Speech-in-noise perception in high-functioning individuals with autism or Asperger's syndrome

• Published in: Journal of child psychology and psychiatry Vol. 45; no. 6; pp. 1107 - 1114
• Main Authors: Alcántara, José I., Weisblatt, Emma J.L., Moore, Brian C.J., Bolton, Patrick F.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing 01.09.2004; Wiley-Blackwell; Blackwell; Blackwell Publishing Ltd
• Subjects: Acoustics; Adult; Adult and adolescent clinical studies; Asperger Syndrome; Asperger Syndrome - diagnosis; Asperger's syndrome; Auditory Perception; Auditory Thresholds; Autism; Autism Spectrum Disorders; Autistic Disorder - diagnosis; Autistic people; Background; Biological and medical sciences; British English; Child psychology; Children; Comparative Analysis; dip listening; Female; frequency selectivity; High functioning; Humans; Intellectual deficiency; Intelligence tests; Language; Listening comprehension; Male; Medical sciences; Noise; Noisy environment; Perceptual Impairments; Psychology. Psychoanalysis. Psychiatry; Psychopathology. Psychiatry; Research subjects; Sentences; Signal to Noise Ratio; Sound; Speech; Speech Communication; Speech Perception; Speech Reception Threshold Test; Speech recognition; Speeches; Temporal patterns; temporal resolution and integration; Thresholds; Wechsler Scales; Human; Verbal comprehension; dip listening; frequency selectivity; Deficiency; Interference; Auditory disorder; Developmental disorder; Acoustics; Cognition; speech perception; Hearing loss; Autism; Concomitant disease; Hearing; Asperger syndrome; Asperger's syndrome; Adolescent; Young adult; Ambient noise; Information processing; ENT disease; temporal resolution and integration
• ISSN: 0021-9630; 1469-7610
• DOI: 10.1111/j.1469-7610.2004.t01-1-00303.x

Background:  High‐functioning individuals with autism (HFA) or Asperger's syndrome (AS) commonly report difficulties understanding speech in situations where there is background speech or noise. The objective of this study was threefold: (1) to verify the validity of these reports; (2) to quantify the difficulties experienced; and (3) to propose possible mechanisms to explain the perceptual deficits described. Method:  Speech‐in‐noise perception abilities were measured using speech reception thresholds (SRTs), defined as the speech‐to‐noise ratio (SNR) at which approximately 50% of the speech is correctly identified. SRTs were measured for 11 individuals with HFA/AS and 9 age/IQ‐matched normal‐hearing control subjects, using an adaptive procedure, in a non‐reverberant sound‐attenuating chamber. The speech materials were standardised lists of everyday sentences spoken by a British male speaker. The background sounds were: (1) a single female talker; (2) a steady speech‐shaped noise; (3) a speech‐shaped noise with temporal dips; (4) a steady speech‐shaped noise with regularly spaced spectral dips; and (5) a speech‐shaped noise with temporal and spectral dips. Results:  SRTs for the HFA/AS group were generally higher (worse) than those for the controls, across the five background sounds. A statistically significant difference in SRTs between the subject groups was found only for those background sounds that contained temporal or spectro‐temporal dips. SRTs for the HFA/AS individuals were 2 to 3.5 dB higher than for the controls, equivalent to a substantial decrease in speech recognition. Expressed another way, the HFA/AS individuals required a higher SNR, whenever there were temporal dips in the background sound, to perform at the same level as the controls. Conclusions:  The results suggest that the speech‐in‐noise perception difficulties experienced by individuals with autism may be due, in part, to a reduced ability to integrate information from glimpses present in the temporal dips in the noise.