Steady-State movement related potentials for brain–computer interfacing

An approach for brain-computer interfacing (BCI) by analysis of steady-state movement related potentials (ssMRPs) produced during rhythmic finger movements is proposed in this paper. The neurological background of ssMRPs is briefly reviewed. Averaged ssMRPs represent the development of a lateralized rhythmic potential, and the energy of the EEG signals at the finger tapping frequency can be used for single-trial ssMRP classification. The proposed ssMRP-based BCI approach is tested using the classic Fisher's linear discriminant classifier. Moreover, the influence of the current source density transform on the performance of BCI system is investigated. The averaged correct classification rates (CCRs) as well as averaged information transfer rates (ITRs) for different sliding time windows are reported. Reliable single-trial classification rates of 88%-100% accuracy are achievable at relatively high ITRs. Furthermore, we have been able to achieve CCRs of up to 93% in classification of the ssMRPs recorded during imagined rhythmic finger movements. The merit of this approach is in the application of rhythmic cues for BCI, the relatively simple recording setup, and straightforward computations that make the real-time implementations plausible

De Nederlandse letterkunde als wereldliteratuur

Moderne Nederlandse koloniale en postkoloniale literatuu

Lateralized electrical brain activity reveals covert attention allocation during speaking

Acknowledgements We thank Svetlana Gerakaki for providing us with the pictures of objects with a canonical orientation and Sophie Kirkels and Annelies van Wijngaarden for assistance with editing the pictures.Peer reviewedPostprin

'Ik begrijp van dat leven werkelijk niets', Gerard Reve in Indonesië

Modern and Contemporary Studie

De Nederlandse letterkunde als provinciale literatuur

Rede uitgesproken door Prof.dr. Olf Praamstra bij zijn afscheid als bijzonder hoogleraar Nederlandse Literatuur in Contact met Andere Culturen aan de Universiteit Leiden op vrijdag 12 juni 2015FGW-tijdelij

De Indische jaren van Gerard Reve

Modern and Contemporary Studie

Cognitive-behavioural intervention for depression after stroke: Five single case studies on effects and feasibility

The purpose of the study was to investigate whether or not a cognitive-behavioural intervention for depression after stroke has an effect and is feasible. A single-subject quasi experimental design (SSED) was used with an AB design and follow-up. The participants were five first episode stroke patients attending outpatient rehabilitation in a rehabilitation centre in The Netherlands. Mood and quality of life were measured on four occasions over four weeks (baseline phase A). During the eight week intervention phase (B) a visual analogue measure of mood was administered three times a week. Immediately after the intervention, and one and three months later, the baseline measures were repeated. The intervention (phase B) was based on cognitive-behavioural principles: recognising negative thoughts and challenging them, learning principles of relaxation, and planning of pleasurable activities. Following intervention three patients reported they had improved, three patients reported a minor improvement in quality of life, and four patients reported a more positive mood. Three months later three patients reported fewer depressive symptoms. Both patients and therapist were positive about the intervention and three months later, in daily life, all patients still applied the strategies. It was concluded that despite some ambiguous results, it seems that the cognitive-behavioural intervention has an effect on patients' mood. The intervention was rated as feasible by both patients and therapists

An MEG Study of Picture Naming

The purpose of this study was to relate a psycholinguistic processing model of picture naming to the dynamics of cortical activation during picture naming. The activation was recorded from eight Dutch subjects with a whole-head neuromagnetometer. The processing model, based on extensive naming latency studies, is a stage model. In preparing a picture's name, the speaker performs a chain of specific operations. They are, in this order, computing the visual percept, activating an appropriate lexical concept, selecting the target word from the mental lexicon, phonological encoding, phonetic encoding, and initiation of articulation. The time windows for each of these operations are reasonably well known and could be related to the peak activity of dipole sources in the individual magnetic response patterns. The analyses showed a clear progression over these time windows from early occipital activation, via parietal and temporal to frontal activation. The major specific findings were that (1) a region in the left posterior temporal lobe, agreeing with the location of Wernicke's area, showed prominent activation starting about 200 msec after picture onset and peaking at about 350 msec, (i.e., within the stage of phonological encoding), and (2) a consistent activation was found in the right parietal cortex, peaking at about 230 msec after picture onset, thus preceding and partly overlapping with the left temporal response. An interpretation in terms of the management of visual attention is proposed.Peer reviewe