Birgit Griesmayr

Learn More
Neural correlates of control mechanisms in human working memory are discussed at two levels in this review: (i) at 'item level', where in multi-item working memory information needs to be organized into sequential memory representations, and (ii) at a 'process level', indicating the integration and control of a variety of cognitive functions involved in(More)
The involvement of oscillatory activity, especially at theta and gamma frequency, in human working memory has been reported frequently. A salient pattern during working memory is electroencephalographic frontal midline theta activity which has been suggested to reflect monitoring functions in order to deal with a task. In general, theta activity has been(More)
In healthy humans, it has been shown that executive functions are associated with increased frontal-midline EEG theta activity and theta phase coupling between frontal and posterior brain regions. In individuals with schizophrenia, central executive functions are supposed to be heavily impaired. Given that theta phase coupling is causally involved in(More)
It has been claimed that the coordination of neuronal oscillations differing in frequency is relevant for cognition. However, the validity of this claim has scarcely been investigated. Recent studies revealed that cross-frequency phase coupling and modulations of alpha-power dissociate between retention of relevant and suppression of irrelevant information(More)
In the present study, we investigate the role of upper alpha oscillations for semantic access and retrieval processes. In each of a series of trials, subjects were presented trains of distorted pictures (with decreasing levels of degradation), and were asked to respond as quickly as possible when they recognize the meaning of the picture. The results show(More)
The present study attempts to demonstrate functional similarities between the P1 component of event-related potentials and alpha oscillations that are predicted by the 'alpha inhibition-timing' hypothesis. On the basis of findings showing that the frequency characteristic of the P1 component lies in the alpha range and that alpha oscillation is functionally(More)
We tested the hypothesis whether images of real objects elicit stronger gamma (>25 Hz) synchronization, when compared with scrambled objects. The background of this study is a recent debate about the functional meaning of evoked and induced gamma oscillations. Brain electrical source analysis (BESA) and low resolution electromagnetic tomography analysis(More)
Working Memory and executive functioning deficits are core characteristics of patients suffering from schizophrenia. Electrophysiological research indicates that altered patterns of neural oscillatory mechanisms underpinning executive functioning are associated with the psychiatric disorder. Such brain oscillatory changes have been found in local amplitude(More)
The aim of the present electroencephalographic (EEG) study was to investigate neuronal correlates of working memory encoding in a visuo-spatial serial delayed match-to-sample task. A rapid serial visual presentation approach was used to dissociate brain activity related to encoding of visuo-spatial targets and cortical activity evoked by suppression of(More)
  • 1