Neural correlates of sequence learning in children with developmental dyslexia

Abstract

Developmental Dyslexia (DD) is a condition in which reading accuracy and/or fluency falls substantially below what is expected based on the individuals age, general level of cognitive ability, and educational opportunities. The procedural circuit deficit hypothesis (PDH) proposes that DD may be largely explained in terms of alterations of the cortico‐basal ganglia procedural memory system (in particular of the striatum) whereas the (hippocampus‐dependent) declarative memory system is intact, and may serve a compensatory role in the condition. The present study was designed to test this hypothesis. Using Magnetic Resonance Imaging, we examined the functional and structural brain correlates of sequence‐specific procedural learning (SL) on the serial reaction time task, in 17 children with DD and 18 typically developing (TD) children. The study was performed over 2 days with a 24‐h interval between sessions. In line with the PDH, the DD group showed less activation of the striatum during the processing of sequential statistical regularities. These alterations predicted the amount of SL at day 2, which in turn explained variance in children's reading fluency. Additionally, reduced hippocampal activation predicted larger SL gains between day 1 and day 2 in the TD group, but not in the DD group. At the structural level, caudate nucleus volume predicted the amount of acquired SL at day 2 in the TD group, but not in the DD group. The findings encourage further research into factors that promote learning in children with DD, including through compensatory mechanisms.

The Influence of Word Length and Presentation Directions on Information Encoding and Brain Cell Activity in the Memory Systems of Gifted Students through ERP Technology

“…This implies that the structural encoding processes in short-term memory are rapid when stimuli comprise a smaller group of component letters. Consequently, as the number of letters in words increases, the process of structural encoding slows down (Hedenius & Persson, 2022). These ndings align with the results of Mohamed's (2014) study and Li (2018) study, which investigated the structural encoding processes of words and non-words.…”

Impaired and Spared Auditory Category Learning in Developmental Dyslexia

“…But domain-general accounts assert that dyslexia is a consequence of a selective dysfunction in procedural learning and memory (Nicolson & Fawcett, 2011Ullman et al, 2020;Ullman & Pullman, 2015), which provides a mechanistic account for the diverse range of nonphonological linguistic and nonlinguistic symptoms observed in dyslexia (Beach et al, 2022;Gabay, 2021;Gabay et al, 2012Hedenius et al, 2021;Howard et al, 2006;Lum et al, 2013;Massarwe et al, 2022;Pavlidou et al, 2009Pavlidou et al, , 2010Sperling et al, 2004;Stoodley et al, 2006;Vicari et al, 2003Vicari et al, , 2005. Individuals with dyslexia demonstrate structural and functional differences in core structures of the procedural memory systems, including the cerebellum (Alvarez & Fiez, 2018) and basal ganglia (Brunswick et al, 1999;Hedenius & Persson, 2022;Kita et al, 2013;Wang et al, 2019), providing further evidence for a general procedural learning and memory deficit.…”

Academic achievements and brain volume development in children and adolescents

“…The striatum is involved in incentive processes, motivation, and behavioral control ( Delgado 2007 ; Somerville and Casey 2010 ). Procedural sequence learning in children is associated with striatal volume ( Hedenius and Persson 2022 ). Striatal volumes peak at 10–12 years of age and reduce at adolescence ( Narvacan et al.…”