Effect of Speech Degradation and Listening Effort in Reverberating and Noisy Environments Given N400 Responses

Kyong Jeong-Sug,곽찬범,Han Woojae,서명환,김진숙 대한청각학회 2020 Journal of Audiology & Otology Vol.24 No.3

Background and Objectives: In distracting listening conditions, individuals need to pay extra attention to selectively listen to the target sounds. To investigate the amount of listening effort required in reverberating and noisy backgrounds, a semantic mismatch was examined.Subjects and Methods: Electroencephalography was performed in 18 voluntary healthy participants using a 64-channel system to obtain N400 latencies. They were asked to listen to sounds and see letters in 2 reverberated×2 noisy paradigms (i.e., Q-0 ms, Q-2000 ms, 3 dB-0 ms, and 3 dB-2000 ms). With auditory-visual pairings, the participants were required to answer whether the auditory primes and letter targets did or did not match. Results: Q-0 ms revealed the shortest N400 latency, whereas the latency was significantly increased at 3 dB-2000 ms. Further, Q-2000 ms showed approximately a 47 ms delayed latency compared to 3 dB-0 ms. Interestingly, the presence of reverberation significantly increased N400 latencies. Under the distracting conditions, both noise and reverberation involved stronger frontal activation. Conclusions: The current distracting listening conditions could interrupt the semantic mismatch processing in the brain. The presence of reverberation, specifically a 2000 ms delay, necessitates additional mental effort, as evidenced in the delayed N400 latency and the involvement of the frontal sources in this study.

The Entropic Brain: Effortful Speech Reflected in Organisation of the Network Graph

( Jeong Sug Kyong ),( Chun Kee Chung ),( June Sic Kim ) 서울대학교 인지과학연구소 2015 Journal of Cognitive Science Vol.16 No.1

Uncertainty of incoming information increases the amount of mental effort. Scientists might have been interested in quantifying the amount of this mental effort, as evidenced by the great amount of research devoted to computing the energy used to deal with the uncertainty of an event. One of these measures is Shannon’s entropy, which was initially used as a measure of the level of uncertainty with respect to the outcome of an event (Shannon, 1948). As defined by Shannon, entropy is expected to increase as the level of disorder (uncertainty or task complexity) increases. Therefore, to evaluate how the brain deals with entropy, one could either locate the focal area showing activity that is positively correlated with the degree of uncertainty or consider information transfer. We speculated that a functionally effective brain would modulate its network to fit to the varying entropy, since computation in the brain is probabilistic. Therefore, we put forward two hypotheses: 1) the functional brain architecture will reflect the varying entropy, and 2) the entropy will be modality-specific. In order to test these hypotheses, we estimated several network properties of the magnetoencephalography time-series signals obtained from healthy monolingual listeners. We particularly focused on whether entropy reflects the modality-specific processing load, especially when the degrees of the processing load of the two events were similar in terms of the rate of accuracy and the length of response time between tasks. In order to manipulate both entropy and modality, we varied the processing complexity (easy vs. difficult) in either a linguistic or non-linguistic (pitch change detection vs. word intelligibility test) task. Using graph-theoretical measures, the global organisation measures of the network, such as its small-worldness, correlation coefficient, global efficiency, and characteristic path-lengths, were compared within the network extracted as a set of 78 brain atlas nodes. The results showed a significant main effect of task complexity on the brain network properties, demonstrating that task load is indeed ubiquitous regardless of task modality. Equally importantly, we also found a pronounced task-specific difference in the network properties between linguistic and non-linguistic modalities. Regardless of modality, in the effortful tasks, the characteristic path-length and the correlation-coefficient were significantly larger, whereas the linguistic tasks resulted in significantly higher small-worldness, with the hubs located at the usual language nodes. Our findings collectively suggest that task load is ubiquitous but is also modality-specific in the brain network properties, as evidenced by the specific network graph measures.

Development of Korean Music Rehabilitation Program for Persons with Hearing Loss

Yerim Shin,Jeong-Sug Kyong,Sungmin Jo,Jinsook Kim 한국청각언어재활학회 2022 Audiology and Speech Research Vol.18 No.2

Purpose: The ability of music perception should be improved for the hearing impaired by music training. The music training should be systematically conducted from each musical element to overall music listening based on analytic and synthetic approaches. This study aimed to develop the music rehabilitation program (MRP) to improve the music perception of the hearing-impaired. Methods: Fifteen cochlear implant (CI) users (34.5 ± 11.6 years) participated. The MRP consisted the musical elements such as pitch, melody, rhythm and timbre, and musical emotional training considering Korean culture. The MRP was conducted twice per week through self-directed home training for 2 months. The assessment of music perception (AMP) was tested before and after performing the MRP. Results: The results of AMP subtests were significantly different between pre- and post-MRP with 61.1% and 83.8% for the pitch perception test, 72.8% and 87.8% for the timbre perception test with Korean musical instruments, 48.0% and 59.3% with Western musical instruments, and 55.9% and 71.1% in the harmony perception test. However, there was no significant differences in the melody, rhythm and emotional reaction tests. According to the MRP effectiveness questionnaire, 80% of participants have changed their interests after training for listening to music. Conclusion: Although there were differences among elements of music training, the overall music perception ability was improved after conducting MRP (p < 0.001). In conclusion, providing a systematic music training program such as MRP could expand the range of music experience and improve the ability for music listening and for CI users.

Music Perception Abilities of the Hearing Amplification System Users

Jo Sungmin,Yun Jiyeong,Kyong Jeong-Sug,Shin Yerim,Kim Jinsook 대한청각학회 2023 Journal of Audiology & Otology Vol.27 No.2

Background and Objectives: Recently, the improvement of music perception abilities for emotional stability and high quality of life has become important for the hearing loss group. This study aimed to examine and compare the music perception abilities of the normal hearing (NH) and hearing amplification system (HAS) groups to find the needs and methods of music rehabilitation.Subjects and Methods: The data were collected from 15 NH adults (33.1±11.4 years) and 15 HAS adults (38.7±13.4 years), of whom eight wore cochlear implant [CI] systems and seven wore CI and hearing aid systems depending on pitch, melody, rhythm, timbre, emotional reaction, and harmony perception tests. A mismatch negativity test was also conducted, and attitudes toward and satisfaction with listening to music were measured.Results: The correction percentages for the NH and HAS groups were 94.0%±6.1% and 75.3%±23.2% in the pitch test; 94.0%±7.1% and 30.3%±25.9% in the melody test; 99.3%±1.8% and 94.0%± 7.6% in the rhythm test; 78.9%±41.8% and 64.4%±48.9% in the timbre test; 96.7%±10.4% and 81.7%±16.3% in the emotional reaction test; and 85.7%±14.1% and 58.4%±13.9% in the harmony test, respectively, showing statistical significance (<i>p</i><0.05). For the mismatch negativity test, the area of the waveform was smaller in the HAS groups than in the NH groups, with 70 dB of stimulation showing no statistical significance. The response rates for satisfaction with listening to music were 80% and 93.3% for the NH and HAS groups, showing no statistical significance.Conclusions: Although the HAS group showed lower music perception ability than the NH group overall, they showed a strong desire for music listening. Also, the HAS group revealed a higher degree of satisfaction even when listening to unfamiliar music played with unusual instruments. It is suggested that systematic and constant musical rehabilitation based on musical elements and different listening experiences will improve music perception qualities and abilities for HAS users.

Development of Assessment of Music Perception for the Hearing-impaired

Yerim Shin,Jiyeong Yun,Jeong-Sug Kyong,Sungmin Jo,Jinsook Kim 한국청각언어재활학회 2021 Audiology and Speech Research Vol.17 No.4

Purpose: Enhancement of musical perception has a positive impact on the emotional stability, quality of life, and aural rehabilitation in individuals with hearing loss. In Korea, however, there are a few test batteries available for properly assessing their abilities to perceive music. The purpose of this study was to develop a evaluation material for the music perception ability, Assessment of Music Perception (AMP) considering the Korean culture and emotion. Methods:A total of 15 normal hearing adults (33.1 ± 11.4 years) were recruited. They performed the AMP which includes eight sub-tests: pitch, melody, rhythm, timbre, and harmony perception test, emotional reaction test, Music listening Atti-tudes and Satisfaction Questionnaire (MASQ), and Mismatch negativity (MMN). Results:The average percentage of correct answer was 94.0% ± 6.1% in pitch perception test, 94.0% ± 7.1% in melody perception test, 99.3% ± 1.8% in rhythm perception test, 78.9% ± 41.8% in timbre perception test, 96.7% ± 10.4% in emotional reaction test, 85.7% ± 14.1% in harmony perception test. The area of the negative waveform for MMN was 275.27 ± 225.65 μV·ms with the intensity of 70 dBnHL. Conclusion: Considering high scores of a instrument, a developed AMP could be applied for evaluating the music perception ability. However, a little bit of correction for each factor of materials is recommended for comprehensive AMP material. In the future, the music perception ability of the hearing impaired should be evaluated utilizing AMP.

Comparison of Treatment Outcomes Following Either Prefrontal Cortical-only or Dual-site Repetitive Transcranial Magnetic Stimulation in Chronic Tinnitus Patients: A Double-blind Randomized Study

Noh, Tae-Soo,Kyong, Jeong Sug,Chang, Mun Young,Park, Moo-Kyun,Lee, Jun-Ho,Oh, Seung-Ha,Kim, June Sic,Chung, Chun Kee,Suh, Myung-Whan Lippincott Williams Wilkins 2017 Otology & Neurotology Vol.38 No.2

<P>Conclusions: The rTMS protocol effectively suppressed tinnitus in the dual-site rTMS (AC + FC) group but not in the single-site rTMS (DLPFC) group. Although recent evidence has shown that non-auditory cortices in the tinnitus network play an important role in the generation of tinnitus, our findings indicate that rTMS on non-auditory cortical sites alone may not be sufficient for treatment. Thus, dual-site rTMS in the AC and DLPFC may be preferable for controlling this condition.</P>

A Study of Music Training for Cochlear Implant Users: Mismatch Negativity and Music Listening Attitude and Satisfaction Questionnaire

Yerim Shin,Chaeyeon Yu,Sungmin Jo,Jeong-Sug Kyong,Jinsook Kim 한국청각언어재활학회 2022 Audiology and Speech Research Vol.18 No.3

Purpose: The music rehabilitation program (MRP) promotes auditory, language, cognitive, and motor development of the brain. The significance of MRP was studied through mismatch negativity (MMN) and Music Listening Attitude and Satisfaction Questionnaire for hearing loss (MASQ_H). Methods: Fifteen adult cochlear implant (CI) users (34.5 years; standard deviation, ± 11.6) participated. MMN was tested before and after MRP training at the stimulus intensity level of 70 and 100 dB hearing loss (HL). In addition, MASQ_H was utilized. Results: For the pre- and post-tests of MMN, the average amplitudes of the waveforms were -2.48 ± 1.95 μV and -6.11 ± 4.21 μV and the areas were 208.16 ± 211.59 μV·ms and 527.87 ± 360.42 μV·ms with the significant difference when the stimulus level was presented at 70 dB HL. For MASQ_H, 90.9% of the participants responded that they felt satisfied with listening to music using CI or hearing aid. When asked about the musical factors that were improved in the music listening, the ‘pitch perception’ and ‘timbre perception’ were responded showing increased satisfaction rates. Conclusion: This study confirmed that MRP improved language processing by facilitating auditory processing, cognitive ability, and neural plasticity of the central auditory system through the increased amplitude and area of MMN after MRP application. Furthermore, providing a systematic music training such as MRP could change the music listening attitudes and satisfaction of the CI users’. The active implementation of music rehabilitation is strongly suggested.

Time Perception and Memory in Mild Cognitive Impairment and Alzheimer’s Disease: A Preliminary Study

Woo Sung-Ho,Hahm Jarang,Kyong Jeong-Sug,Kim Hang-Rai,Kim Kwang Ki 대한치매학회 2023 Dementia and Neurocognitive Disorders Vol.22 No.4

Background and Purpose: Episodic memory is a system that receives and stores information about temporally dated episodes and their interrelations. Our study aimed to investigate the relevance of episodic memory to time perception, with a specific focus on simultaneity/order judgment. Methods: Experiment 1 employed the simultaneity judgment task to discern differences in time perception between patients with mild cognitive impairment or dementia, and age-matched normals. A mathematical analysis capable of estimating subjects’ time processing was utilized to identify the sensory and decisional components of temporal order and simultaneity judgment. Experiment 2 examined how differences in temporal perception relate to performance in temporal order memory, in which time delays play a critical role. Results: The temporal decision windows for both temporal order and simultaneity judgments exhibited marginal differences between patients with episodic memory impairment, and their healthy counterparts (p = 0.15, t(22) = 1.34). These temporal decision windows may be linked to the temporal separation of events in episodic memory (Pearson’s ρ = −0.53, p = 0.05). Conclusions: Based on our findings, the frequency of visual events accumulated and encoded in the working memory system in the patients’ and normal group appears to be approximately (5.7 and 11.2) Hz, respectively. According to the internal clock model, a lower frequency of event pulses tends to result in underestimation of event duration, which phenomenon might be linked to the observed time distortions in patients with dementia.

Comparison of treatment outcomes between 10 and 20 EEG electrode location system-guided and neuronavigation-guided repetitive transcranial magnetic stimulation in chronic tinnitus patients and target localization in the Asian brain

Noh, Tae-Soo,Rah, Yoon-Chan,Kyong, Jeong Sug,Kim, June Sic,Park, Moo Kyun,Lee, Jun Ho,Oh, Seung Ha,Chung, Chun Kee,Suh, Myung-Whan Informa UK (Taylor Francis) 2017 Acta oto-laryngologica Vol.137 No.9

작업기억용량 및 인지부하가 단어 재인에 미치는 영향에 대한 청년과 노년 집단 간 수행비교: 시선추적 연구

유민아(Min Ah Yoo),오승하(Seung Ha Oh),경정숙(Jeong Sug Kyong),성지은(Jee Eun Sung) 한국언어청각임상학회 2021 Communication Sciences and Disorders Vol.26 No.2

배경 및 목적: 본 연구는 청년과 노년을 대상으로 작업기억용량과 인지부하 정도의 차이가 단어 재인 능력에 미치는 영향에 대해 시선추적기법을 통해 알아보고자 하였다. 방법: 청년과 노년 집단별로 24명씩, 총 48명이 본 실험에 참여하였으며, 세부적으로 각 집단 내에서 작업기억용량(고, 저) 집단으로 분류하였다. 본 연구는 인지부하 조건(고, 저)인 숫자 외우기 과제와 단어 재인 과제를 실시하였다. 본 연구의 결과에 대해 오프라인 측정변수인 반응정확도, 반응시간, 온라인 측정변수인 시선고정비율로 나누어 분석하였다. 결과: 반응정확도 및 반응시간의 경우, 단어 재인 과제에서 청년 및 노년 집단 간 주효과가 유의하였다. 추가로 반응시간의 경우, 작업기억용량에 따른 인지부하 조건 간 이차상호작용이 유의하였다. 시선고정비율의 경우, 집단 간 주효과가 유의하였다. 또한, 시간 구간에 따른 집단 간, 인지부하 조건 간 이차상호작용이 유의하였으며, 시간 구간별 인지부하 조건 및 집단 간 삼차상호작용도 유의하였다. 논의 및 결론: 반응정확도와 달리 반응시간, 시선고정비율은 집단 간 차이 이외에 인지부하, 작업기억용량 요인과의 상호작용효과가 유의하였다. 이를 통해 언어처리는 인지부하, 작업기억용량 같은 복합적인 요인이 영향을 미쳤음을 간접적으로 시사한다. 더 나아가 언어 처리과정에 대해 반응정확도 측정만으로는 충분하지 않다. 따라서 오프라인 측정변수와 함께 온라인 측정변수를 통해 노화, 작업기억용량, 인지부하 조건과 단어 재인 능력에 대한 연관성을 확인할 수 있음을 보여준다. Objectives: The purpose of the study was to identify the impact of age-related working memory capacity and cognitive load to word recognition using an eye tracker. Methods: A total of 48 participants (24 young, 24 elderly adults) who were divided according to working memory capacity (high, low) participated in the study. This study consisted of a digit load and word recognition task. Results: First, the elderly group had lower accuracy and slower response times than the young group. There was a significant difference between working memory capacity and cognitive load in response time. In the group with low working memory capacity, the response time increased under lower cognitive load, which was different from the group with a high working memory capacity. Next, the elderly group had a lower proportion of fixation than the young group by time interval. In addition, there was a significant interaction between group and cognitive load by time interval. In particular, the proportion of fixation decreased over time under a high cognitive load while the proportion of fixation increased under a low cognitive load in the elders, because the inhibition and switching abilities were weakened which made the elders unable to process information efficiently. Conclusion: The study results showed significant effects between working memory capacity and cognitive load in response time and proportion of fixation. This implies that complex factors influence language processing, which makes measuring accuracy insufficient. Thus, this research confirms the correlation among aging, working memory, and cognitive load through both online and offline measurement.