Speech cortical activation and connectivity in typically developing children and those with listening difficulties

Abstract

Listening difficulties (LiD) are a widespread but poorly understood form of hearing impairment in people who have normal audiometry. Recent research suggests that childhood LiD are cognitive rather than auditory in origin. We assessed that hypothesis using behavioral testing and fMRI with 43 typically developing children and 42 children with LiD, categorized by caregiver report. The children with LiD had clinically normal hearing. For sentence listening tasks, we found no group differences in fMRI brain cortical activation by increasingly complex speech, from phonology to intelligibility to semantics. Using unstimulated fMRI connectivity analysis, we examined how cortical auditory and related speech perception networks interact. Group differences were found only in cortical connections engaged by more complex speech processing. Strength of the affected connections was related to the children's performance on tests of dichotic listening, speech-in-noise, attention, memory and verbal vocabulary. Childhood LiD thus reflects cognitive and language rather than auditory deficits.

Altered brain network topology in children with Auditory Processing Disorder: a resting-state multi-echo fMRI study

“…Children with APD had increased functional connectivity in the left inferior frontal gyrus (Broca’s area) and left posterior middle temporal gyrus; these regions are implicated in language production and comprehension and lexical and semantic processes (Hagoort, 2014; Acheson et al, 2013; Hickok & Poeppel, 2004). Stewart and colleagues (2021) also reported that in the Semantics network, children with APD had stronger functional connectivity in the right parahippocampal gyrus compared to auditory areas such as left Heschl’s gyrus, left middle temporal gyrus (MTG), right superior temporal gyrus (STG), and right planum temporale. Still, they had weaker connections in the left temporal fusiform cortex and right superior temporal gyrus (Stewart et al, 2021).…”

“…Stewart and colleagues (2021) also reported that in the Semantics network, children with APD had stronger functional connectivity in the right parahippocampal gyrus compared to auditory areas such as left Heschl’s gyrus, left middle temporal gyrus (MTG), right superior temporal gyrus (STG), and right planum temporale. Still, they had weaker connections in the left temporal fusiform cortex and right superior temporal gyrus (Stewart et al, 2021). Stewart et al (2021) concluded that atypical neurological aspects of APD are connected with language comprehension, consistent with the high rate of language disorder comorbidity in children with APD (Sharma et al, 2009; Dawes & Bishop, 2010; Barker et al, 2017).…”

“…Hence, the complex interactions between cognitive, language, reading, and auditory processing abilities in the brain of children with APD are not entirely understood. The potential for neuroimaging research to address this controversy and help understand of the top-down processing mechanisms in children with APD has been increasingly recognized (Moore & Hunter, 2013; Bartel-Friedrich et al, 2010; AAA, 2010; Pluta et al, 2014; Stewart et al, 2021).…”

“…Using rsfMRI data, functional connectivity can be estimated between anatomically distributed regions by recording temporal correlations of spontaneous fluctuations in the Blood-Oxygenation-Level-Dependent (BOLD) signal (Biswal et al, 1997). In the APD literature, to our knowledge, there have been only three resting-state fMRI studies that investigated this intrinsic activity (Pluta et al 2014; Stewart et al, 2021, Preprint; Hoyda et al, 2021, Preprint). The earliest of these studies investigated 13 children with diagnosed APD (without other neurological signs) and 15 healthy control (HC) children (Pluta et al, 2014) using regional homogeneity (ReHo) to investigate changes in the pattern of the default mode network (DMN).…”

“…Pluta et al (2014) argued that modality-specific perceptual dysfunction could not differentiate between children with neurodevelopmental APD and those with attention deficits. More recent research involving 81 children (n=42 Listening difficulties/APD; n=39 typically developing/TD) used a region of interest (ROIs) approach to assess how speech perception and listening networks (Phonology, Intelligibility, Semantics) are different in children with APD compared to TD (Stewart et al, 2021). Stewart and colleagues (2021).…”