Children with Pervasive Developmental Disorders (PDD), such as children with autism spectrum disorders (ASD), autism, Asperger's syndrome, or Pervasive Developmental Disorder - Not Otherwise Specified, demonstrate some level of impairment in the social and communicative use of language, social interactions, and imaginative and symbolic play, with an onset prior to the age of 3 years [1–3]. Some children with ASD have difficulties processing speech in background noise [4, 5]. To this effect, emerging evidence suggests that the neural encoding of speech sounds may be impaired in these children [6–11]. Some children with ASD exhibit auditory brainstem processing deficits specific to speech stimuli [9, 10], such as deficits in neural synchrony (timing) and phase locking (periodicity encoding; transcription of pitch contour), as well as degradation of the morphology of the responses in quiet and background noise, despite normal click-evoked brainstem responses. Reduced amplitude, delayed timing, and overall degraded morphology of cortical responses to speech syllables have also been reported in children with ASD relative to typically-developing (TD) children [6–8, 11, 12].
Several interventions targeting language, social skills, and auditory processing have been implemented for children with ASD (e.g., [13–18], see also the National Autism Center's National Standards Project report ). Given the variable nature of ASD, it is not surprising that treatment options and success vary across individuals. Thus, although studies show promise of success, further research is still needed to distinguish appropriate interventions for a specific child.
Fast ForWord Language (FFW; Scientific Learning Corp.; composed of Fast ForWord Language and Language to Reading) is a commercially available language training program consisting of seven games focusing on perceptual discrimination and language comprehension. The program provides auditory-focused training, including lessons in listening and sound sequencing, auditory attention, auditory discrimination, phoneme discrimination, and memory. Game sounds are spectrally and temporally altered to enhance cues important for speech discrimination and these enhancements are gradually reduced as a child progresses through the game. Games are completed when the child reaches an accuracy criterion (85%), which eventually leads to the advancement from the Language to the Language to Reading program. A retrospective study of 100 children with ASD who used FFW Language along with their regular intervention program showed that almost every child who completed training showed improvements in receptive and expressive language .While this study suggests that FFW training can benefit children with ASD with respect to language learning, objective neural indices of auditory function were not assessed and the impact of FFW on biological functions in children with ASD were not known.
This study evaluated the effectiveness of FFW for strengthening central auditory processing of speech sounds presented in quiet and background noise conditions in high-functioning children with ASD. Given the evidence from the retrospective study of children with ASD , in conjunction with the reports of improvements in central auditory processing after auditory training in both the brainstem [21–24] and cortex [21, 22, 25–28], and considering the auditory-based training components of FFW, we hypothesized that FFW training modifies the neural processing of sound in children with ASD. We predicted that children who completed FFW exercises would show improvement in the neural encoding of speech syllables, including faster response timing, greater fidelity of the response relative to the stimulus, and more accurate pitch encoding over time. Here we present case studies of the biological impact of FFW in five children with ASD.