Showing papers by "Gert Pfurtscheller published in 1996"
TL;DR: In this article, an enhancement of mu rhythms in the primary hand area during visual processing or during foot movement was observed. But the hand area is not needed for visual processing, nor is it needed for preparation for foot movement.
1,030 citations
TL;DR: Post-movement beta (around 20 Hz) synchronization was investigated in 2 experiments with self-paced finger extension and flexion and externally paced wrist movement and is interpreted as a correlate of "idling" motor cortex neurons.
651 citations
TL;DR: The results suggest that the dynamics of premovement desynchronisation and postmovement synchronisation of central beta-rhythms is related to hand dominance.
243 citations
TL;DR: A simple approach to calculating time courses of coherence for data recorded during an event-related paradigm was demonstrated and it was demonstrated that ERCoh can provide information regarding the dynamic interaction of spatially separated brain regions.
217 citations
TL;DR: The prototype Graz BCI II, which is based on the distinction of three different types of EEG pattern, is described, and results of online and offline classification performance of four subjects are reported.
Abstract: The paper describes work on the brain-computer interface (BCI). The BCI is designed to help patients with severe motor impairment (e.g. amyotropic lateral sclerosis) to communicate with their environment through wilful modification of their EEG. To establish such a communication channel, two major prerequisites have to be fulfilled: features that reliably describe several distinctive brain states have to be available, and these features must be classified on-line, i.e. on a single-trial basis. The prototype Graz BCI II, which is based on the distinction of three different types of EEG pattern, is described, and results of online and offline classification performance of four subjects are reported. The online results suggest that, in the best case, a classification accuracy of about 60% is reached after only three training sessions. The offline results show how selection of specific frequency bands influences the classification performance in singletrial data.
145 citations
Journal Article•
143 citations
TL;DR: Comparison of left and right foot movement revealed a larger post-movement beta synchronization (PMBS) with left foot movement, but no differences concerning the topographical distribution of the PMBS.
133 citations
TL;DR: Results show that in general movement specific EEG-patterns can be found, classified in real time and used to move a cursor on a monitor to the left or right.
120 citations
TL;DR: It is demonstrated that hand dominance, handedness and type of movement influence the proportion of pre-movement mu-rhythm desynchronisation in the left and right peri-rolandic area.
87 citations
TL;DR: An extended version of Kohonen's LVQ algorithm, called Distinction Sensitive Learning Vector Quantization (DSLVQ), is introduced which overcomes a major problem of LVQ, the dependency on proper pre-processing methods for scaling and feature selection.
87 citations
Journal Article•
TL;DR: The results suggest that both amplitude and duration of the extensor muscle contraction are encoded in the time course of mu-rhythm desynchronization.
TL;DR: In this paper, the authors analyzed whether type of movement (brisk vs slow) and active muscle force are encoded in the time course of mu-rhythm desynchronization during self-paced finger movements.
Abstract: WE analysed whether type of movement (brisk vs slow) and active muscle force are encoded in the time course of mu-rhythm desynchronization during self-paced finger movements. Ten subjects performed 100 brisk and slow extensions of the right index finger. The time course of mu-rhythm desynchronization in the contralateral sensorimotor area before movement was identical for both types of movements. Brisk movements accompanied by a stronger extensor muscle contraction were preceded by larger desynchronization. The onset of mu-rhythm recovery was related to the duration of the extensor EMG burst in both types of movement. The results suggest that both amplitude and duration of the extensor muscle contraction are encoded in the time course of mu-rhythm desynchronization.
TL;DR: It is concluded that the coherence increase seen with nose, reference data is due to an indirecteeffect of mu rhythm desynchronisation, rather than any increase in synchrony of the mu rhythms themselves.
Abstract: The impact is reported of different EEG derivation types on short-term changes in the inter-hemispheric coherence between the left and right sensorimotor areas, during the planning and execution of right index finger movements. Data are recorded during an event-related paradigm in which cued index finger movements are made. Event-related coherence analysis is then applied to the monopolar (nose reference) data, as well as source derivation. The results show that inter-hemispheric coherence between sensorimotor areas is dependent on the EEG derivation type. An increase in coherence during movement is found with nose reference and bipolar data, whereas for local average reference and source derivations, low inter-hemispheric coherence is observed, with no change in the coherence during movement. It is concluded that the coherence increase seen with nose, reference data is due to an indirecteeffect of mu rhythm desynchronisation, rather than any increase in synchrony of the mu rhythms themselves. Local average reference and source derivations better reflect the activity of the underlying cortical structures (the mu generating networks), and coherence analysis using these derivations shows that the mu rhythms of left and right hemispheres are not coherent.
TL;DR: The system TBNN (Tree-Based Neural Network) uses a decision-tree generator to provide knowledge that defines the architecture of a backpropagation neural network, including feature selection and initialisation of the weights.
TL;DR: Brainstem auditory evoked potentials in patients with respiratory insufficiency resulting from severe inflammatory encephalopathies showed prolonged interpeak latencies and delayed absolute latencies of waves I, II, III, and V and the electrophysiologic abnormalities of wave III and the IV/V complex may be a reflection of the disturbed central control of ventilation.
Abstract: Brainstem auditory evoked potentials (BAEPs) were recorded in 14 artificially ventilated patients (12 males, 2 females; mean age 33.3 ± 16.3 years, range 18-67) with respiratory insufficiency resulting from severe inflammatory encephalopathies. The results were compared with those of 17 healthy volunteers (13 males, 4 females; mean age 27.4 ± 5.3 years, range 21-45). BAEPs in the study patients showed prolonged interpeak latencies (I-III. I-V, III-V, IV-V) and delayed absolute latencies of waves I, II, III and V at least on one side. Because the auditory pathways are in the near vicinity of the respiratory control centers in the brainstem, the electrophysiologic abnormalities of wave III and the IV/V complex may be a reflection of disturbed central control of ventilation.