octant. Our model prefers Normal Hierarchy (NH) than Inverted Hierarchy (IH). We use the parameter space of our model of neutrino masses to study the neutrinoless double beta decay parameter m β β . [ABSTRACT FROM AUTHOR]

BACKGROUND: Middle ear effusion (MEE) and tympanic membrane perforation (TMP) are difficult to distinguish using existing immittance techniques, necessitating the use of a separate test battery. Wideband absorbance (WBA) tympanometry is a new enhanced technique, and studies have shown a reliable WBA pattern to identify middle ear disorders. Thus, the study was performed to determine the WBA across the frequencies in ears with MEE, TMP, and compared with normal hearing individuals. METHODS: A total of 109 ears with TMP and 122 ears with MEE in the age range of 22-50 years were compared with 150 normal hearing ears. Otoscopic examination, middle ear fluid monitor, pure tone audiometry, and immittance measurements were performed to categorize the subject ears into groups. The absorbance levels at peak and ambient pressure across one-third octave frequencies in each group were statistically evaluated at α=0.05. RESULTS: Wideband absorbance for the normal ear group was lowest at low (<800 Hz) and high frequencies (>3000 Hz) and highest at midfrequency regions (800-3000 Hz). The MEE group had significantly lower WBA at all frequencies, and TMP group showed reduced WBA at low and mid-frequencies (<2500 Hz). Wideband absorbance at peak pressure was slightly higher than ambient pressure in all the groups. Receiver operating characteristic analysis demonstrated a high diagnostic value in the mid-frequency region for both the TMP and MEE groups. CONCLUSION: Wideband absorbance provides high reliability in discriminating between MEE and TMP and has a unique WBA pattern. Thus, WBA can be a useful diagnostic tool for the identification of middle ear disorders. [ABSTRACT FROM AUTHOR]

In the context of language descriptions, the terms oral and verbal praxis refer to volitional movements for performing oral gestures and movements for speech. These movements involve programming articulators and rapid sequences of muscle firings that are required for speech sound productions. A growing body of research has highlighted the links between oral motor kinematics and language production skills in both typically developing (TD) children and children with developmental language disorders, including Specific Language Impairment (SLI). Yet, there have been limited attempts to assess the link between non-linguistic and linguistic development. In the present study, we investigated oral and verbal praxis behaviors in children with SLI. Fifteen children with SLI formed a clinical group and 15 children with typical development who were matched to the clinical group for chronological age, gender, and socio-economic status formed the TD group. We assessed participants in both groups for their language abilities with age-appropriate standardized language tests. To investigate oral and verbal praxis behaviors, we administered the Assessment Protocol for Oral Motor, Oral Praxis and Verbal Praxis Skills to the two groups. We used the non-parametric Mann–Whitney U test to compare the two groups with respect to oral and verbal praxis measures; and we found a significant difference between isolated and sequential movements in the oral praxis section in two age subgroups of these groups (p ≤.05). Spearman's correlations revealed a strong correlation between core language scores and sequential movements in the younger children with SLI and in TD children. These results showed co-morbidity between SLI and poor oral motor skills, suggesting that SLI is not just a language disorder, but a group of co-morbid conditions that include oral motor and verbal praxis difficulties. [ABSTRACT FROM AUTHOR]

Introduction: Studies have demonstrated that mothers exaggerate linguistic, segmental and supra-segmental properties of Child-Directed Speech. However, these studies have majorly focused on acoustic characteristics of pitch and its related measures. There has been relatively little research on speech rhythm. Though many studies report slower articulation rate relative to Adult-Directed Speech, still there is no conclusive evidence across different languages. Aims: This study aims to examine articulation rate and rhythm in Kannada speaking mothers, a Dravidian language which is less explored. Methods and Material: Twenty-five dyads of mothers and their children were recruited from the local community through random sampling for the study. The mean age of these children was 2.08 years (SD = 0.61, range= 1.89). The mean age of mothers was 30.96 years (SD= 3.44, range= 13). Articulation rate was calculated by dividing the number of syllables per second by the total duration of fluent speech in each two-minute sample. Speech rhythm was measured using an automatized approach, i.e., Envelope Modulation Spectra (EMS). Results: Results demonstrated that mothers spoke slower to their children when compared to speaking with the adult supporting the universality nature of Child-Directed Speech. Conclusions: However, results showed no conclusive evidence for the analysis of speech rhythm and hence gives a future direction to explore on the use of EMS in the normal population is mandated. [ABSTRACT FROM AUTHOR]

Specific language impairment (SLI) is a developmental disorder when a child has difficulty in producing or understanding spoken language for no apparent reason. The study attempts to carry out an in-depth review of electrphysiological findings in individuals with SLI. Review of literature was carried out to review and critical analyse the electrophysiological findings in individuals with SLI. The results of the review showed contradicting results in this population. Some studies have reported a statistically significant difference in morphology, latency and amplitude of auditory evoked potentials (AEPs) between the children with SLI and the control group. This suggests that children with SLI may have auditory processing problems at the level of brainstem, sub-cortical and cortical areas. While few other studies showed no abnormalities in auditory processing in children with SLI, with intact waveform morphology, latency and amplitude of AEPs. AEPs were observed to be more variable lacking uniformity because of the heterogeneous nature of SLI. However, further studies need to be conducted to evaluate the auditory processing abilities using auditory evoked potentials in children with SLI. [ABSTRACT FROM AUTHOR]

Aim: To study auditory stream perception in sensorineural hearing loss using sinusoidally amplitude modulated signals (SAM). Material and methods: There were 30 participants with normal hearing and 30 participants with SNHL who participated in the study. Two experiments were conducted. In Experiment I, an AB sequence of SAM stimuli was presented having a standard or reference modulation frequency in the A stimuli and a comparison or target modulation frequency in the B stimuli. In Experiment II, only a B stimuli sequence was presented. Both a low carrier frequency of 1 kHz and a high carrier frequency of 4 kHz were used in the experiment. A lower standard modulation frequency of 16 Hz and a higher standard modulation frequency of 256 Hz were considered. The comparison modulation frequencies ranged from 1 octave above to 4 octaves above the standard modulation frequencies. The objective listening task was to pick the irregularity in the rhythmic sequence when different levels of time delays were introduced, and this delay was used as a measure of stream perception. Results: There was a significant difference between the normal hearing group and the SNHL group in their ability to detect irregularities when higher standard modulation frequencies were used, irrespective of the carrier frequencies. The SNHL group identified the irregularities better than the normal hearing group, indicating they had poorer stream perception. Conclusions: Poorer stream perception with sinusoidal amplitude modulated tonal stimuli in the SNHL group can be attributed to poorer frequency resolution in the SNHL group. [ABSTRACT FROM AUTHOR]

Background: Middle ear pressure plays a vital role in the transmission of sound to the inner ear. However, limited research data exists to understand the effect of abnormal middle ear pressure on wideband absorbance (WBA) tympanometry. The purpose of the study was to evaluate WBA at peak pressure and ambient pressure in adults with abnormal positive and negative middle ear pressure and compare them with normal adult ears having normal middle ear pressure. Material and methods: Three groups of adults -- normal middle ear pressure group (56 ears), negative middle ear pressure group (30 ears), and positive middle ear pressure group (15 ears) -- in the age range 22 to 50 years were considered. WBA was measured at peak and ambient pressures across the frequencies from 250 to 8000 Hz. Results: WBA at peak pressure was observed to be higher than at ambient pressure in all the groups, with the difference seen mostly at low and mid-frequencies up to 2000 Hz. The negative middle ear pressure group showed the most considerable difference in mean WBA, seen between 600 Hz and 1000 Hz, followed by the positive middle ear pressure group, with a negligible difference for the normal middle ear pressure group. Conclusions: The study highlighted the importance of measuring WBA at peak pressure and ambient pressure. The results suggest that the comparison of WBA at peak and ambient pressures, especially from lower to mid-frequencies up to 2000 Hz, would help in differentiating abnormal negative/positive pressure from normal middle ear pressure and also between ears having negative and positive pressure. [ABSTRACT FROM AUTHOR]

Background and Aim: Auditory stream segregation is a phenomenon that splits sounds into different streams. The temporal cues that contribute for stream segregation have been previously studied in normal hearing people. In people with sensorineural hearing loss (SNHL), the cues for temporal envelope coding is not usually affected, while the temporal fine structure cues are affected. These two temporal cues depend on the amplitude modulation frequency. The present study aimed to evaluate the effect of sinusoidal amplitude modulated (SAM) broadband noises on stream segregation in individuals with SNHL. Methods: Thirty normal hearing subjects and 30 subjects with mild to moderate bilateral SNHL participated in the study. Two experiments were performed; in the first experiment, the AB sequence of broadband SAM stimuli was presented, while in the second experiment, only B sequence was presented. A low (16 Hz) and a high (256 kHz) standard modulation frequency were used in these experiments. The subjects were asked to find the irregularities in the rhythmic sequence. Results: Both the study groups could identify the irregularities similarly in both the experiments. The minimum cumulative delay was slightly higher in the SNHL group. Conclusion: It is suggested that the temporal cues provided by the broadband SAM noises for low and high standard modulation frequencies were not used for stream segregation by either normal hearing subjects or those with SNHL. [ABSTRACT FROM AUTHOR]

Objective: The study aimed at examining the usefulness of inter-frequency amplitude ratio (IFAR) of ocular vestibular evoked myogenic potential (oVEMP) in identifying Meniere's disease (MD) and differentiating it from benign paroxysmal positional vertigo (BPPV). Design: A case-control design was used with a double blind approach. Phase 1 included 70 healthy individuals and 36 individuals each with MD and BPPV and Phase 2 included 20 individuals each with MD and BPPV. The age range of the participants in both phases was 15-50 years. All participants underwent oVEMP testing using 500 and 1000 Hz tone bursts and IFAR was obtained. Results: The results in phase 1 revealed significantly higher IFARs in Meniere's disease than BPPV and healthy individuals (p < 0.001). An optimum criterion point of IFAR ≥1.11 for diagnosing MD was found which yielded 80% sensitivity and 98% specificity. The results in phase 2 demonstrated 85% correct identification of MD and 95% correct rejection of BPPV as non-MD. Conclusions: IFAR of oVEMP appears highly sensitive and specific parameter for identifying MD and a clinically valid tool for differentiating MD from BPPV. [ABSTRACT FROM AUTHOR]

Introduction The studies on hearing aid benefit in individuals with auditory neuropathy spectrum disorder (ANSD) shows limited benefit. Low cut modified amplification is found to be effective in few individuals with ANSD. With advancement in technology, receiver in the canal (RIC) hearing aids have proven to be more effective than traditional behind the ear (BTE) hearing aids. Objective Thus, the present study attempts to determine the effectiveness of low cut modified amplification using RIC and BTE. Method Twenty participants with ANSD were fitted with BTE and RIC using traditional and low cut modified amplification. We divided them into good and poor performers based on unaided speech identification scores (SIS). We then compared aided SIS and aided benefit across conditions in good and poor performers with ANSD across both conditions using BTE and RIC. Results The results of the study showed that the aided performance improved with low cut modified amplification in both BTE and RIC hearing aids. The improvement noticed with low-cut modified fitting with RIC was significant in more than BTE, especially in good performers with ANSD. Conclusion The improved clarity and naturalness of sound with RIC may have led to better aided scores and better acceptance of the hearing aid. Thus, low-cut modified amplification, preferably with RIC, needs to be attempted in fitting individuals with ANSD, especially in those with good unaided SIS in quiet. [ABSTRACT FROM AUTHOR]

Background: Conventionally, it is believed that high-frequency auditory information is important for speech understanding. This is only partly true, as recent studies have demonstrated the importance of low-frequency information. This research was taken up to develop, standardize, and validate auditory low-frequency word lists in Hindi, an Indian language. Material and methods: The first phase of the study involved collection of bisyllabic words followed by verification by a native linguist. Words were then short-listed based on familiarity ratings given by 10 adult native speakers; those words were recorded and the best recorded words selected through subjective and objective analysis. Then, using Fast Fourier Transform and k-means clustering, words with more energy below 1.5 kHz were isolated. Finally, equally difficult 10 word lists were generated by obtaining psychometric function curves. Finally, lists were administered on 40 adult normal hearing participants at 0, 10, 20, and 30 dB sensation level (SL). The word list was also standardized on 100 Hindi speakers at 40 dB SL. Results: Results showed a similar trend of increase in speech identification scores with increase in SL across all lists except list 4. During the final phase, developed lists were validated on 10 simulated low-frequency cochlear hearing loss participants. Hearing loss was simulated using Matlab and National Institute for Occupational Safety and Health (NIOSH) software. Results of validation revealed that auditory low-frequency word lists were sensitive enough to tap the speech understanding difficulty in the simulated condition. Conclusions: The developed word lists can be used clinically to assess communication ability in individuals with rising hearing loss. The word lists also have the potential to assess the performance after amplification provided to individuals with rising hearing loss. [ABSTRACT FROM AUTHOR]