Thanks to the @dfg_public and all involved for funding a new 630 K€ joint research endeavour of @GesaHartwigsen and @ObleserLab: “The impact of domain-general networks on natural language processing”. Postdoc and PhD trainee op’s upcoming at @MPI_CBS and @UniLuebeck soon.
— Jonas Obleser (@jonasobleser) June 2, 2021
New PhD opportunity: @bjoherrmann (Rotman Research) and @ObleserLab at @UniLuebeck, Germany, have a @dfg_public-funded 3‑year PhD position! (neural dynamics, temporal expectation, ageing). Apply now until July 12! Please RT widely/alert your MSc/RAs. https://t.co/gphGf8Xx4c pic.twitter.com/GneEmTGvaP
— Jonas Obleser (@jonasobleser) June 26, 2020
Wöstmann, Alavash and Obleser demonstrate that alpha oscillations in the human brain implement distractor suppression independent of target selection.
In theory, the ability to selectively focus on relevant objects in our environment bases on selection of targets and suppression of distraction. As it is unclear whether target selection and distractor suppression are independent, we designed an Electroencephalography (EEG) study to directly contrast these two processes.
Participants performed a pitch discrimination task on a tone sequence presented at one loudspeaker location while a distracting tone sequence was presented at another location. When the distractor was fixed in the front, attention to upcoming targets on the left versus right side induced hemispheric lateralisation of alpha power with relatively higher power ipsi- versus contralateral to the side of attention.
Critically, when the target was fixed in front, suppression of upcoming distractors reversed the pattern of alpha lateralisation, that is, alpha power increased contralateral to the distractor and decreased ipsilaterally. Since the two lateralized alpha responses were uncorrelated across participants, they can be considered largely independent cognitive mechanisms.
This was further supported by the fact that alpha lateralisation in response to distractor suppression originated in more anterior, frontal cortical regions compared with target selection (see figure).
The paper is also available as preprint here.
Congratulations to our currently ERC-funded lab member and postdoc Mohsen Alavash who has just secured 3‑year funding (~380,000 €) by the Deutsche Forschungsgemeinschaft (DFG) for an ambitious project: Mohsen wants to get closer to a network/graph-theoretical description of how spatial attention in the listening brain is organised. In a later stage of the project, Mohsen also plans on studying how the network organisation of spatial attention may be altered in hearing-impaired listeners.
We are glad that Mohsen plans on running this project within the Obleser lab, here at the University of Lübeck.
Also, make sure to check out Mohsen’s latest publication on the topic.
Im Februar hatte ich die Ehre, für die Kind Hörstiftung auf deren 2019er Symposium in Berlin unsere Arbeiten zur Vorhersage des Hörerfolgs exemplarisch anhand einiger unserer Studien allgemeinverständlich zu beleuchten. Ein 25-minütiges Video dieses Vortrags ist jetzt online.
(In February, I had the honour of presenting some of our recent work on predicting individuals’ listening success at the symposium of the Kind Hearing Foundation. A video in German is now available.)
In this three-year project, we will use the auditory modality as a test case to investigate how the suppression of distracting information (i.e., “filtering”) is neurally implemented. While it is known that the attentional sampling of targets (a) is rhythmic, (b) can be entrained, and © is modulated by top-down predictions, the existence and neural implementation of these mechanisms for the suppression of distractors is at present unclear. To test this, we will use adaptations of established behavioural paradigms of distractor suppression and recordings of human electrophysiological signals in the Magento-/ Electroencephalogram (M/EEG).
Wöstmann, Schmitt and Obleser demonstrate that closing the eyes enhances the attentional modulation of neural alpha power but does not affect behavioural performance in two listening tasks
Does closing the eyes enhance our ability to listen attentively? In fact, many of us tend to close their eyes when listening conditions become challenging, for example on the phone. It is thus surprising that there is no published work on the behavioural or neural consequences of closing the eyes during attentive listening. In the present study, we demonstrate that eye closure does not only increase the overall level of absolute alpha power but also the degree to which auditory attention modulates alpha power over time in synchrony with attending to versus ignoring speech. However, our behavioural results provide evidence for the absence of any difference in listening performance with closed versus open eyes. The likely reason for this is that the impact of eye closure on neural oscillatory dynamics does not match alpha power modulations associated with listening performance precisely enough (see figure).
The paper is available as preprint here.
How brain areas communicate shapes human communication: The hearing regions in your brain form new alliances as you try to listen at the cocktail party
Obleserlab Postdocs Mohsen Alavash and Sarah Tune rock out an intricate graph-theoretical account of modular reconfigurations in challenging listening situations, and how these predict individuals’ listening success.