Comodulation masking release effect in children with and without dyslexia

Sovon Dhara, Indranil Chatterjee, Himansu Kumar, Susmi Pani


Background: Speech recognition in a modulating noise background can be facilitated by a process attributable to comodulation masking release (CMR). CMR is usually assumed to depend on comparisons of the outputs of different auditory filters. There was an immense importance to study to find the CMR effect in children with and without dyslexia.

Methods: The study was to find the CMR effect in children with and without dyslexia. The current research was carried out through five steps i.e. auditory attention task stimuli preparation, auditory performance test, CMR stimuli preparation, CMR task and statistical analysis. Through these processes for measuring the CMR was done for the children with and without dyslexia. All the data were tabulated and statistically computed for the analysis of the data. SPSS software version 16 was used for the statistical analysis of the data.  

Results: Independent t-test was used for the statistical analysis while the comparison between groups. Paired t- test was used for the statistical analysis while the comparison within the group at 95% confidence interval. These results indicated that the amount effect of CMR is greater in children with dyslexia. There was not a significant difference of CMR between the children with and without dyslexia to the effect of CMR was not significantly different between the ears in children without dyslexia and with dyslexia.

Conclusions: The present study indicates that children with dyslexia have selective inability to use the temporal and spectral cues necessary for signal extraction in CMR.


Comodulation masking release, Masking, Dyslexia, Noise, Auditory performance

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Wegel R, Lane C. The Auditory Masking of One Pure Tone by Another and its Probable Relation to the Dynamics of the Inner Ear. Physical Review. 1924;23(2):266-85.

Durrant JD, Lovrinic JH. Bases of Hearing Science, Williams and Wilkins; 1995.

Schooneveldt G, Moore B. Comodulation masking release (CMR): Effects of signal frequency, flanking‐band frequency, masker bandwidth, flanking‐band level, and monotic versus dichotic presentation of the flanking band. The Journal of the Acoustical Society of America. 1987;82(6):1944-56.

Verhey J, Dau T, Kollmeier B. Within-channel cues in comodulation masking release (CMR): Experiments and model predictions using a modulation-filterbank model. J Acoustical Society Am. 1999;106(5):2733-45.

Snowling MJ. Dyslexia. Blackwell Publishing; 2000.

Hartley D, Moore D. Auditory processing efficiency deficits in children with developmental language impairments. J Acoustical Society Am. 2002;112(6):2962-6.

Tallal P. Auditory temporal perception, phonics, and reading disabilities in children. Brain Language. 1980;9(2):182-98.

Gu X, Green D. Further studies of a maximum‐likelihood yes–no procedure. J Acoustical Society Am. 1994;96(1):93-101.

Pierzycki RH, Seeber BU. Comodulation masking release in electric hearing. J Association Res Otolaryngol. 2014;15(2):279-91.

Bee MA, Buschermöhle M, Klump GM. Detecting modulated signals in modulated noise:(II) neural thresholds in the songbird forebrain. European J Neurosci. 2007;26(7):1979-94.

Zettler C, Sevcik R, Morris R, Clarkson M. Comodulation Masking Release (CMR) in Children and the Influence of Reading Status. J Speech Language Hearing Res. 2008;51(3):772-84.

Swanson H. Reading Comprehension and Working Memory in Learning-Disabled Readers: Is the Phonological Loop More Important Than the Executive System?. J Experimental Child Psychol. 1999;72(1):1-31.

Kimura D. Cerebral dominance and the perception of verbal stimuli. Canadian J Psychology/Revue Canadienne De Psychologie. 1961;15(3):166-71.

Mott J, McDonald L, Sinex D. Neural correlates of psychophysical release from masking. J Acoustical Society Am. 1990;88(6):2682-91.

Moore B, Shailer M, Schooneveldt G. Temporal modulation transfer functions for band-limited noise in subjects with cochlear hearing loss. Br J Audiol. 1992;26(4):229-37.

Banai K, Ahissar M. Auditory Processing Deficits in Dyslexia: Task or Stimulus Related?. Cerebral Cortex. 2005;16(12):1718-28.