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Degraded Acoustics EEG / MEG fMRI Linguistics Papers Publications

New paper out: Simul­ta­ne­ous fMRI–EEG in audi­to­ry cat­e­go­riza­tion by Scharinger et al.

Con­grat­u­la­tions to Obleser lab alum­nus Math­ias Scharinger who this week pub­lished our joint work on simul­ta­ne­ous fMRI–EEG in Fron­tiers in Human Neuroscience!

Simul­ta­ne­ous EEG-fMRI brain sig­na­tures of audi­to­ry cue utilization

by Scharinger, Her­rmann, Nier­haus, & Obleser

See abstract
Opti­mal uti­liza­tion of acoustic cues dur­ing audi­to­ry cat­e­go­riza­tion is a vital skill, par­tic­u­lar­ly when infor­ma­tive cues become occlud­ed or degrad­ed. Con­se­quent­ly, the acoustic envi­ron­ment requires flex­i­ble choos­ing and switch­ing amongst avail­able cues. The present study tar­gets the brain func­tions under­ly­ing such changes in cue uti­liza­tion. Par­tic­i­pants per­formed a cat­e­go­riza­tion task with imme­di­ate feed­back on acoustic stim­uli from two cat­e­gories that var­ied in dura­tion and spec­tral prop­er­ties, while we simul­ta­ne­ous­ly record­ed Blood Oxy­gena­tion Lev­el Depen­dent (BOLD) respons­es in fMRI and elec­troen­cephalo­grams (EEGs). In the first half of the exper­i­ment, cat­e­gories could be best dis­crim­i­nat­ed by spec­tral prop­er­ties. Halfway through the exper­i­ment, spec­tral degra­da­tion ren­dered the stim­u­lus dura­tion the more infor­ma­tive cue. Behav­ioral­ly, degra­da­tion decreased the like­li­hood of uti­liz­ing spec­tral cues. Spec­tral­ly degrad­ing the acoustic sig­nal led to increased alpha pow­er com­pared to non­de­grad­ed stim­uli. The EEG-informed fMRI analy­ses revealed that alpha pow­er cor­re­lat­ed with BOLD changes in infe­ri­or pari­etal cor­tex and right pos­te­ri­or supe­ri­or tem­po­ral gyrus (includ­ing planum tem­po­rale). In both areas, spec­tral degra­da­tion led to a weak­er cou­pling of BOLD response to behav­ioral uti­liza­tion of the spec­tral cue. These data pro­vide con­verg­ing evi­dence from behav­ioral mod­el­ing, elec­tro­phys­i­ol­o­gy, and hemo­dy­nam­ics that (a) increased alpha pow­er medi­ates the inhi­bi­tion of unin­for­ma­tive (here spec­tral) stim­u­lus fea­tures, and that (b) the pari­etal atten­tion net­work sup­ports opti­mal cue uti­liza­tion in audi­to­ry cat­e­go­riza­tion. The results high­light the com­plex cor­ti­cal pro­cess­ing of audi­to­ry cat­e­go­riza­tion under real­is­tic lis­ten­ing chal­lenges.

Ref­er­ences

  • Scharinger M1, Her­rmann B1, Nier­haus T2, Obleser J1. Simul­ta­ne­ous EEG-fMRI brain sig­na­tures of audi­to­ry cue uti­liza­tion. Front Neu­rosci. 2014 Jun 4;8:137. PMID: 24926232. [Open with Read]
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
Auditory Perception Auditory Working Memory Events fMRI Neural Oscillations Neural Phase Posters

Come and find us at CNS 2014 in Boston this weekend

The Obleser lab will be pre­sent­ing four posters at this year’s Annu­al Meet­ing of the Cog­ni­tive Neu­ro­science Soci­ety in Boston.

If you hap­pen to be there, come check us out!

A125Hemo­dy­nam­ic sig­na­tures of (mis-)perceiving tem­po­ral change
Her­rmann, Bjoern

C63Tem­po­ral pre­dictabil­i­ty atten­u­ates decay in sen­so­ry memory
Wilsch, Anna

D54Stim­u­lus dis­crim­inabil­i­ty and pre­dic­tive­ness mod­u­late alpha oscil­la­tions in a per­cep­tu­al­ly demand­ing mem­o­ry task
Wöst­mann, Malte

D130Slow acoustic fluc­tu­a­tions entrain low-fre­quen­cy neur­al oscil­la­tions and deter­mine psy­choa­coustic performance
Hen­ry, Molly

Categories
Auditory Working Memory Degraded Acoustics EEG / MEG Executive Functions Neural Oscillations Papers Publications Speech

New Paper out: Wilsch, Hen­ry, Her­rmann et al.

Quite recent­ly Cere­bral Cor­tex published

Alpha Oscil­la­to­ry Dynam­ics Index Tem­po­ral Expec­ta­tion Ben­e­fits in Work­ing Memory

by Anna Wilsch, Mol­ly J Hen­ry, Björn Her­rmann, Burkhard Maess, and Jonas Obleser.

Check the abstract below or fol­low that link to get the full arti­cle.

Abstract
Enhanced alpha pow­er com­pared with a base­line can reflect states of increased cog­ni­tive load, for exam­ple, when lis­ten­ing to speech in noise. Can knowl­edge about “when” to lis­ten (tem­po­ral expec­ta­tions) poten­tial­ly coun­ter­act cog­ni­tive load and con­comi­tant­ly reduce alpha? The cur­rent mag­ne­toen­cephalog­ra­phy (MEG) exper­i­ment induced cog­ni­tive load using an audi­to­ry delayed-match­ing-to-sam­ple task with 2 syl­la­bles S1 and S2 pre­sent­ed in speech-shaped noise. Tem­po­ral expec­ta­tion about the occur­rence of S1 was manip­u­lat­ed in 3 dif­fer­ent cue con­di­tions: “Neu­tral” (unin­for­ma­tive about forepe­ri­od), “ear­ly-cued” (short forepe­ri­od), and “late-cued” (long forepe­ri­od). Alpha pow­er through­out the tri­al was high­est when the cue was unin­for­ma­tive about the onset time of S1 (neu­tral) and low­est for the late-cued con­di­tion. This alpha-reduc­ing effect of late com­pared with neu­tral cues was most evi­dent dur­ing mem­o­ry reten­tion in noise and orig­i­nat­ed pri­mar­i­ly in the right insu­la. More­over, indi­vid­ual alpha effects dur­ing reten­tion account­ed best for observed indi­vid­ual per­for­mance dif­fer­ences between late-cued and neu­tral con­di­tions, indi­cat­ing a trade­off between allo­ca­tion of neur­al resources and the ben­e­fits drawn from tem­po­ral cues. Over­all, the results indi­cate that tem­po­ral expec­ta­tions can facil­i­tate the encod­ing of speech in noise, and con­comi­tant­ly reduce neur­al mark­ers of cog­ni­tive load.

Ref­er­ences

  • Wilsch A, Hen­ry MJ, Her­rmann B, Maess B, Obleser J. Alpha Oscil­la­to­ry Dynam­ics Index Tem­po­ral Expec­ta­tion Ben­e­fits in Work­ing Mem­o­ry. Cereb Cor­tex. 2014 Jan 31. PMID: 24488943. [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
Auditory Cortex Auditory Neuroscience Auditory Perception EEG / MEG Evoked Activity Papers Perception Publications

New paper in press: Her­rmann, Schlicht­ing, & Obleser, Jour­nal of Neuroscience

Björn Her­rmann has yet anoth­er paper in press in the Jour­nal of Neuroscience!

Dynam­ic Range Adap­ta­tion to Spec­tral Stim­u­lus Sta­tis­tics in Human Audi­to­ry Cortex

The paper is now avail­able online free of charge, and—funnily enough—appeared right on Jan­u­ary 1, 2014.

Screen Shot 2014-01-02 at 14.38.58

Ref­er­ences

  • Her­rmann B, Schlicht­ing N, Obleser J. Dynam­ic range adap­ta­tion to spec­tral stim­u­lus sta­tis­tics in human audi­to­ry cor­tex. J Neu­rosci. 2014 Jan 1;34(1):327–31. PMID: 24381293. [Open with Read]
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