Pruebas de fusión auditiva y de detección de gaps: evaluación de la resolución auditiva temporal / Auditory fusion and gap detection tests: assessment of auditory temporal resolution

RESUMEN Dentro de los distintos mecanismos del procesamiento auditivo, los aspectos temporales de la audición se consideran como uno de los más relevantes ya que serían la base para el adecuado funcionamiento del resto de los procesos auditivos centrales. Los aspectos temporales de la audición se definen como los procesos implicados en la percepción del sonido y de sus variaciones en el dominio temporal. Uno de los aspectos temporales más ampliamente estudiados, por su relevancia en la percepción y discriminación de los sonidos del habla, ha sido la resolución auditiva temporal, que se refiere a la mínima cantidad de tiempo necesaria para que un individuo pueda discriminar entre dos estímulos auditivos distintos. En los últimos años, se ha utilizado principalmente metodologías de detección de fusión auditiva y detección de gaps para su evaluación. Ambas han dado origen a una serie de pruebas psicoacústicas, de las cuales destacan tres: la prueba de fusión auditiva revisada, la prueba de detección de gaps aleatorios y la prueba de gaps en ruido. Se recomienda la incorporación de alguna de estas pruebas en la evaluación clínica ante la sospecha de trastornos del procesamiento auditivo.

ABSTRACT Among the different mechanisms of auditory processing, the temporal aspects of hearing are considered as one of the most relevant since they would be the basis for the proper functioning of the rest of the central auditory processes. Temporal aspects of hearing are defined as the processes involved in the perception of sound and its variations in the temporal domain. One of the most widely studied temporal aspects due to its relevance in the perception and discrimination of speech sounds has been the temporal auditory resolution, which refers to the minimum amount of time necessary for an individual to discriminate between two different auditory stimuli. In recent years, the mainly used methodologies for evaluate it are the hearing fusion detection and gaps detection. Both methodologies have given rise to several psychoacoustic tests, of which three have been highlighted: the revised auditory fusion test, the random gap detection test and gaps in noise test. It is recommended the incorporation of any of these tests in the clinical evaluation of suspected auditory processing disorders.

Resolución temporal visual en pacientes con anemia drepanocítica / Visual temporal resolution in patients with sickle cell anemia / Resolução temporal visual em pacientes com anemia drepanocítica

El desarrollo del Sistema Nervioso (SN) está afectado en los pacientes con Anemia Drepanocítica (AD). La Resolución Temporal Visual (RTV) es considerada como una medida de la velocidad de procesamiento y de activación cortical. Se utiliza como indicador general del funcionamiento del SN y puede evaluarse mediante la Frecuencia Crítica de Fusión (FCF). Se midió la FCF en 84 pacientes sin antecedentes de eventos neurológicos, en edades entre 8-68 años, y en controles sanos. Se midió el valor de la hemoglobina (Hb) de los pacientes al momento de la evaluación neuropsicológica. La FCF de los pacientes fue significativamente más baja. La edad correlacionó inversamente con la FCF; no se hallaron associaciones estatisticamente significativas entre los valores de la Hb y los resultados de la FCF. Se concluye que la RTV está disminuida en los pacientes con AD, lo que sugiere la existencia de afectación del neurodesarrollo como resultado de la enfermedad.

The Nervous System (NS) is affected in patients with Sickle Cell Anemia (SCA). The Visual Temporal Resolution (VTR) is considered as a measure of processing speed and cortical activation. It is used as general indicator of NS functioning, and it can be tested by Critical Frequency Fusion (CFF). The CFF was examined in 84 patients without previous neurologic events and the same amount in healthy subjects. The participants were ranging in age from 8 to 68. The patients' hemoglobin level was measured at the moment of the neuropsychological assessment. The patients' CFF was significantly lower than healthy people. Age correlated inversely with CFF, and statistically significant associations between hemoglobin and CFF was not found. We concluded that VTR is diminished en patients with SCA, which suggests that neurodevelopment is affected due to SCA.

O desenvolvimento do Sistema Nervoso (SN) está afetado nos pacientes com Anemia Drepanocítica (AD). A Resolução Temporal Visual (RTV) é considerada uma medida da velocidade de processamento e de ativação cortical. Como indicador geral do funcionamento do SN essa medida é utilizada e pode ser mensurada mediante a Frequência Crítica de Fusão (FCF). Foi verificada a FCF em uma amostra de 84 pacientes sem antecedentes de eventos neurológicos, com idades entre 8 e 68 anos e em controles sadios. Mensurou-se o valor da hemoglobina (Hb) dos pacientes durante a avaliação neuropsicológica. A FCF dos pacientes foi significativamente mais baixa. A idade correlacionou inversamente com a FCF; não foram encontradas associações estatisticamente significativas entre os valores da hemoglobina e os resultados da FCF. Conclui-se que a RTV está diminuída nos pacientes com AD sugerindo que há afetação do neurodesenvolvimento como resultado da doença.

Audiological Profile of Adult Persons with Auditory Neuropathy Spectrum Disorders

BACKGROUND AND OBJECTIVES: The auditory profile of a large number of persons with late onset auditory neuropathy spectrum disorder (ANSD) is recently described in the Indian context. The purpose of study was 1) to profile data on routine audiological parameters, cortical evoked potentials, and temporal processing, 2) to analyze the benefit from hearing aids for persons with ANSD, and 3) to understand the association between benefit from hearing aids and auditory profile. SUBJECTS AND METHODS: Thirty-eight adults with late onset ANSD and a matched group of 40 normally hearing adults participated in the study. Basic audiological tests, recording of cortical evoked potentials, and temporal processing tests were carried out on both groups of participant while only persons with ANSD were fitted with hearing aid. RESULTS: Subjects in the two groups were significantly different on all the audiological parameters. ANSD group seemed to benefit from hearing aids variably. The mean amplitude of N2 was significantly different between normally-hearing participants and patients with ANSD. CONCLUSIONS: Residual temporal processing, particularly amplitude modulation detection seems to be associated with benefit from hearing aids in patients with ANSD.

Effect of temporal resolution of breast dynamic contrast-enhancing MRI on pharmacokinetic parameters / 中华放射学杂志

Objective To evaluate the effect of temporal resolution of breast dynamic contrast-enhancing (DCE)-MRI on pharmacokinetic parameters and diagnostic performance in benign and malignant breast lesions.Methods Retrospective review was performed on 26 benign and 29 malignant breast lesions which were proven pathologically by surgery or biopsy.Dynamic contrast enhanced breast MRI using a new volume-interpolated-breath-hold examination sequence combining parallel acquisition, Dixon fat separation and time-resolved imaging with interleaved stochastic trajectories (CDT-VIBE) was performed in all patients.The original time resolution of this sequence was 12 s and based on which, dynamic sequences with different temporal resolutions of 24 s, 36 s, 48 s and 60 s were simulated by a sample-removing method and were used for the calculation of pharmacokinetic parameters, including volume transfer constant (Ktrans), constant flux rate (Kep), volume of extravascular extracellular space (Ve) and area under the curve at initial 60 s (iAUC), to observe their changes with different temporal resolution.The repeated measurement of analysis of variance was used to explore significant changes in pharmacokinetics parameters with different temporal resolution.To evaluate the diagnostic efficiency of parameters with different temporal resolution, ROC analysis was performed in accordance with pathological findings.Results With decrease of temporal resolution from 12 to 60 s, there was a significant increase in Ktrans and Kep of benign lesions [Ktrans: (0.147±0.084)/min to (0.170 ± 0.085)/min, Kep: (0.321± 0.176)/min to (0.433± 0.175)/min] and steady decrease in Ktrans and Kep of malignant lesions [Ktrans: (0.373±0.210)/min to (0.259± 0.122)/min, Kep: (0.929 ±0.402)/min to (0.581 ± 0.143)/min];the changes of Ve were less significant and irregular;the values of iAUC decreased both in benign [(9.192± 4.660) to (7.388± 3.065)] and malignant [(20.221±9.876) to (12.850±5.194)] lesions.The changes in all parameters with different time resolution were statistically significant in benign and malignant lesions (all P＜0.05).By pair-wise comparison between different time resolution, the changes of K among 12 s, 24 s and 36 s (all P＜0.05), the changes of Kep between 12 s and others (all P＜0.01), the changes of Ve between 24 s and others (all P＜0.01), and the changes among all pairs of iAUC were significant (all P＜0.05) except for 12 s and 24 s (P=1.000).The best AUC value of Ktrans and Kep between benign and malignant lesions were achieved with 12 s dynamic sequences (0.887, 0.939), and the best AUC value of iAUC was with 24 s sequences (0.877).The AUC values of Ve were between 0.511 to 0.601, which was lower than that of other three parameters.Conclusion A 24 s or higher temporal resolution of DCE-MRI should be able to provide consistent differentiation of pharmacokinetic parameters in benign and malignant breast lesions.

The Effect of High Frequency Sensorineural Hearing Loss on Auditory Temporal Resolution: Gaps-In-Noise Test Performance in Older and Young Adults with Normal Hearing / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Auditory temporal resolution, which refers to the time-related aspects of acoustic processing, can be evaluated by the Gaps-In-Noise (GIN) test. We investigated whether the presence of high frequency sensorineural hearing loss (HF-SNHL) affects the temporal resolution of GIN performance in older adults with normal hearing. SUBJECTS AND METHOD: Hearing tests including the GIN test were performed in 87 subjects with normal pure tone average. The GIN threshold and percentage of correct answers were compared among 4 groups of participants; older adults with normal hearing (n=18), older adults with HF-SNHL (n=24), young adults with normal hearing (n=24) and young adults with HF-SNHL (n=21). RESULTS: There was no significant difference in the mean GIN thresholds between the HF-SNHL group (5.8+/-0.8 msec) and the normal hearing group (6.0+/-0.8 msec) in older adults, whereas the mean GIN thresholds of HF-SNHL group was higher than that of the normal group in young adults (4.6+/-0.3 msec vs. 4.2+/-0.5 msec, p<0.05). The mean percentage of correct answers of HF-SNHL group (62.5+/-5.5%) was not significantly different from that of the normal hearing group (60.6+/-3.9%) in the old, unlike in the young (71.3+/-4.0% with HF-SNHL vs. 76.9+/-4.3% with normal hearing, p<0.05). Age only showed a significant correlation with the GIN performance. Neither the GIN threshold nor the GIN perception level had any relation with the presence of HF-SNHL in older adults. CONCLUSION: We found no evidence that supported the influence of HF-SNHL on auditory temporal resolution in older adults. These results imply that HF-SNHL may be of little importance in gap detection after age-related changes in central auditory system.

Effects of changing temporal resolution of spiral computed tomography on perfusion of cervical cancer and radiation dose / 西安交通大学学报(医学版)

Objective To study the effects of different temporal resolution of spiral computed tomography (CT)on perfusion parameters and perfusion curve of cervical cervical cancer.Methods Ten cases of cervical cancer were clinically confirmed with CT perfusion scanning.The original data were acquired using temporal resolution of 0.75 s.Then the original data were grouped according to different temporal resolution,namely,1.5 s group,2.25 s group,3 s group,3.75 s group,4.5 s group,5.25 s group,and 6 s group (experiment group). According to the same mathematical model and ROI of the same part,perfusion parameters (BF,BV,MTT,and PS)in each group were calculated respectively and compared with the original data.Results BF and MTT were relatively sensitive to the change of temporal resolution.When the temporal resolution was 3 s,it had a significant impact.PS and BV were not so sensitive to the change of temporal resolution.Temporal resolution of 4.5 s had a significant effect on PS. There was a significant effect on BV until the temporal resolution was 5.25 s. Conclusion Changing the temporal resolution will lead to corresponding changes of perfusion curve and perfusion parameters.Under the premise that it does not affect the diagnosis,properly decreasing temporal resolution (circu-lar scanning temporal ≤2.25 s)of CT perfusion scanning of cervical cancer can reduce the radiation dose effectively.

The Effects of Unilateral Tinnitus on Auditory Temporal Resolution: Gaps-In-Noise Performance

BACKGROUND AND OBJECTIVES: The Gaps-In-Noise (GIN) test is a measure to assess auditory temporal resolution, which is the ability to follow rapid changes in the envelope of a sound stimulus over time. We investigated whether unilateral tinnitus affects temporal resolution by the GIN performance. SUBJECTS AND METHODS: Hearing tests including the GIN test were performed in 120 ears of 60 patients with unilateral tinnitus who showed symmetric hearing within 20 dB HL difference up to 8 kHz (tinnitus-affected ears, 14.6+/-11.2 dB HL; non-tinnitus ears 15.1+/-11.5 dB HL) and 60 ears of 30 subjects with normal hearing. Comparisons were made between tinnitus and non-tinnitus side of patients and normal ears of controls. RESULTS: There was no significant difference of the mean GIN thresholds among tinnitus-affected ears (5.18+/-0.6 ms), non-tinnitus ears (4.98+/-0.6 ms) and normal ears (4.97+/-0.8 ms). The mean percentage of correct answers in tinnitus side (67.3+/-5.5%) was slightly less than that in non-tinnitus side (70.0+/-5.5%) but it was not significantly different from that in normal ears (69.4+/-7.5%). Neither the GIN threshold nor the GIN perception level in tinnitus ears has relation to sex, frequency and loudness of tinnitus, and audiometric data. Age only showed a significant correlation with the GIN performance. CONCLUSIONS: We found no evidence which supported the influence of unilateral tinnitus on auditory temporal resolution. These results imply that tinnitus may not simply fill in the silent gaps in the background noise.

Evaluación de la discriminación del habla y resolución temporal en un grupo de adultos mayores hispanohablantes / Assessment of speech discrimination and temporal resolution in a group of spanish-speaking senior citizens

El objetivo del presente estudio fue explorar la relación entre la resolución temporal y la discriminación del habla tanto en silencio como en ruido. Treinta sujetos adultos mayores fueron seleccionados. Ninguno de ellos presentó antecedentes de patología de oído medio, diabetes, insuficiencia renal, exposición ocupacional a ruido y enfermedad neurológica. Todos los sujetos seleccionados fueron evaluados a través de los procedimientos de audiometría tonal liminal, Random Gap Detection test (RGD), máximo porcentaje de discriminación de monosílabos (MAX), y Hearing-in-Noise test (HINT). El grupo en estudio fue dividido en dos subgrupos de acuerdo a si presentaban o no audición normal para su edad (ISO 7029). Se encontraron diferencias estadísticamente significativas en los puntajes de las pruebas entre ambos subgrupos. Se observó que los sujetos del estudio presentaron resultados descendidos de acuerdo a las normas reportadas para la prueba de RGD y HINT, inclusive los sujetos con audición normal para su edad, Se discuten las implicancias clínicas de estos hallazgos y la importancia de la resolución temporal en tareas de discriminación de habla.

The present study aimed to explore a possible association between temporal resolution and speech discrimination in both quiet and noise in a group of older adults. Thirty subjects were selected for study purposes. All of them had absence of middle-ear patology, diabetes, kidney failure, occupational noise exposure and neurological disease. Pure-tone audiometry, Random Gap Detection test (RGD), Maximun percentage of discrimination of monosyllables (MAX) and hearing-in-noise test (HINT)were carried out. Study group subjects were divided into two subgroups according to whether or not their hearing level was within normal ranges adjusted for age (ISO 7029). Significant differences for tests scores were found between groups. When the subgroup of subjects with normal-hearing thresholds was compared to the norms reported for RGDT and HINT, scores obtainedby these subjects were below the norms. Clinical implications of these results and the role of temporal resolution in speech descrimination tasks are discussed.