Do developmental dyslexia and congenital amusia share underlying impairments?

Abstract

Developmental dyslexia and congenital amusia have common characteristics. Yet, their possible association in some individuals has been addressed only scarcely. Recently, two converging studies reported a sizable comorbidity rate between these two neurodevelopmental disorders (Couvignou et al., Cognitive Neuropsychology 2019; Couvignou & Kolinsky, Neuropsychologia 2021). However, the reason for their association remains unclear. Here, we investigate the hypothesis of shared underlying impairments between dyslexia and amusia. Fifteen dyslexic children with amusia (DYS+A), 15 dyslexic children without amusia (DYS-A), and two groups of 25 typically developing children matched on either chronological age (CA) or reading level (RL) were assessed with a behavioral battery aiming to investigate phonological and pitch processing capacities at auditory memory, perceptual awareness, and attentional levels. Overall, our results suggest that poor auditory serial-order memory increases susceptibility to comorbidity between dyslexia and amusia and may play a role in the development of the comorbid phenotype. In contrast, the impairments observed in the DYS+A children for auditory item memory, perceptual awareness, and attention might be a consequence of their reduced reading experience combined with weaker musical skills. Comparing DYS+A and DYS-A children suggests that the latter are more resourceful and/or have more e ective compensatory strategies, or that their phenotype results from a di erent developmental trajectory. We will discuss the relevance of these ndings for delving into the etiology of these two developmental disorders and address their implications for future research and practice.

Role of the prefrontal cortex in musical and verbal short-term memory: A functional near-infrared spectroscopy study

“…Overall, these previous studies and the current findings highlight the potential of fNIRS as a suitable neuroimaging technique to explore functional differences between children with DLD and TD children, and suggest that variations of cerebral activity in response to memory load manipulation could be an adequate neurophysiological marker. Future studies could investigate further the engagement of lateral frontal regions during auditory STM for musical and verbal material in children with DLD as deficits in STM for both materials have been observed (Couvignou et al, 2023; Couvignou & Kolinsky, 2021; Forgeard et al, 2008; Ziegler et al, 2012). In the long term, a better understanding of the neural mechanisms underlying auditory STM in DLD and their link to the processes reported to be impaired in this population (e.g., syntax processing, phoneme discrimination, etc.)…”

“…Impairment of verbal STM has been shown to be a hallmark of language-related learning disorders, such as dyslexia (Majerus & Cowan, 2016;Roodenrys & Stokes, 2001;Ziegler et al, 2009Ziegler et al, , 2011 and Developmental Language Disorder (DLD, Archibald & Gathercole, 2006;Nickisch & Von Kries, 2009;Nithart et al, 2009). A few studies have also observed impairment for musical STM in dyslexic children (Couvignou et al, 2023;Forgeard et al, 2008;Ziegler et al, 2012). Moreover, recent studies have shown a sizeable comorbidity (~30%) between dyslexia and congenital amusia (in both adults: Couvignou et al, 2019, andchildren: Couvignou &Kolinsky, 2021;Couvignou et al, 2023).…”

“…A few studies have also observed impairment for musical STM in dyslexic children (Couvignou et al, 2023;Forgeard et al, 2008;Ziegler et al, 2012). Moreover, recent studies have shown a sizeable comorbidity (~30%) between dyslexia and congenital amusia (in both adults: Couvignou et al, 2019, andchildren: Couvignou &Kolinsky, 2021;Couvignou et al, 2023). Congenital amusia is a lifelong disorder characterized by a specific impairment in musical STM (for reviews, see Peretz, 2016;Tillmann et al, 2015Tillmann et al, , 2023.…”

Explicit processing of melodic structure in congenital amusia can be improved by redescription-associate learning

“…Considering that the redescription-associate learning paradigm focused on the dissociation between implicit and explicit processes, it may have clinical implications beyond amusia. As a neurodevelopmental disorder, amusia is akin to other neurodevelopmental disorders such as developmental dyslexia with impairment in reading and congenital prosopagnosia with impairment in face recognition (Couvignou & Kolinsky, 2021;Couvignou et al, 2019Couvignou et al, , 2023Mignault Goulet et al, 2012;Peretz, 2016). Specifically, dyslexics or prosopagnosics exhibit intact implicit but impaired explicit processing of phonemes (Bonte & Blomert, 2004;McPherson et al, 1998;Mundy & Carroll, 2012) or faces (Eimer et al, 2012;Rivolta et al, 2012;Stumps et al, 2020) respectively.…”