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Attention Auditory Cortex Auditory Perception Brain stimulation Papers Psychology Publications Speech

New paper in press in Brain Stim­u­la­tion: Wöst­mann, Vosskuhl, Obleser, and Her­rmann demon­strate that exter­nal­ly ampli­fied oscil­la­tions affect audi­to­ry spa­tial attention

In a fine col­lab­o­ra­tion we com­bine exper­tise on audi­to­ry cog­ni­tion (Malte Wöst­mann & Jonas Obleser, Uni­ver­si­ty of Lübeck) and brain stim­u­la­tion (Johannes Vosskuhl and Christoph S Her­rmann, Uni­ver­si­ty of Old­en­burg) to show that exter­nal­ly stim­u­lat­ed alpha and gam­ma oscil­la­tions dif­fer­en­tial­ly affect spa­tial atten­tion to speech. Our par­tic­i­pants per­formed a dichot­ic lis­ten­ing task while being stim­u­lat­ed using tran­scra­nial alter­nat­ing cur­rent stim­u­la­tion (tACS) at alpha or gam­ma fre­quen­cy (vs sham) on the left hemi­sphere. Alpha-tACS rel­a­tive­ly decreased recall of tar­gets con­tralat­er­al to stim­u­la­tion, while gam­ma-tACS reversed this effect. These results sug­gest that exter­nal­ly ampli­fied oscil­la­tions are func­tion­al­ly rel­e­vant to spa­tial attention.

Wöst­mann, M., Vosskuhl, J., Obleser, J., & Her­rmann, C.S. (2018). Oppo­site effects of lat­er­alised tran­scra­nial alpha ver­sus gam­ma stim­u­la­tion on audi­to­ry spa­tial attention.

Now avail­able online:

https://www.sciencedirect.com/science/article/pii/S1935861X18301074

Abstract:

Back­groundSpa­tial atten­tion rel­a­tive­ly increas­es the pow­er of neur­al 10-Hz alpha oscil­la­tions in the hemi­sphere ipsi­lat­er­al to atten­tion, and decreas­es alpha pow­er in the con­tralat­er­al hemi­sphere. For gam­ma oscil­la­tions (>40 Hz), the oppo­site effect has been observed. The func­tion­al roles of lat­er­alised oscil­la­tions for atten­tion are cur­rent­ly unclear.

Hypoth­e­sis: If lat­er­alised oscil­la­tions are func­tion­al­ly rel­e­vant for atten­tion, tran­scra­nial stim­u­la­tion of alpha ver­sus gam­ma oscil­la­tions in one hemi­sphere should dif­fer­en­tial­ly mod­u­late the accu­ra­cy of spa­tial atten­tion to the ipsi-ver­sus con­tralat­er­al side.

Meth­ods: 20 human par­tic­i­pants per­formed a dichot­ic lis­ten­ing task under con­tin­u­ous tran­scra­nial alter­nat­ing cur­rent stim­u­la­tion (tACS, vs sham) at alpha (10 Hz) or gam­ma (47 Hz) fre­quen­cy. On each tri­al, par­tic­i­pants attend­ed to four spo­ken num­bers on the left or right ear, while ignor­ing num­bers on the oth­er ear. In order to stim­u­late a left tem­poro-pari­etal cor­tex region, which is known to show marked mod­u­la­tions of alpha pow­er dur­ing audi­to­ry spa­tial atten­tion, tACS (1 mA peak-to-peak ampli­tude) was applied at elec­trode posi­tions TP7 and FC5 over the left hemisphere.

Results: As pre­dict­ed, uni­hemi­spher­ic alpha-tACS rel­a­tive­ly decreased the recall of tar­gets con­tralat­er­al to stim­u­la­tion, but increased recall of ipsi­lat­er­al tar­gets. Impor­tant­ly, this spa­tial pat­tern of results was reversed for gamma-tACS.

Con­clu­sions: Results pro­vide a proof of con­cept that tran­scra­nial­ly stim­u­lat­ed oscil­la­tions can enhance spa­tial atten­tion and facil­i­tate atten­tion­al selec­tion of speech. Fur­ther­more, oppo­site effects of alpha ver­sus gam­ma stim­u­la­tion sup­port the view that states of high alpha are incom­men­su­rate with active neur­al pro­cess­ing as reflect­ed by states of high gamma.

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Auditory Perception Clinical relevance Papers Perception Psychology Publications

New paper out in the ‘Euro­pean Jour­nal of Neu­ro­science’: Tune, Wöst­mann & Obleser

AC post­docs Sarah Tune and Malte Wöst­mann have a new paper out online in the spe­cial issue on Neur­al Oscil­la­tions in the Euro­pean Jour­nal of Neu­ro­science! We are excit­ed to share the results from our first study of the ERC-fund­ed project on lis­ten­ing behav­ior and adap­tive con­trol in mid­dle-aged adults. In this study, we asked whether the fideli­ty of alpha pow­er lat­er­al­iza­tion would serve as a neur­al mark­er of selec­tive audi­to­ry atten­tion in the age­ing lis­ten­er. The results of our mul­ti­vari­ate approach demon­strate that under­stand­ing inter-indi­vid­ual dif­fer­ences is para­mount to under­stand­ing of the role of alpha oscil­la­tions in audi­to­ry atten­tion across age.

Tune, S., Wöst­mann, W., & Obleser, J. (2018) Prob­ing the lim­its of alpha pow­er lat­er­al­i­sa­tion as a neur­al mark­er of selec­tive atten­tion in mid­dle-aged and old­er listeners.

Now avail­able online:

http://onlinelibrary.wiley.com/doi/10.1111/ejn.13862/full/

 

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Adaptive Control Attention Auditory Cortex Auditory Neuroscience Auditory Perception Auditory Speech Processing Degraded Acoustics EEG / MEG Evoked Activity Executive Functions Neural Oscillations Noise-Vocoded Speech Papers Perception Psychology Publications Speech

New paper in press in Cere­bral Cor­tex: Wöst­mann et al. on ignor­ing degrad­ed speech

Audi­to­ry Cognition’s own Malte Wöst­mann is in press in Cere­bral Cor­tex with his lat­est offer­ing on how atten­tion­al con­trol man­i­fests in alpha pow­er changes: Ignor­ing speech can be ben­e­fi­cial (if com­pre­hend­ing speech poten­tial­ly detracts from anoth­er task), and we here show how this change in lis­ten­ing goals turns around the pat­tern of alpha-pow­er changes with chang­ing speech degra­da­tion. (We will update as the paper becomes avail­able online.)

Wöst­mann, M., Lim, S.J., & Obleser, J. (2017). The human neur­al alpha response to speech is a proxy of atten­tion­al con­trol. Cere­bral Cor­tex. In press.

 

Abstract
Human alpha (~10 Hz) oscil­la­to­ry pow­er is a promi­nent neur­al mark­er of cog­ni­tive effort. When lis­ten­ers attempt to process and retain acousti­cal­ly degrad­ed speech, alpha pow­er enhances. It is unclear whether these alpha mod­u­la­tions reflect the degree of acoustic degra­da­tion per se or the degra­da­tion-dri­ven demand to a listener’s atten­tion­al con­trol. Using an irrel­e­vant-speech par­a­digm in elec­troen­cephalog­ra­phy (EEG), the cur­rent exper­i­ment demon­strates that the neur­al alpha response to speech is a sur­pris­ing­ly clear proxy of top-down con­trol, entire­ly dri­ven by the lis­ten­ing goals of attend­ing ver­sus ignor­ing degrad­ed speech. While (n=23) lis­ten­ers retained the ser­i­al order of 9 to-be-recalled dig­its, one to-be-ignored sen­tence was pre­sent­ed. Dis­tractibil­i­ty of the to-be-ignored sen­tence para­met­ri­cal­ly var­ied in acoustic detail (noise-vocod­ing), with more acoustic detail of dis­tract­ing speech increas­ing­ly dis­rupt­ing lis­ten­ers’ ser­i­al mem­o­ry recall. Where pre­vi­ous stud­ies had observed decreas­es in pari­etal and audi­to­ry alpha pow­er with more acoustic detail (of tar­get speech), alpha pow­er here showed the oppo­site pat­tern and increased with more acoustic detail in the speech dis­trac­tor. In sum, the neur­al alpha response reflects almost exclu­sive­ly a listener’s exer­tion of atten­tion­al con­trol, which is deci­sive for whether more acoustic detail facil­i­tates com­pre­hen­sion (of attend­ed speech) or enhances dis­trac­tion (of ignored speech).
Categories
Auditory Cortex Auditory Perception Cross-Modal Integration EEG / MEG Neural Oscillations Perception

New paper out: Plöchl, Gas­ton, Mer­ma­gen, König & Hair­ston, Sci­en­tif­ic Reports

An arti­cle by our new AC group mem­ber Michael Plöchl from his PhD project in Osnabrück has been accept­ed for pub­li­ca­tion in Sci­en­tif­ic Reports. In their study, Plöchl, Gas­ton, Mer­ma­gen, König and Hair­ston demon­strate that “Oscil­la­to­ry activ­i­ty in audi­to­ry cor­tex reflects the per­cep­tu­al lev­el of audio-tac­tile integration”.

oscillatory_activity

Abstract
Cross-modal inter­ac­tions between sen­so­ry chan­nels have been shown to depend on both the spa­tial dis­par­i­ty and the per­cep­tu­al sim­i­lar­i­ty between the pre­sent­ed stim­uli. Here we inves­ti­gate the behav­ioral and neur­al inte­gra­tion of audi­to­ry and tac­tile stim­u­lus pairs at dif­fer­ent lev­els of spa­tial dis­par­i­ty. Addi­tion­al­ly, we mod­u­lat­ed the ampli­tudes of both stim­uli in either a coher­ent or non-coher­ent man­ner. We found that both audi­to­ry and tac­tile local­iza­tion per­for­mance was biased towards the stim­u­lus in the respec­tive oth­er modal­i­ty. This bias lin­ear­ly increas­es with stim­u­lus dis­par­i­ty and is more pro­nounced for coher­ent­ly mod­u­lat­ed stim­u­lus pairs. Analy­ses of elec­troen­cephalo­graph­ic (EEG) activ­i­ty at temporal–cortical sources revealed enhanced event-relat­ed poten­tials (ERPs) as well as decreased alpha and beta pow­er dur­ing bimodal as com­pared to uni­modal stim­u­la­tion. How­ev­er, while the observed ERP dif­fer­ences are sim­i­lar for all stim­u­lus com­bi­na­tions, the extent of oscil­la­to­ry desyn­chro­niza­tion varies with stim­u­lus dis­par­i­ty. More­over, when both stim­uli were sub­jec­tive­ly per­ceived as orig­i­nat­ing from the same direc­tion, the reduc­tion in alpha and beta pow­er was sig­nif­i­cant­ly stronger. These obser­va­tions sug­gest that in the EEG the lev­el of per­cep­tu­al inte­gra­tion is main­ly reflect­ed by changes in ongo­ing oscil­la­to­ry activity.
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 Cortex Auditory Neuroscience Auditory Perception Degraded Acoustics EEG / MEG Evoked Activity Hearing Loss Papers Psychology Publications Speech

New paper in press: Wöst­mann, Schröger, & Obleser in J Cogn Neurosci

Con­grat­u­la­tion to PhD stu­dent Malte Wöst­mann, who – with Erich Schröger and Jonas Obleser – has a new arti­cle in press at the Jour­nal of Cog­ni­tive Neuroscience

Acoustic detail guides atten­tion allo­ca­tion in a selec­tive lis­ten­ing task

forth­com­ing. We will update you accord­ing­ly as the paper comes online. We will share how­ev­er one of Malte’s fig­ures here as a teas­er: The paper utilis­es a very clas­sic com­po­nent of the evoked poten­tial, the con­tin­gent neg­a­tive vari­a­tion (the CNV; or a close rel­a­tive there­of, see the actu­al paper for dis­cus­sion) to study how old­er and younger lis­ten­ers allo­cate their atten­tion­al resources depend­ing on implic­it cues on to-be-expect­ed lis­ten­ing difficulties.

Screen Shot 2014-10-19 at 19.37.43

Ref­er­ences

  • Wöst­mann M1, Schröger E, Obleser J. Acoustic Detail Guides Atten­tion Allo­ca­tion in a Selec­tive Lis­ten­ing Task. J Cogn Neu­rosci. 2014 Nov 12:1–13. PMID: 25390200. [Open with Read]