Speech and Non-Speech Audio-Visual Illusions: A Developmental Study

Abstract

It is well known that simultaneous presentation of incongruent audio and visual stimuli can lead to illusory percepts. Recent data suggest that distinct processes underlie non-specific intersensory speech as opposed to non-speech perception. However, the development of both speech and non-speech intersensory perception across childhood and adolescence remains poorly defined. Thirty-eight observers aged 5 to 19 were tested on the McGurk effect (an audio-visual illusion involving speech), the Illusory Flash effect and the Fusion effect (two audio-visual illusions not involving speech) to investigate the development of audio-visual interactions and contrast speech vs. non-speech developmental patterns. Whereas the strength of audio-visual speech illusions varied as a direct function of maturational level, performance on non-speech illusory tasks appeared to be homogeneous across all ages. These data support the existence of independent maturational processes underlying speech and non-speech audio-visual illusory effects.

A Comparison of the Development of Audiovisual Integration in Children with Autism Spectrum Disorders and Typically Developing Children

“…The lack of a linear relationship between chronological age and audiovisual integration in the typically developing children in the current study is not consistent with previous studies that have investigated the development of audiovisual integration, as these studies have demonstrated increased audiovisual integration in older children and adults compared to younger children (Dupont et al, 2005;Hockley & Polka, 1994;Tremblay et al, 2007). There are methodological differences between the current study and previous studies which may underlie these different findings.…”

“…Secondly, previous studies mainly compared groups of children at a particular age to groups of older children or adults, rather than charting development across a wide age range, as was the approach in the current study. Other studies have also used French speakers (Dupont et al, 2005;Tremblay et al, 2007), in contrast to the native English speakers who participated in the current study. Previous research has demonstrated different kinds of…”

“…However, no study adequately takes into account the developmental delay typically found in ASD. Evidence from typically developing children suggests that audiovisual integration (and therefore the size of McGurk effect) increases with age (Dupont, Aubin & Menard, 2005;Tremblay et al, 2007), with one study finding that only 50% of 10-12 year olds tested displayed a McGurk effect equal in size to those of adults tested (Hockley & Polka, 1994). These findings suggest an interesting possibility for autism researchers, as it is possible that evidence of reduced audiovisual integration in speech tasks represent a delay in the development of audiovisual integration in ASD, rather than a deficit that is constant across age.…”

Spatio‐temporal distribution of brain activity associated with audio‐visually congruent and incongruent speech and the McGurk Effect

“…On the other hand, developmental age (5–19 years) of listeners significantly correlated with the number of trials in which the McGurk effect was evident (Trembley et al. 2007), linguistic experience of the listener affected the robustness of the McGurk effect (Sekiyama 1997; Sekyama and Tohkura, 1991) and EEG changes were found to have a predictive value in determining whether the effect will take place (Keil et al. 2012).…”

The development of gaze to a speaking face

“…In their classic paper described above, McGurk and MacDonald (1976) also reported that preschoolers (3-4 yr olds) and school-aged children (7-8 yr olds) are less influenced by visual speech information than are adults (also see Sekiyama and Burnham, 2008). Since then, a number of studies revealed that both visual influence in the context of a McGurk task and speechreading ability (identification of a syllable from visual information only) increases with age (Desjardins et al, 1997;Hockley and Polka, 1994;LaLonde and Frush Holt, 2014;Massaro, 1984;Massaro et al, 1986;Ross et al, 2011;Tremblay et al, 2007). According to this prior work, increased visual influence with development could be due to experience with producing speech sounds (motor experience: Desjardins et al, 1997 report visual influence for children if they can produce the sound that they see on another speaker's face), ongoing perceptual learning/ tuning with respect to visual speech during childhood (ability to pick up phonetic information from the visual signal: Ross et al, 2011;Hockley and Polka, 1994), or that younger children were less attentive to the visual source, leading to an attenuated visual effect (changes in attention to the speaking face: Massaro, 1984).…”