The Impact of Age-Related Hearing Loss on Working Memory among Older Individuals: An Event-Related Potential Study.

Introduction: Age-related hearing loss (ARHL) may affect working memory (WM), which impacts problem-solving, decision-making, language comprehension, and learning. Limited research exists on how ARHL affects WM using N-back tasks, but studying this is crucial for understanding neural markers and associated cognitive processes. Our study explores the impact of ARHL on WM using behavioral and electrophysiological measures and how it correlates with speech-in-noise scores in older individuals with ARHL. Method: The study involved two groups, each with 20 participants aged 60-80. Group 1 had individuals with mild to moderate sensorineural hearing loss, while Group 2 had age- and education-matched controls with normal or near-normal hearing. Participants underwent audiological assessments and completed cognitive tests, including simple reaction time and N-back tests. During the performance of cognitive tasks, a simultaneous electroencephalography was recorded. Data analysis included behavioral and event-related potentials, source estimation, and functional connectivity analysis. Results: The study revealed significantly poor accuracy, longer reaction time, and smaller P300 amplitude among individuals with ARHL, even after controlling for general slowing. Individuals with ARHL experience compromised neural activity, particularly in the temporal and parietal regions, which are vital for cognition and WM. Furthermore, individuals with ARHL exhibited poor communication between the superior temporal gyrus and insulae regions among the brain regions mediating WM during the 1-back task. Also, the study found a strong correlation between hearing measures and WM outcomes. Conclusion: The study findings suggest that individuals with ARHL have impaired WM compared to those with normal hearing. This indicates a potential link between ARHL and cognitive decline, which could significantly affect daily life and quality of life. The widely used WM test with simultaneous EEG recording and source estimation analysis would further validate the usefulness of the study in assessing WM in this population.

Development and Validation of the Spatial Separation Sentence Test in Kannada.

Background and Objectives: : This study aimed to develop and validate a modified version of the Speech in Noise Sentence Test in Kannada, which would be appropriate for testing the speech comprehension ability of children aged 8-12 years. Subjects and Methods: : A total of 120 sentences were chosen from 200 familiar sentences and split into four lists. Continuous discourse was used as a competition or distractor. Using MATLAB, the target stimulus was presented at 0-degree azimuth while the distractor's location varied (+90° and -90° azimuth). The test was programmed to dynamically adjust the signal-to-noise ratio (SNR) based on participants' responses. After initial validation, a pilot study was conducted with 60 typically hearing children aged 8 to 12 years. Results: : The SNR50 scores significantly improved when the distractor and target sentences were spatially separated across all groups. Age had a significant influence on the spatial separation scores. The test-retest reliability was excellent. Conclusions: : The developed stimuli effectively measured spatial separation, and the normative and psychometric analyses demonstrated reliable outcomes.

Development, and validation of non-speech dichotic listening test.

Background: Classic dichotic listening tests using speech stimuli result in right ear advantage, due to the dominant crossed pathway for speech and language. It is presumed that similar crossed dominance could exist for non-speech stimuli too. Hence, this is an attempt to develop and validate the dichotic non-speech test using environmental stimuli and explore the effect of focused attention on this test. Materials and method: Three lists of dichotic stimuli were created using these sounds with fifteen tokens in each list. Four professionals and non-professionals validated these materials. Normative estimation was obtained by administering the newly developed test on 70 adults and 70 children using a free-recall and forced-recall condition. Result: The results showed a significant difference between the left ear and right scores where the left ear score was better than the right, depicting left ear advantage (LEA) for free recall condition in both groups. In the forced recall condition, LEA was not seen; rather the mean score was significantly higher in the attended ear, irrespective of the stimuli presented to the right or left ear. The test-retest reliability in free recall was good in both the ears and moderate for forced right ear conditions. Conclusion: The novel test consistently showed LEA with good reliability and can be used to assess the hemispheric asymmetry in normal subjects and also in test batteries for the clinical population.

Cortical Reorganization Following Psychoeducational Counselling and Residual Inhibition Therapy (RIT) in Individuals with Tinnitus

Abstract Introduction Psychoeducational counselling and residual inhibition therapy (RIT) are traditional approaches used in many clinics to manage tinnitus. However, neurophysiological studies to evaluate posttreatment perceptual and functional cortical changes in humans are scarce. Objectives The present study aims to explore whether cortical auditory-evoked potentials (CAEPs; N1 and P3) reflect the effect of modified RIT and psychoeducational counselling, and whether there is a correlation between the behavioral and electrophysiological measures. Methods Ten participants with continuous and bothersome tinnitus underwent a session of psychoeducational counselling and modified RIT. Perceptual measures and CAEPs were recorded pre- and posttreatment. Further, the posttreatment measures were compared with age and gender-matched historical control groups. Results Subjectively, 80% of the participants reported a reduction in the loudness of their tinnitus. Objectively, there wasasignificant reductioninthe posttreatment amplitude of N1 and P3, with no alterations in latency. There was no correlation between the perceived difference in tinnitus loudness and the difference in P3 amplitude (at Pz). Conclusion The perceptual and functional (as evidenced by sensory, N1, and cognitive, P3 reduction) changes after a single session of RIT and psychoeducational counselling are suggestive of plastic changes at the cortical level. The current study serves as preliminary evidence that event-related potentials (ERPs) can be used to quantify the physiological changes that occur after the intervention for tinnitus.

Influence of Sedentary Behaviour Interventions on Vascular Functions and Cognitive Functions in Hypertensive Adults-A Scoping Review on Potential Mechanisms and Recommendations.

Since the workplace has become desk-based and leisure time has become dominated by digital relaxation modes, the world is moving at a pace where physical activity has become a time-bound routine. The negative effects of extended sitting are a global concern since the workforce is becoming more desk based. There is a dearth of reviews that may link the knowledge on the effects of sedentary behaviour on hypertension and its accompanying damage to the brain and blood vessels and provide a future scope for the investigations connected to the relationship between sedentary behaviour and hypertension. Methods: Based on the database search and extensive research we did, we found studies that concentrated on the adverse effects of sedentary behaviour in association with blood pressure, cognitive decline and brain damage on adults. Results: We extracted 12 articles out of 20,625. We identified the potential adverse effects of sedentary behaviour, methods to reduce sedentary behaviour and the positive changes on health due to the interventions introduced. Sedentary lifestyle has shown a decline in human health. However, the visible symptoms presented later in life makes it very important to know the areas of decline and look for ways to curb the decline or procrastinate it.

Cortical Reorganization Following Psychoeducational Counselling and Residual Inhibition Therapy (RIT) in Individuals with Tinnitus.

Introduction Psychoeducational counselling and residual inhibition therapy (RIT) are traditional approaches used in many clinics to manage tinnitus. However, neurophysiological studies to evaluate posttreatment perceptual and functional cortical changes in humans are scarce. Objectives The present study aims to explore whether cortical auditory-evoked potentials (CAEPs; N1 and P3) reflect the effect of modified RIT and psychoeducational counselling, and whether there is a correlation between the behavioral and electrophysiological measures. Methods Ten participants with continuous and bothersome tinnitus underwent a session of psychoeducational counselling and modified RIT. Perceptual measures and CAEPs were recorded pre- and posttreatment. Further, the posttreatment measures were compared with age and gender-matched historical control groups. Results Subjectively, 80% of the participants reported a reduction in the loudness of their tinnitus. Objectively, there was a significant reduction in the posttreatment amplitude of N1 and P3, with no alterations in latency. There was no correlation between the perceived difference in tinnitus loudness and the difference in P3 amplitude (at Pz). Conclusion The perceptual and functional (as evidenced by sensory, N1, and cognitive, P3 reduction) changes after a single session of RIT and psychoeducational counselling are suggestive of plastic changes at the cortical level. The current study serves as preliminary evidence that event-related potentials (ERPs) can be used to quantify the physiological changes that occur after the intervention for tinnitus.

Systematic review and meta-analysis on the effect of continuous subjective tinnitus on attention and habituation.

BACKGROUND: Attention and habituation are two domains known to play key roles in the perception and maintenance of tinnitus. The heterogeneous nature of tinnitus and the methodologies adopted by various studies make it difficult to generalize findings. The current review aims at assessing and synthesizing evidence on the possible roles of attention and habituation in continuous subjective tinnitus. METHODOLOGY: The literature search included five databases (PubMed, Scopus, Web of Sciences, CINAHL and ProQuest) that resulted in 1,293 articles, published by July 2019. Studies on attention and/or habituation in individuals with tinnitus using either behavioural or electrophysiological tests were included in the review after a quality assessment. RESULTS: Seventeen studies on attention in tinnitus were included in the narrative synthesis. Two meta-analyses were performed to assess the role of attention in tinnitus using a behavioural methodology (z = 4.06; p < 0.0001) and P300 amplitude (z = 2.70; p = 0.007) with 531 participants. With respect to habituation, the review indicates the lack of quality articles for habituation inclusion in the narrative synthesis. CONCLUSIONS: The review highlights that selective domains of attention were consistently impaired in individuals with tinnitus. Habituation, on the other hand, needs further exploration.

Transcranial direct current stimulation (tDCS), a treatment option for tinnitus in profound hearing loss.

A 45-year-old man presented with a history of sudden sensory neural hearing loss and severe tinnitus in his left ear. Audiological investigations revealed a profound hearing loss on his left ear and mild conductive hearing loss on his right. Tinnitus pitch and loudness were matched to a 4 kHz narrow-band noise at 50dBHL and subjective tinnitus questionnaires revealed that he had a catastrophic handicap (grade IV). Traditional audiological treatment approaches (tinnitus maskers, hearing aid and sound therapy) that stimulate the cochlea to induce cortical reorganisation were futile. Hence, a top-down approach (transcranial direct current stimulation (tDCS)) to directly modulate the cortical centres was attempted. tDCS was provided for a sum of 15 sessions across 2 phases. There was a substantial improvement in the tinnitus loudness, distress and depression scores which maintained for 3 months post-treatment. tDCS is a potential treatment for phantom perceptions (tinnitus) in cases of profound sensory neural hearing loss where there is no residual sensory ability. Tailor-made approaches seem to be more appropriate until a standard protocol for tDCS in tinnitus is established.

Development and validation of an automated dichotic double word test in Indian English using MATLAB.

OBJECTIVE: Dichotic listening is an experimental paradigm where two different stimuli are presented to the right and left ear simultaneously. Currently, there are no clinically validated full version (Forced recall condition) of dichotic word test in Indian language with established normative. Hence the study involves the development of a MATLAB based Dichotic listening test in Indian English including free recall and forced recall conditions. METHOD: This study was carried out in two phases. Phase 1 involved development and validation of an automated dichotic listening test using MATLAB software. Phase 2 involved data collection and constructing a normative data on 70 healthy adults (18-50 yrs) and 70 children (10-15 yrs) also establishing test retest reliability on 25 participants for the newly developed test. RESULTS: Right ear advantage was observed for free recall condition similar to that of classical dichotic effect. Also, there was no significant difference between the right and left ear scores in the two forced recall condition. The test showed moderate to good test-retest reliability for both the conditions. CONCLUSION: The results showed ideal retention of original dichotic effects for both free recall and forced recall conditions and hence can be used in clinical set to tests disordered population like Central auditory population disorder and Learning disability.

Development and validation of dichotic double digit test in Kannada.

OBJECTIVE: The main objective of the study was to develop, validate and construct norms for a double dichotic digit test in the language 'Kannada' in normal healthy adults, for both free and forced recall conditions. METHOD: This study was carried out in 2 phases. Phase 1 involved the development of the dichotic tests and phase 2 consisted of validation, data collection and normative estimation on 70 normal right-handed adults (18-60 years) and 50 normal children (10-15 years) in both free recall and forced attention condition. RESULTS: The results indicated no significant difference between scores obtained on the three separate lists, in the free recall condition (p = 0.189). There was a significant difference between the right and the left ear scores in all three lists, which indicates a right ear advantage (p = 0.001). In the forced recall condition, there was no significant difference between the right and left ear scores, across the three lists. CONCLUSION: The current study has provided a content-validated double dichotic digit test with normative data in Kannada. Overall the test evaluates right ear advantage with good accuracy.

Sensory and Cognitive Components of Auditory Processing in Individuals With Tinnitus.

Purpose The main purpose of the study is to explore the auditory selective attention abilities (using event-related potentials) and the neuronal oscillatory activity in the default mode network sites (using electroencephalogram [EEG]) in individuals with tinnitus. Method Auditory selective attention was measured using P300, and the resting state EEG was assessed using the default mode function analysis. Ten individuals with continuous and bothersome tinnitus along with 10 age- and gender-matched control participants underwent event-related potential testing and 5 min of EEG recording (at wakeful rest). Results Individuals with tinnitus were observed to have larger N1 and P3 amplitudes along with prolonged P3 latency. The default mode function analysis revealed no significant oscillatory differences between the groups. Conclusion The current study shows changes in both the early sensory and late cognitive components of auditory processing. The change in the P3 component is suggestive of selective auditory attention deficit, and the sensory component (N1) suggests an altered bottom-up processing in individuals with tinnitus.

Cortical auditory evoked potentials and hemispheric specialization of speech in individuals with learning disability and healthy controls: A preliminary study.

Background: Dichotic listening (DL) technique is a behavioral non-invasive tool which is used in studying hemispheric lateralization. Previous studies using behavioral DL have hypothesized that individuals with learning disabilities (LD) exhibit a lack of cortical specialization for processing speech stimulus. However, there is no event related potential (ERP) evidence, hence the main objective of the study is to explore hemispheric asymmetry using cortical auditory evoked potential (CAEPs) in normal hearing adults and also to compare the same in children with LD and healthy controls. Methods: CAEPs were recorded in 16 normal hearing young adults, eight right-handed children with LD and their age matched controls. Two stop constants (/Pa/ - voiceless, bilabial, stop: /Ta/ - voiceless, alveolar, stop) were chosen for this experiment and presented in each ear and dichotically in two different orders (/pa-ta/, /ta-pa/). ERPs were processed using a standard pipeline, and electrodes readings over the left and right hemispheres were averaged to create left and right regions of interest (ROI). The CAEPs were analyzed for mean amplitude and peak latency of P1-N1-P2 components. Results: The current study results suggest no statistically significant difference between the two stimulus in monaural condition and absence of order effect in dichotic condition. In healthy controls the CAEP latencies were shorter over the left hemisphere in both monaural and dichotic conditions in adults and control children. However, it was very evident that such a difference was lacking in children with LD. Conclusions: Hemispheric asymmetry can be detected using CAEPs for speech stimulus. The measures are consistent and void of stimulus or order effect. Taken together, the findings of current study, both monaural and dichotic condition illustrates the hemispheric differences in processing speech stimuli in normal hearers. Absence of latency differences between hemispheres in children with LD indicate a lack of hemispheric asymmetry.