web analytics

Category: Speech

Categories
Auditory Cortex Auditory Perception Media Neural Oscillations Papers Publications Uncategorized

New fea­turette in eLife: Tell me some­thing I don’t know

For those inter­est­ed in audi­to­ry cor­tex and how a regime of pre­dic­tions, pre­dic­tion updates and sur­prise (a ver­sion of “pre­dic­tion error”) might be imple­ment­ed there, I con­tributed a brief fea­turette (“insight”, they call it) to eLife on a recent paper by Will Sed­ley, Tim Grif­fiths, and oth­ers. Check it out.
Obleser-elife-Figure

[For those not so famil­iar with it, “eLife”, despite its aes­thet­i­cal­ly ques­tion­able name, pos­es an inter­est­ing and rel­a­tive­ly new, high-pro­file, open-access pub­lish­ing effort by nobel-prize-win­ning Randy Schek­man, for­mer SfN pres­i­dent Eve Marder and others.] 
Categories
Auditory Cortex Auditory Neuroscience Auditory Perception Auditory Speech Processing Editorial Notes EEG / MEG Executive Functions Neural Oscillations Neural Phase Papers Publications Speech Uncategorized

[UPDATE] New paper in PNAS: Spa­tiotem­po­ral dynam­ics of audi­to­ry atten­tion syn­chro­nize with speech, Woest­mann et al.

Wöst­mann, Her­rmann, Maess and Obleser demon­strate that the hemi­spher­ic lat­er­al­iza­tion of neur­al alpha oscil­la­tions mea­sured in the mag­ne­toen­cephalo­gram (MEG) syn­chro­nizes with the speech sig­nal and pre­dicts lis­ten­ers’ speech comprehension.

Now avail­able online:

http://www.pnas.org/content/early/2016/03/18/1523357113

Press release:

https://www.uni-luebeck.de/forschung/aktuelles-zur-forschung/aktuelles-zur-forschung/artikel/aufmerksamkeit-in-wellen-erfolgreich-zuhoeren-im-rhythmus-der-sprache.html

spatiotemporal_dynamics

Abstract
Atten­tion plays a fun­da­men­tal role in selec­tive­ly pro­cess­ing stim­uli in our envi­ron­ment despite dis­trac­tion. Spa­tial atten­tion induces increas­ing and decreas­ing pow­er of neur­al alpha oscil­la­tions (8–12 Hz) in brain regions ipsi­lat­er­al and con­tralat­er­al to the locus of atten­tion, respec­tive­ly. This study test­ed whether the hemi­spher­ic lat­er­al­iza­tion of alpha pow­er codes not just the spa­tial loca­tion but also the tem­po­ral struc­ture of the stim­u­lus. Par­tic­i­pants attend­ed to spo­ken dig­its pre­sent­ed to one ear and ignored tight­ly syn­chro­nized dis­tract­ing dig­its pre­sent­ed to the oth­er ear. In the mag­ne­toen­cephalo­gram, spa­tial atten­tion induced lat­er­al­iza­tion of alpha pow­er in pari­etal, but notably also in audi­to­ry cor­ti­cal regions. This alpha pow­er lat­er­al­iza­tion was not main­tained steadi­ly but fluc­tu­at­ed in syn­chrony with the speech rate and lagged the time course of low-fre­quen­cy (1–5 Hz) sen­so­ry syn­chro­niza­tion. High­er ampli­tude of alpha pow­er mod­u­la­tion at the speech rate was pre­dic­tive of a listener’s enhanced per­for­mance of stream-spe­cif­ic speech com­pre­hen­sion. Our find­ings demon­strate that alpha pow­er lat­er­al­iza­tion is mod­u­lat­ed in tune with the sen­so­ry input and acts as a spa­tiotem­po­ral fil­ter con­trol­ling the read-out of sen­so­ry content.
Categories
Auditory Cortex Auditory Neuroscience Auditory Perception EEG / MEG Neural Oscillations Papers Publications Speech

New paper: Her­rmann, Hen­ry, Hae­gens & Obleser in Neuroimage

And again, AC-Alum­ni Björn Her­rmann got a new paper in press / online at Neu­roIm­age on

Tem­po­ral expec­ta­tions and neur­al ampli­tude fluc­tu­a­tions in audi­to­ry cor­tex inter­ac­tive­ly influ­ence perception

Abstract
Align­ment of neur­al oscil­la­tions with tem­po­ral­ly reg­u­lar input allows lis­ten­ers to gen­er­ate tem­po­ral expec­ta­tions. How­ev­er, it remains unclear how behav­ior is gov­erned in the con­text of tem­po­ral vari­abil­i­ty: What role do tem­po­ral expec­ta­tions play, and how do they inter­act with the strength of neur­al oscil­la­to­ry activ­i­ty? Here, human par­tic­i­pants detect­ed near-thresh­old tar­gets in tem­po­ral­ly vari­able acoustic sequences. Tem­po­ral expec­ta­tion strength was esti­mat­ed using an oscil­la­tor mod­el and pre-tar­get neur­al ampli­tudes in audi­to­ry cor­tex were extract­ed from mag­ne­toen­cephalog­ra­phy sig­nals. Tem­po­ral expec­ta­tions mod­u­lat­ed tar­get-detec­tion per­for­mance, how­ev­er, only when neur­al delta-band ampli­tudes were large. Thus, slow neur­al oscil­la­tions act to gate influ­ences of tem­po­ral expec­ta­tion on per­cep­tion. Fur­ther­more, slow ampli­tude fluc­tu­a­tions gov­erned lin­ear and qua­drat­ic influ­ences of audi­to­ry alpha-band activ­i­ty on per­for­mance. By fus­ing a mod­el of tem­po­ral expec­ta­tion with neur­al oscil­la­to­ry dynam­ics, the cur­rent find­ings show that human per­cep­tion in tem­po­ral­ly vari­able con­texts relies on com­plex inter­ac­tions between mul­ti­ple neur­al fre­quen­cy bands.

Cheers.

Ref­er­ences

  • Her­rmann B1, Hen­ry MJ2, Hae­gens S3, Obleser J4. Tem­po­ral expec­ta­tions and neur­al ampli­tude fluc­tu­a­tions in audi­to­ry cor­tex inter­ac­tive­ly influ­ence per­cep­tion. Neu­roim­age. 2015 Sep 18;124(Pt A):487–497. PMID: 26386347. [Open with Read]
Categories
Ageing Auditory Speech Processing Degraded Acoustics Hearing Loss Media Publications Speech

Quick inter­view for detektor.fm

Based on Malte’s recent J Neu­rosci study, Jonas did a brief inter­view for Ger­man radio detektor.fm today and talked lis­ten­ing effort, dig­i­tal phone lines, noise reduc­tion, and next-gen­er­a­tion hear­ing aids with host Tere­sa Nehm. (In Ger­man only.)

Categories
Auditory Speech Processing EEG / MEG Linguistics Papers Publications Speech

New edi­to­r­i­al in “Brain & Lan­guage”: Re-vis­it­ing the elec­tro­phys­i­ol­o­gy of language

I had the hon­our of guest-edit­ing a spe­cial issue for the clas­sic jour­nal “Brain and Lan­guage” and have thus con­tributed a brief edi­to­r­i­al (now online) to this issue. The spe­cial issue re-vis­its old themes and new leads in the elec­tro­phys­i­ol­o­gy of speech, lan­guage, and its precursors.

UPDATE: The full spe­cial issue appeared in Sep­tem­ber 2015 and all arti­cles are now acces­si­ble and citable. Thanks for your kind attention!

Categories
Auditory Cortex Auditory Neuroscience Clinical relevance Degraded Acoustics EEG / MEG Executive Functions Hearing Loss Media Neural Oscillations Papers Publications Speech

Max Planck Soci­ety reports on Wöst­mann et al.’s Neur­al alpha dynamics

Some days ago the Max Planck Soci­ety put out a news fea­ture on our most recent Jour­nal of Neu­ro­science paper (see our post):

Aufmerk­sam zuhören — Hirn-Wellen zeigen Mühen des Hörens im Alter an

Sum­ma­ry
Ältere Men­schen kla­gen oft über Hörschwierigkeit­en, beson­ders wenn mehrere Per­so­n­en durcheinan­der sprechen. Forsch­er am Max-Planck-Insti­tut für Kog­ni­tions- und Neu­rowis­senschaften in Leipzig haben her­aus­ge­fun­den, dass der Grund hier­für nicht nur im Ohr, son­dern eben­so in verän­derten Aufmerk­samkeit­sprozessen im Gehirn älter­er Men­schen zu find­en ist. Eine beson­dere Bedeu­tung kommt dabei den Alpha-Wellen zu, deren Anpas­sung an verän­derte Hör­si­t­u­a­tio­nen das Sprachver­ständ­nis in All­t­agssi­t­u­a­tio­nen verbessert.

It nice­ly wraps up Malte’s exper­i­ment on alpha dynam­ics in younger and old­er lis­ten­ers. Check the link above for the full arti­cle (Ger­man).

 

Ref­er­ences

  • Wöst­mann M1, Her­rmann B2, Wilsch A2, Obleser J3. Neur­al alpha dynam­ics in younger and old­er lis­ten­ers reflect acoustic chal­lenges and pre­dic­tive ben­e­fits. J Neu­rosci. 2015 Jan 28;35(4):1458–67. PMID: 25632123. [Open with Read]
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 Cortex Auditory Neuroscience Clinical relevance Degraded Acoustics EEG / MEG Executive Functions Hearing Loss Neural Oscillations Papers Publications Speech

New paper in press in the Jour­nal of Neu­ro­science: Wöst­mann, Her­rmann, Wilsch, & Obleser [UPDATED #2]

Con­grat­u­la­tions to AC PhD stu­dent Malte Wöst­mann for his new­ly accept­ed paper in the Jour­nal of Neu­ro­science!

Wöst­mann M, Her­rmann B, Wilsch A, & Obleser J.

Neur­al alpha dynam­ics in younger and old­er lis­ten­ers reflect acoustic chal­lenges and pre­dic­tive benefits

J Neu­rosci, in press.

Here is the abstract and my favourite fig­ure from Malte’s paper.

Abstract
Speech com­pre­hen­sion in mul­ti-talk­er sit­u­a­tions is a noto­ri­ous real-life chal­lenge, par­tic­u­lar­ly for old­er lis­ten­ers. Younger lis­ten­ers exploit stim­u­lus-inher­ent acoustic detail, but are they also active­ly pre­dict­ing upcom­ing infor­ma­tion? And fur­ther, how do old­er lis­ten­ers deal with acoustic and pre­dic­tive infor­ma­tion? To under­stand the neur­al dynam­ics of lis­ten­ing dif­fi­cul­ties and accord­ing lis­ten­ing strate­gies, we con­trast­ed neur­al respons­es in the alpha-band (~10 Hz) in younger (20−30 years, n = 18) and healthy old­er (60−70 years, n = 20) par­tic­i­pants under chang­ing task demands in a two-talk­er par­a­digm. Elec­troen­cephalo­grams were record­ed while humans lis­tened to two spo­ken dig­its against a dis­tract­ing talk­er and decid­ed whether the sec­ond dig­it was small­er or larg­er. Acoustic detail (tem­po­ral fine struc­ture) and pre­dic­tive­ness (the degree to which the first dig­it pre­dict­ed the sec­ond) var­ied orthog­o­nal­ly. Alpha pow­er at wide­spread scalp sites decreased with increas­ing acoustic detail (dur­ing tar­get dig­it pre­sen­ta­tion) but also with increas­ing pre­dic­tive­ness (in-between tar­get dig­its). For old­er com­pared to younger lis­ten­ers, acoustic detail had a stronger impact on task per­for­mance and alpha pow­er mod­u­la­tion. This sug­gests that alpha dynam­ics plays an impor­tant role in the changes in lis­ten­ing behav­ior that occur with age. Last­ly, alpha pow­er vari­a­tions result­ing from stim­u­lus manip­u­la­tions (of acoustic detail and pre­dic­tive­ness) as well as task-inde­pen­dent over­all alpha pow­er were relat­ed to sub­jec­tive lis­ten­ing effort. The present data show that alpha dynam­ics is a promis­ing neur­al mark­er of indi­vid­ual dif­fi­cul­ties as well as age-relat­ed changes in sen­sa­tion, per­cep­tion, and com­pre­hen­sion in com­plex com­mu­ni­ca­tion situations. 

Screen Shot 2014-12-03 at 13.07.13

Update #2

Ger­man radio broad­cast­er MDR Info did an inter­view & fea­ture on Mal­te’s Exper­i­ment. Check out the stream below:

Ref­er­ences

  • Wöst­mann M1, Her­rmann B2, Wilsch A2, Obleser J3. Neur­al alpha dynam­ics in younger and old­er lis­ten­ers reflect acoustic chal­lenges and pre­dic­tive ben­e­fits. J Neu­rosci. 2015 Jan 28;35(4):1458–67. PMID: 25632123. [Open with Read]