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Individuals with developmental dyslexia have been characterized by problems with attentional orienting. In the current study, we specifically focused on possible changes in endogenous visual orienting that may be reflected in the electroencephalogram. A variant of the Posner cuing paradigm was employed with valid or invalid central cues that preceded target stimuli that were presented in the left or right visual field. The target stimuli consisted of vertical or horizontal stripes with low (two thick lines) or high (six thin lines) spatial frequencies. We examined lateralized alpha power in the cue-target interval as recent studies revealed that a contra vs. ipsilateral reduction in alpha power relates to the orienting of attention. An initial orienting effect in the lower alpha band was more pronounced for dyslexic individuals than for controls, suggesting that they oriented at an earlier moment in time. However, in contrast with controls, at the end of the cue-target interval no clear contralateral reduction in the upper alpha band was observed for dyslexic individuals. Dyslexic individuals additionally displayed slower responses, especially for invalidly cued high spatial frequency targets in the left visual field. The current data support the view that dyslexic individuals orient well to the cued location but have a problem with sustaining their attention., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

The authors investigated whether participants with dyslexia had problems with executing discrete keying sequences and with switching between chunks in those sequences. Participants with dyslexia and participants in the control group executed 2 6-key sequences each, with 1 sequence consisting of 2 successive instances of 1 3-key segment (2 x 3 sequence) and the other not involving such a repetition (1 x 6 sequence). The authors assumed that during execution of the 2 x 3 sequence, the same chunk could be reused, whereas during execution of the 1 x 6 sequence a switch between chunks had to be made. Participants with dyslexia were slower than participants in the control group in executing the 1 x 6 sequence, but not the 2 x 3 sequence. The authors suggest that the smaller amount of repetitions of the chunks in the 1 x 6 sequence or the increased difficulty of the 1 x 6 sequence led to the slowed execution of the 1 x 6 sequence in participants with dyslexia.