Defining clusters of young autistic and typically developing children based on loudness-dependent auditory electrophysiological responses

Abstract

Background: Autistic individuals exhibit atypical patterns of sensory processing that are known to be related to quality of life, but which are also highly heterogeneous. Previous investigations of this heterogeneity have ordinarily used questionnaires and have rarely investigated sensory processing in typical development (TD) alongside autism spectrum development (ASD). Methods: The present study used hierarchical clustering in a large sample to identify subgroups of young autistic and typically developing children based on the normalized global field power (GFP) of their event-related potentials (ERPs) to auditory stimuli of four different loudness intensities (50, 60, 70, 80 dB SPL): that is, based on an index of the relative strengths of their neural responses across these loudness conditions. Results: Four clusters of participants were defined. Normalized GFP responses to sounds of different intensities differed strongly across clusters. There was considerable overlap in cluster assignments of autistic and typically developing participants, but autistic participants were more likely to display a pattern of relatively linear increases in response strength accompanied by a disproportionately strong response to 70 dB stimuli. Autistic participants displaying this pattern trended towards obtaining higher scores on assessments of cognitive abilities. There was also a trend for typically developing participants to disproportionately fall into a cluster characterized by disproportionately/nonlinearly strong 60 dB responses. Greater auditory distractibility was reported among autistic participants in a cluster characterized by disproportionately strong responses to the loudest (80 dB) sounds, and furthermore, relatively strong responses to loud sounds were correlated with auditory distractibility. This appears to provide evidence of coinciding behavioral and neural sensory atypicalities.

A Multidimensional Investigation of Sensory Processing in Autism: Parent- and Self-Report Questionnaires, Psychophysical Thresholds, and Event-Related Potentials in the Auditory and Somatosensory Modalities

“…While prior studies such as those of Dwyer et al (2020) and Schwartz et al (2020b) have found relationships between auditory ERPs and sensory questionnaire scores, both Dwyer et al (2020) and Schwartz et al (2020b) presented auditory stimuli while participants watched quiet or silent videos of personal interest. Thus, it seems possible that neurophysiological responses to sensory stimuli might track better with the daily sensory experiences of autistic individuals if recorded in an experimental paradigm with multiple stimuli competing for attention, more closely resembling the complex real-world environments on which sensory questionnaire reporting may be based.…”

“…Some prior studies have also examined, in ASD, convergence between questionnaire reports of sensory processing and ERP/ERF responses to auditory stimuli. For example, larger early neural responses to sounds could be related to reports of auditory distractibility or sensory sensitivity ( Karhson and Golob, 2016 ; Dwyer et al, 2020 ). Prior research has also explored associations between questionnaire-reported sensory behaviors and auditory mismatch/P3 responses ( Ludlow et al, 2014 ; Chien et al, 2017 ) as well as ERP indices of auditory habituation ( Hudac et al, 2018 ).…”

“…It appears intuitively reasonable to imagine that questionnaire reports of hyper- or hypo-responsivity to stimuli should be related to neural hyper- and hypo-responsiveness, especially when brain responses are recorded in a context comparable to the busy real world. Indeed, there may be associations between ERPs and sensory questionnaire scores when ERPs are recorded in passive paradigms while background stimuli compete for attention (as in Dwyer et al, 2020 ; Schwartz et al, 2020b ). However, convergence between sensory questionnaire scores and ERP amplitudes has also been observed while participants complete active tasks, requiring maintenance of particular attentional sets, in low-stimulation environments (e.g., Karhson and Golob, 2016 ), and conversely, studies using passive paradigms do not always report clear associations between ERPs and sensory questionnaire scores (e.g., Donkers et al, 2015 ).…”

Exploring Sensory Subgroups in Typical Development and Autism Spectrum Development Using Factor Mixture Modelling

“…EEG data were collected at Time 1 in the APP, when participants were aged 2 through 4 years. The EEG task and processing procedures employed in the present study have been described in greater detail elsewhere (De Meo-Monteil et al, 2019;Dwyer et al, 2020bDwyer et al, , 2021. Briefly, while participants were seated in a caregiver's lap watching a video of their choice, approximately ~ 1200 50 ms complex tones (combining multiple frequencies) of four intensities (50, 60, 70, and 80 dB SPL) were presented binaurally using headphones at a random interstimulus interval of 1-2 s. EEG was sampled at 1000 Hz using a 61-channel electrode cap (easycap.de).…”

“…For example, caregiver-report questionnaires have been criticized on the grounds that caregivers lack direct insight into the internal sensory experiences of autistic people and can therefore only report on external behaviours, which might be misleading (Grandin & Panek, 2014 ). This is concerning, as most studies describing sensory subgroups in autism have relied on caregiver-report questionnaires (see DeBoth & Reynolds, 2017 ), with exceptions including a study based on a self-report questionnaire (Elwin et al, 2017 ) and one based primarily on auditory event-related potentials (ERPs; Dwyer et al, 2020b ).…”