Event-related potentials to tones show differences between children with multiple risk factors for dyslexia and control children before the onset of formal reading instruction

Abstract

Event-related potentials to tones show differences between children with multiple risk factors for dyslexia and control children before the onset of formal reading instruction Hämäläinen, Jarmo; Lohvansuu, Kaisa; Ervast, Leena; Leppänen, Paavo H.T.Hämäläinen, J., Lohvansuu, K., Ervast, L., & Leppänen, P. (2015). Event-related potentials to tones show differences between children with multiple risk factors for dyslexia and control children before the onset of formal reading instruction. AbstractMultiple risk factors can affect the development of specific reading problems or dyslexia. In addition to the most prevalent and studied risk factor, phonological processing, also auditory discrimination problems have been found in children and adults with reading difficulties. The present study examined 37 children between the ages of 5 and 6, 11 of which had multiple risk factors for developing reading problems. The children participated in a passive oddball EEG experiment with sinusoidal sounds with changes in sound frequency, duration, or intensity. The responses to the standard stimuli showed a negative voltage shift in children at risk for reading problems compared to control children at 107-215 ms in frontocentral areas corresponding to P1 offset and N250 onset. Source analyses showed that the difference originated from the left and right auditory cortices. Additionally, the children at risk for reading problems had a larger late discriminative negativity (LDN) response in amplitude for sound frequency change than the control children. The amplitudes at the P1-N250 time window showed correlations to letter knowledge and phonological identification whereas the amplitudes at the LDN time window correlated with verbal short-term memory and rapid naming. These results support the view that problems in basic auditory processing abilities precede the onset of reading instruction and can act as one of the risk factors for dyslexia.

Temporal dynamics of early visual word processing – Early versus late N1 sensitivity in children and adults

“…As modern high-input impedance amplifiers and their accurate digital filters for power noise provide excellent EEG signal collection even with higher electrode impedances (Ferree et al, 2001), the electrode impedance was kept below 50 k. This impedance threshold has been widely used in previous studies using EGI systems across a variety of EEG labs (e.g., Franklin et al, 2007;Hämäläinen et al, 2015;Maurer et al, 2005b;Rihs, Michel, & Thut, 2007). Raw data was preprocessed using BESA software.…”

Cortical Auditory-Evoked Potential and Behavioral Evidence for Differences in Auditory Processing between Good and Poor Readers

“…This includes difficulties in oral language and reading (Schulte-Körne et al, 1998;Molfese, 2000;Sharma et al, 2009;Boets et al, 2011). The effects of poor AP can be evident even before formal reading instruction begins and can be a risk factor for reading disability in young children (Lovio et al, 2010;Hämäläinen et al, 2015). The contribution of AP to reading success is supported by evidence that assistive listening devices that improve acoustic signals enhance reading in children with dyslexia (Hornickel et al, 2012).…”

The First 250 ms of Auditory Processing: No Evidence of Early Processing Negativity in the Go/NoGo Task

“…These observations, and the present findings, strongly support a link between N1c and stimulus-response processing, at least in paradigms that require a response. Moreover, the clarification of those effects could provide useful insight for researchers using the T-complex to study auditory perception or deficits in individuals with learning difficulties (e.g., dyslexia) [71][72][73] .…”