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Tag: Strauß

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EEG / MEG Neural Oscillations Neural Phase Papers Publications

Strauß again — in Jour­nal of Neuroscience

Alum­na Dr. Antje Strauß just got anoth­er paper on:

Alpha Phase Deter­mines Suc­cess­ful Lex­i­cal Deci­sion in Noise

by Antje Strauß, Mol­ly Hen­ry, Math­ias Scharinger, and Jonas Obleser

appeared in Jour­nal of Neu­ro­science. Check the abstract below;

Abstract
Psy­chophys­i­cal tar­get detec­tion has been shown to be mod­u­lat­ed by slow oscil­la­to­ry brain phase. How­ev­er, thus far, only low-lev­el sen­so­ry stim­uli have been used as tar­gets. The cur­rent human elec­troen­cephalog­ra­phy (EEG) study exam­ined the influ­ence of neur­al oscil­la­to­ry phase on a lex­i­cal-deci­sion task per­formed for stim­uli embed­ded in noise. Neur­al phase angles were com­pared for cor­rect ver­sus incor­rect lex­i­cal deci­sions using a phase bifur­ca­tion index (BI), which quan­ti­fies dif­fer­ences in mean phase angles and phase con­cen­tra­tions between cor­rect and incor­rect tri­als. Neur­al phase angles in the alpha fre­quen­cy range (8–12 Hz) over right ante­ri­or sen­sors were approx­i­mate­ly antiphase in a pres­tim­u­lus time win­dow, and thus suc­cess­ful­ly dis­tin­guished between cor­rect and incor­rect lex­i­cal deci­sions. More­over, alpha-band oscil­la­tions were again approx­i­mate­ly antiphase across par­tic­i­pants for cor­rect ver­sus incor­rect tri­als dur­ing a lat­er peri­s­tim­u­lus time win­dow (∼500 ms) at left-cen­tral elec­trodes. Strik­ing­ly, lex­i­cal deci­sion accu­ra­cy was not pre­dict­ed by either event-relat­ed poten­tials (ERPs) or oscil­la­to­ry pow­er mea­sures. We sug­gest that cor­rect lex­i­cal deci­sions depend both on suc­cess­ful sen­so­ry pro­cess­ing, which is made pos­si­ble by the align­ment of stim­u­lus onset with an opti­mal alpha phase, as well as inte­gra­tion and weight­ing of deci­sion­al infor­ma­tion, which is cou­pled to alpha phase imme­di­ate­ly fol­low­ing the crit­i­cal manip­u­la­tion that dif­fer­en­ti­at­ed words from pseu­do­words. The cur­rent study con­sti­tutes a first step toward char­ac­ter­iz­ing the role of dynam­ic oscil­la­to­ry brain states for high­er cog­ni­tive func­tions, such as spo­ken word recognition.
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Editorial Notes

2015 — Embrac­ing Change in the Obleser Lab

Time flies: The Audi­to­ry Cog­ni­tion group aka The Obleser Lab has just entered its fifth year. We took off prop­er­ly in ear­ly 2011, so this is a good point in time to briefly recap. We have had four excit­ing and very pro­duc­tive years so far, and this fifth year is bring­ing a lot of excit­ing turn-over as well. First, new faces have joined our group:

Dr. Sophie Herb­st a psy­chol­o­gist with keen inter­ests in time per­cep­tion joined us as a post­doc, com­ing from Niko Busch’s lab at the Char­ité Berlin.

Dipl.-Ing. (FH) Lorenz Fiedler joined us to help us build real-time links between EEG and hear­ing aids, as planned in our Volk­swa­gen project.

Sec­ond, a few great tal­ents have moved on with the begin­ning of 2015:

Antje Strauß just received her Dr. rer. nat. (PhD) from the Uni­ver­si­ty of Leipzig and is now at the GIPSA lab, Uni­ver­si­ty of Greno­ble, France.

Dr. Mol­ly Hen­ry and Dr. Björn Her­rmann have both tak­en up new Post­doc­tor­al jobs at the Uni­ver­si­ty of West­ern Ontario, Lon­don, Ontario, CA. They will be work­ing with Jes­si­ca Grahn and Ingrid John­srude, respec­tive­ly.

Dr. Alex Brand­mey­er could not resist a fan­tas­tic offer by Dol­by Sys­tems Inc., San Fran­cis­co to join them as a research scientist.

Ear­li­er in autumn 2014 already, Julia Erb had tak­en up a post­doc posi­tion with Elia Formisano at the Uni­ver­si­ty of Maas­tricht.

… the best of luck and many thanks to all the new AC alumni!

Last­ly, Jonas as head of the group has just been appoint­ed Pro­fes­sor for Research Meth­ods and Sta­tis­tics at the (new­ly-found­ed) Depart­ment of Psy­chol­o­gy, Uni­ver­si­ty of Lübeck, Ger­many.

These great news also imply that the Audi­to­ry Cog­ni­tion group as a whole will, as con­ceived by the Max Planck Soci­ety when pro­vid­ing this five-year start-up fund­ing, slow­ly trans­plant to a new place, name­ly: Lübeck, over the year to come. Watch this space! Yet, the labels “auditorycognition.com” and “obleserlab.com” will sure­ly remain active and move with us.

Categories
Degraded Acoustics EEG / MEG Linguistics Neural Oscillations Neural Phase Papers Perception Publications Speech

New paper in press in the Jour­nal of Neu­ro­science: Strauß, Hen­ry, Scharinger, & Obleser

Con­grat­u­la­tions to just-grad­u­at­ed for­mer AC PhD stu­dent and fresh GIPSA/Grenoble Post­doc Antje Strauß, who today had the last data set from her PhD the­sis accept­ed as a paper in The Jour­nal of Neu­ro­science. We are all very happy!

The paper is enti­tled “Alpha phase deter­mines suc­cess­ful lex­i­cal deci­sion in noise” and con­tains arguably the first data set to extend prin­ci­ples of (alpha, 8–12 Hz) pre-stim­u­lus phase depen­dence from low-lev­el psy­chophysics to more com­plex lan­guage or cog­ni­tive process­es, here: lex­i­cal decision.

A big hel­lo to AC friend and col­league Niko Busch, by the way, whose bifur­ca­tion index mea­sure served our pur­pos­es very well here!

We will update accord­ing­ly, but mean­while, here is the abstract and my favourite fig­ure from the paper.

Abstract
Psy­chophys­i­cal tar­get detec­tion has been shown to be mod­u­lat­ed by slow oscil­la­to­ry brain phase. How­ev­er, thus far, only low-lev­el sen­so­ry stim­uli have been used as tar­gets. The cur­rent human elec­troen­cephalog­ra­phy study exam­ined the influ­ence of neur­al oscil­la­to­ry phase on a lex­i­cal-deci­sion task per­formed for stim­uli embed­ded in noise. Neur­al phase angles were com­pared for cor­rect ver­sus incor­rect lex­i­cal deci­sions using a phase bifur­ca­tion index, which quan­ti­fies dif­fer­ences in mean phase angles and phase con­cen­tra­tions between cor­rect and incor­rect tri­als. Neur­al phase angles in the alpha fre­quen­cy range (8–12 Hz) over right ante­ri­or sen­sors were approx­i­mate­ly anti-phase in a pre-stim­u­lus time win­dow, and thus suc­cess­ful­ly dis­tin­guished between cor­rect and incor­rect lex­i­cal deci­sions. More­over, alpha-band oscil­la­tions were again approx­i­mate­ly anti-phase across par­tic­i­pants for cor­rect ver­sus incor­rect tri­als dur­ing a lat­er peri-stim­u­lus time-win­dow (around 500 ms) at left-cen­tral elec­trodes. Strik­ing­ly, lex­i­cal deci­sion accu­ra­cy was not pre­dict­ed by either ERPs or oscil­la­to­ry pow­er mea­sures. We sug­gest that cor­rect lex­i­cal deci­sions depend both on suc­cess­ful sen­so­ry pro­cess­ing, which is made pos­si­ble by the align­ment of stim­u­lus onset with an opti­mal alpha phase, as well as inte­gra­tion and weight­ing of deci­sion­al infor­ma­tion, which is cou­pled to alpha phase imme­di­ate­ly fol­low­ing the crit­i­cal manip­u­la­tion that dif­fer­en­ti­at­ed words from pseu­do­words. The cur­rent study con­sti­tutes a first step towards char­ac­ter­iz­ing the role of dynam­ic oscil­la­to­ry brain states for high­er cog­ni­tive func­tions such as spo­ken word recognition.

Untitled copy

Categories
Ageing Auditory Perception Degraded Acoustics EEG / MEG Hearing Loss Neural Oscillations Papers Perception Publications Speech

Strauß strikes again — fron­tiers in Human Neuroscience

It’s only a week ago that we updat­ed you about Antje’s lat­est pub­li­ca­tion at Neu­roIm­age. Today, there is a anoth­er one com­ing in; Antje’s, Mal­te’s & Jonas’ per­spec­tive arti­cle on cor­ti­cal alpha oscil­la­tions is in press at fron­tiers in HUMAN NEUROSCIENCE.

Cor­ti­cal alpha oscil­la­tions as a tool for audi­to­ry selec­tive inhibition

— Strauß, Wöst­mann & Obleser

See abstract
Lis­ten­ing to speech is often demand­ing because of sig­nal degra­da­tions and the pres­ence of dis­tract­ing sounds (i.e., “noise”). The ques­tion how the brain achieves the task of extract­ing only rel­e­vant infor­ma­tion from the mix­ture of sounds reach­ing the ear (i.e., “cock­tail par­ty prob­lem”) is still open. In anal­o­gy to recent find­ings in vision, we pro­pose cor­ti­cal alpha (~10 Hz) oscil­la­tions mea­sur­able using M/EEG as a piv­otal mech­a­nism to selec­tive­ly inhib­it the pro­cess­ing of noise to improve audi­to­ry selec­tive atten­tion to task-rel­e­vant sig­nals. We review ini­tial evi­dence of enhanced alpha activ­i­ty in selec­tive lis­ten­ing tasks, sug­gest­ing a sig­nif­i­cant role of alpha-mod­u­lat­ed noise sup­pres­sion in speech. We dis­cuss the impor­tance of dis­so­ci­at­ing between noise inter­fer­ence in the audi­to­ry periph­ery (i.e., ener­getic mask­ing) and noise inter­fer­ence with more cen­tral cog­ni­tive aspects of speech pro­cess­ing (i.e., infor­ma­tion­al mask­ing). Final­ly, we point out the adverse effects of age-relat­ed hear­ing loss and/or cog­ni­tive decline on audi­to­ry selec­tive inhi­bi­tion. With this per­spec­tive arti­cle, we set the stage for future stud­ies on the inhibito­ry role of alpha oscil­la­tions for speech pro­cess­ing in chal­leng­ing lis­ten­ing situations.

Ref­er­ences

  • Strauß A1, Wöst­mann M2, Obleser J1. Cor­ti­cal alpha oscil­la­tions as a tool for audi­to­ry selec­tive inhi­bi­tion. Front Hum Neu­rosci. 2014 May 28;8:350. PMID: 24904385. [Open with Read]
Categories
EEG / MEG Linguistics Neural Oscillations Papers Publications

New paper out: Dis­so­ci­a­tion of alpha and theta oscil­la­tions Strauß, Kotz, Scharinger, Obleser

We are very hap­py to announce that PhD stu­dent Antje Strauß got her paper

Alpha and theta brain oscil­la­tions index dis­so­cia­ble process­es in spo­ken word recognition

accept­ed at Neu­roIm­age. Con­grat­u­la­tions! Find her paper here.

See the Abstract
Slow neur­al oscil­la­tions (∼ 1–15 Hz) are thought to orches­trate the neur­al process­es of spo­ken lan­guage com­pre­hen­sion. How­ev­er, func­tion­al sub­di­vi­sions with­in this broad range of fre­quen­cies are dis­put­ed, with most stud­ies hypoth­e­siz­ing only about sin­gle fre­quen­cy bands. The present study uti­lizes an estab­lished par­a­digm of spo­ken word recog­ni­tion (lex­i­cal deci­sion) to test the hypoth­e­sis that with­in the slow neur­al oscil­la­to­ry fre­quen­cy range, dis­tinct func­tion­al sig­na­tures and cor­ti­cal net­works can be iden­ti­fied at least for theta- (∼ 3–7 Hz) and alpha-fre­quen­cies (∼ 8–12 Hz). Lis­ten­ers per­formed an audi­to­ry lex­i­cal deci­sion task on a set of items that formed a word–pseudoword con­tin­u­um: rang­ing from (1) real words over (2) ambigu­ous pseu­do­words (devi­at­ing from real words only in one vow­el; com­pa­ra­ble to nat­ur­al mis­pro­nun­ci­a­tions in speech) to (3) pseu­do­words (clear­ly devi­at­ing from real words by ran­dom­ized syl­la­bles). By means of time–frequency analy­sis and spa­tial fil­ter­ing, we observed a dis­so­ci­a­tion into dis­tinct but simul­ta­ne­ous pat­terns of alpha pow­er sup­pres­sion and theta pow­er enhance­ment. Alpha exhib­it­ed a para­met­ric sup­pres­sion as items increas­ing­ly matched real words,in line with low­ered func­tion­al inhi­bi­tion in a left-dom­i­nant lex­i­cal pro­cess­ing net­work for more word-like input. Simul­ta­ne­ous­ly, theta pow­er in a bilat­er­al fron­to-tem­po­ral net­work was selec­tive­ly enhanced for ambigu­ous pseu­do­words only. Thus, enhanced alpha pow­er can neu­ral­ly “gate” lex­i­cal inte­gra­tion, while enhanced theta pow­er might index func­tion­al­ly more spe­cif­ic ambi­gu­i­ty-res­o­lu­tion process­es. To this end, a joint analy­sis of both fre­quen­cy bands pro­vides neur­al evi­dence for par­al­lel process­es in achiev­ing spo­ken word recognition.

Ref­er­ences

  • Strauβ A1, Kotz SA2, Scharinger M3, Obleser J3. Alpha and theta brain oscil­la­tions index dis­so­cia­ble process­es in spo­ken word recog­ni­tion. Neu­roim­age. 2014 Apr 18. PMID: 24747736. [Open with Read]
Categories
EEG / MEG Neural Oscillations Perception Posters Publications

Col­in Cher­ry Award 2014 goes to Malte Wöstmann

On this years SPIN (Speech in Noise) work­shop in Mar­seille, our very own Malte Wöst­mann received the Col­in Cher­ry  Best Poster Award, elect­ed by work­shop attendees.

Judge for your­self and check out the Poster (PDF) here. 

Colin Cherry Award 2014 goes to Malte Wöstmann
Col­in Cher­ry Award 2014 goes to Malte Wöstmann
Categories
Editorial Notes Events Media Publications

SNAP sum­ma­ry and impressions

The SNAP work­shop (Sig­nal and Noise along the Audi­to­ry Path­way) is behind us.

It is safe to say that it has been a great suc­cess. We will care­ful­ly look into the eval­u­a­tion forms you pro­vid­ed, and we will inform here in due course whether and when a 2nd SNAP (poten­tial­ly 2015) is in the making.

Let us thank all of you who made SNAP hap­pen. It turned a fun and suc­cess­ful sci­en­tif­ic year 2013 into an even greater one. Thank you! We hope to see you soon again, somewhere.

Now, here are some impres­sions of SNAP 2013:

P.S. Here you find Jonas’ clos­ing sum­ma­ry notes:

SNAP 2013 ad hoc sum­ma­ry — Jonas Obleser

 

Categories
Editorial Notes Events

SNAP Day 1 is behind us

A great day 1 of the SNAP work­shop is behind us. It could go on for­ev­er, if it would be accord­ing to me.

While Thomas Lun­ner was sad­ly stopped short by new pro­gram com­mit­tee mem­ber, pan-Euro­pean storm ras­cal “Xaver”, 45 oth­ers made it suc­ces­ful­ly to the Max Planck in Leipzig, wit­ness­ing Ingrid John­srude, Torsten Dau, Alexan­dra Ben­dix­en, Maria Chait, Jonathan Peelle, and Peter Lakatos bring­ing the house down.

With the speak­ers’ sup­port, I will poten­tial­ly post a sum­ma­ry pdf of my clos­ing remarks, which I will give tomor­row, for pub­lic access.

As for now, feel free to fol­low Car­olyn McGet­ti­gan and Jonathan Peelle cov­er­ing some of it as SNAP con­tin­ues into day 2 (#SNAPleipzig).

SNAP 2013 Group Photo