The use of masking level differences in evaluating Central auditory processing: the norms for the normal hearing subjects

Abstract

Objectives: This study sought to determine whether scores of masking level differences MLD were influenced by age and sex and to derive norm values from normal hearing subjects for the Turkish population.Study Design: A total of 100 normal hearing subjects were tested in two age groups. Each group consisted of 25 females and 25 males. The mean ages were 21 range 17 to 24 years and 31 years range 25 to 40 years in group 1 and group 2, respectively. Following pure-tone threshold and speech discrimination tests, the MLD test was performed by using 500 Hz puretone and narrow-band noise centered around 500 Hz.The results were analyzed by the ANOVA test.Results: The mean MLD score was 10.92 dB. The upper and lower limits of MLD scores between two Standard deviations were 6 and 14 dB, respectively.No significant differences were found between MLD scores with regard to age and sex.Gbnclusion: Since MLD scores are not affected by age and sex, the norm values obtained can be utilized in the investigation of some pathologic conditions.

Keywords

• Acoustic stimulation/methods, audiometry, auditory perception, auditory threshold, dichotic listening tests, hearing/physiology, hearing tests, perceptual mask­ing, reference values, speech perception

Merkezi işitsel işlemleme fonksiyonlarının değerlendirilmesinde maskeleme düzeyi farkı testi: Normal işiten gruptan elde edilen norm değerler

Abstract

Amaç: Bu çalıflma, maskeleme düzeyi farkı MDF test skorlarının yafl ve cinsiyetten etkilenip etkilenmediğinin arafltırılması ve normal ifliten kiflilerde ülkemizeait norm değerlerin belirlenmesi amacıyla yapıldı. Çalıflma Planı: Farklı yafl dilimlerindeki 100 denekten iki ayrı grup oluflturuldu. Her bir gruba 25 kadın,25 erkek alındı. Yafl ortalaması grup 1’de 21 , grup 2’de 31 idi. Saf-seseflik odyogramı ve konuflmayı ayırt etme testlerininardından, 500 Hz saf ses uyaranı ve 500 Hz’deodaklanmıfl dar band gürültü kullanılarak MDF testiyapıldı. Sonuçların istatistiksel değerlendirilmesindeANOVA testi kullanıldı. Bulgular: Bütün denekler için ortalama MDF skoru10.92 dB bulundu. Standart sapmanın alt ve üst değerleri 6 ve 14 dB olarak belirlendi. Bulgular MDFtest skorlarının yafl ve cinsiyetten etkilenmediğinigösterdi.Son u ç : Maskeleme düzeyi farkı skorunun yafl ve cinsiyetten etkilenmemesi nedeniyle, bulunan norm değerlerpatolojisi olan grupların arafltırılmasında kullanılabilir

Keywords

• Akustik stimülasyon/yöntem, odyometri, iflitsel algı, iflitme efliği, dikotik dinleme testleri, iflitme/fizyoloji, iflitme testleri, algısal maskeleme, referansdeğerleri, konuflma algısı

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