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Mindfulness based stress reduction (MBSR) training has been proposed to improve attentional skills by modulating thalamo-cortical loops that affect the sensitivity of relevant cortical areas like the somatosensory cortex. This modulation may be reflected in the electroencephalographic (EEG) alpha rhythm, and could affect the processing of subsequently applied intracutaneous electrical stimuli. Participants took part in an MBSR training and participated in two EEG sessions. EEG was measured in variants of an endogenous orienting paradigm in which attention had to be directed to the left or right forearm. After the orienting interval, the electrical stimulus was applied, equally likely on the attended or the unattended forearm. One group of participants took part in the EEG session before and after the training, while the other group took part after the training, and another time, eight weeks later. The influence of the MBSR training and spatial attention were examined with behavioral measures, lateralized alpha power within the orienting interval, and with event-related potentials (ERPs) evoked by the electrical stimuli. Self-reported mindfulness was clearly affected by the training, but no influence was found on other behavioral measures. Alpha power was clearly lateralized due to spatial attention and several ERP components (N130, N180, P340) were modulated by spatial attention but no support was found for an influence of the MBSR training. Finally, analyses revealed that individual differences in training time modulated some of the observed effects, but no support was found for an influence on attentional orienting. [ABSTRACT FROM AUTHOR]

Various studies suggest that movement sequences are initially learned predominantly in effector-independent spatial coordinates and only after extended practice in effector-dependent coordinates. The present study examined this notion for the discrete sequence production (DSP) task by manipulating the hand used and the position of the hand relative to the body. During sequence learning in Experiment 1, in which sequences were executed by reacting to key-specific cues, hand position appeared important for execution with the practiced but not with the unpracticed hand. In Experiment 2 entire sequences were executed by reacting to one cue. This produced similar results as in Experiment 1. These experiments support the notion that robustness of sequencing skill is based on several codes, one being a representation that is both effector and position dependent. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]