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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:

Back­ground: Spa­tial 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.

Categories
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/

 

Categories
Adaptive Control Attention Auditory Working Memory Clinical relevance Executive Functions fMRI Papers Psychology Publications Uncategorized

New paper in press in ‘Neu­roim­age’: Alavash, Lim, et al

Oble­ser­lab post­doc Mohsen Alavash and Oble­ser­lab Alum­na Sung-Joo Lim are in press at Neu­roim­age!

They argue with data from a place­bo-con­trolled dopamin­er­gic inter­ven­tion study that BOLD sig­nal vari­abil­i­ty and the func­tion­al con­nec­tome are sur­pris­ing­ly clear­ly affect­ed by L‑Dopa, and (ii) that the degree of change in these met­rics can explain the degree to which indi­vid­u­als will prof­it from L‑DOPA in per­form­ing the chal­leng­ing lis­ten­ing task (while oth­ers dont; Preprint here ).

Alavash, M., Lim, S.J., Thiel, C., Sehm, B., Deser­no, L., & Obleser, J. (2018) Dopamin­er­gic mod­u­la­tion of hemo­dy­nam­ic sig­nal vari­abil­i­ty and the func­tion­al con­nec­tome dur­ing cog­ni­tive per­for­mance. Neu­roim­age. In press.

— Thanks also and in par­tic­u­lar to our col­leagues Chris­tiane Thiel of Old­en­burg, and Bern­hard Sehm and Lorenz Deser­no of Leipzig, who helped us made this large-scale L‑DOPA project happen!

 

 

Categories
Auditory Cortex Auditory Neuroscience Brain stimulation Clinical relevance Degraded Acoustics Hearing Loss Neural Oscillations Neural Phase Papers Psychology Speech

New paper in press with the Old­en­burg brain-stim­u­la­tion crew!

AC alum­na Anna Wilsch has a new paper in press in Neu­roim­age, with Toralf Neul­ing, Jonas Obleser, and Christoph Her­rmann: “Tran­scra­nial alter­nat­ing cur­rent stim­u­la­tion with speech envelopes mod­u­lates speech com­pre­hen­sion”. In this proof-of-concept–like paper, we demon­strate that using the speech enve­lope as a “pilot sig­nal” for elec­tri­cal­ly stim­u­lat­ing the human brain, while a lis­ten­er tries to com­pre­hend that speech sig­nal buried in noise, does mod­u­late the listener’s speech–in–noise com­pre­hen­sion abilities.

The Preprint is here, … 

… while the abstract goes like this:
Cor­ti­cal entrain­ment of the audi­to­ry cor­tex to the broad­band tem­po­ral enve­lope of a speech sig­nal is cru­cial for speech com­pre­hen­sion. Entrain­ment results in phas­es of high and low neur­al excitabil­i­ty, which struc­ture and decode the incom­ing speech sig­nal. Entrain­ment to speech is strongest in the theta fre­quen­cy range (4−8 Hz), the aver­age fre­quen­cy of the speech enve­lope. If a speech sig­nal is degrad­ed, entrain­ment to the speech enve­lope is weak­er and speech intel­li­gi­bil­i­ty declines. Besides per­cep­tu­al­ly evoked cor­ti­cal entrain­ment, tran­scra­nial alter­nat­ing cur­rent stim­u­la­tion (tACS) entrains neur­al oscil­la­tions by apply­ing an elec­tric sig­nal to the brain. Accord­ing­ly, tACS-induced entrain­ment in audi­to­ry cor­tex has been shown to improve audi­to­ry per­cep­tion. The aim of the cur­rent study was to mod­u­late speech intel­li­gi­bil­i­ty exter­nal­ly by means of tACS such that the elec­tric cur­rent cor­re­sponds to the enve­lope of the pre­sent­ed speech stream (i.e., enve­lope-tACS). Par­tic­i­pants per­formed the Old­en­burg sen­tence test with sen­tences pre­sent­ed in noise in com­bi­na­tion with enve­lope-tACS. Crit­i­cal­ly, tACS was induced at time lags of 0 to 250 ms in 50-ms steps rel­a­tive to sen­tence onset (audi­to­ry stim­uli were simul­ta­ne­ous to or pre­ced­ed tACS). We per­formed sin­gle- sub­ject sinu­soidal, lin­ear, and qua­drat­ic fits to the sen­tence com­pre­hen­sion per­for­mance across the time lags. We could show that the sinu­soidal fit described the mod­u­la­tion of sen­tence com­pre­hen­sion best. Impor­tant­ly, the aver­age fre­quen­cy of the sinu­soidal fit was 5.12 Hz, cor­re­spond­ing to the peaks of the ampli­tude spec­trum of the stim­u­lat­ed envelopes. This find­ing was sup­port­ed by a sig­nif­i­cant 5‑Hz peak in the aver­age pow­er spec­trum of indi­vid­ual per­for­mance time series. Alto­geth­er, enve­lope tACS mod­u­lates intel­li­gi­bil­i­ty of speech in noise, pre­sum­ably by enhanc­ing and dis­rupt­ing (time lag with in- or out-of-phase stim­u­la­tion, respec­tive­ly) cor­ti­cal entrain­ment to the speech enve­lope in audi­to­ry cortex.
Categories
Ageing Auditory Neuroscience EEG / MEG Papers Publications

New paper online by Waschke, Wöst­mann & Obleser

Read all about neur­al irreg­u­lar­i­ty in aging brains and how it relates to per­cep­tu­al deci­sions: New paper by PhD stu­dent Leo Waschke. 

Now avail­able online:
https://goo.gl/F4dFfe

Abstract

Sen­so­ry rep­re­sen­ta­tions, and thus human per­cepts, of the phys­i­cal world are sus­cep­ti­ble to fluc­tu­a­tions in brain state or “neur­al irreg­u­lar­i­ty”. Fur­ther­more, aging brains dis­play altered lev­els of neur­al irreg­u­lar­i­ty. We here show that a sin­gle, with­in-tri­al, infor­ma­tion-the­o­ret­ic mea­sure (weight­ed per­mu­ta­tion entropy) cap­tures neur­al irreg­u­lar­i­ty in the human elec­troen­cephalo­gram as a proxy for both, trait-like dif­fer­ences between indi­vid­u­als of vary­ing age, and state-like fluc­tu­a­tions that bias per­cep­tu­al deci­sions. First, the over­all lev­el of neur­al irreg­u­lar­i­ty increased with par­tic­i­pants’ age, par­al­leled by a decrease in vari­abil­i­ty over time, like­ly index­ing age-relat­ed changes at struc­tur­al and func­tion­al lev­els of brain activ­i­ty. Sec­ond, states of high­er neur­al irreg­u­lar­i­ty were asso­ci­at­ed with opti­mized sen­so­ry encod­ing and a sub­se­quent­ly increased prob­a­bil­i­ty of choos­ing the first of two phys­i­cal­ly iden­ti­cal stim­uli to be high­er in pitch. In sum, neur­al irreg­u­lar­i­ty not only char­ac­ter­izes behav­ioural­ly rel­e­vant brain states, but also can iden­ti­fy trait-like changes that come with age. 

 

 

Categories
Ageing Attention Auditory Cortex Auditory Neuroscience Editorial Notes EEG / MEG Executive Functions Neural Phase Posters

Come see us @ Neu­ro­science 2017 in DC

Will be at the Soci­ety for Neu­ro­science Meet­ing next week in DC? Come find us in the Wednes­day after­noon ses­sion with a bunch of (we think) very cool atten­tion-relat­ed posters (Poster boards UU42–UU46):

804.06. Audi­to­ry atten­tion and pre­dic­tive pro­cess­ing co-mod­u­late speech com­pre­hen­sion in mid­dle-aged adults
*S. TUNE, M. WÖSTMANN, J. OBLESER;

804.05. Implic­it tem­po­ral pre­dictabil­i­ty enhances audi­to­ry pitch-dis­crim­i­na­tion sensitivity
*S. K. HERBST, M. PLÖCHL, A. HERRMANN, J. OBLESER;

804.09. Are visu­al and audi­to­ry detec­tion per­for­mance dri­ven by a supramodal atten­tion­al rhythm?
*M. PLOECHL, S. KASTNER, I. C. FIEBELKORN, J. OBLESER;

804.08. Spa­tio-tem­po­ral expec­ta­tions exert dif­fer­en­tial effects on visu­al and audi­to­ry discrimination
*A. WILSCH, J. OBLESER, C. E. SCHROEDER, C. S. HERRMANN, S. HAEGENS

804.07. Tran­scra­nial 10-Hz stim­u­la­tion but also eye clo­sure mod­u­late audi­to­ry attention
*M. WÖSTMANN, L.-M. SCHMITT, J. VOSSKUHL, C. S. HERRMANN, J. OBLESER

Categories
Attention Auditory Neuroscience EEG / MEG Evoked Activity Neural Oscillations Neural Phase Papers Perception Psychology Uncategorized

New paper in Plos Biol­o­gy: Com­ment by Obleser, Hen­ry, & Lakatos

My col­leagues and col­lab­o­ra­tor Peter Lakatos and Mol­ly Hen­ry and I took to our desks and Mat­lab con­soles, when Assaf Bres­ka and Leon Deouell came out ear­li­er this year with their paper in Plos Biology.

We had a few things to say about what we then per­ceived as a rather pes­simistic assess­ment of neur­al entrain­ment. How­ev­er, since then a great and quite fru­ti­ful dis­cus­sion has emerged, now pub­lished in Plos Biology:

Obleser J, Hen­ry, MJ, & Lakatos, P. What do we talk about when we talk about rhythm?, Plos Biol­o­gy 2017

Mean­while, Bres­ka and Deouell added some more behav­iour­al data and replied to us (now also pub­lished).

— Enjoy!

 

Categories
Events Probandensuche Publications

Audi­to­ry cog­ni­tion newsletter

Come and see our very first audi­to­ry cog­ni­tion newslet­ter. From now on we want to present impres­sions of our lat­est work and results twice a year. In the inter­view sec­tion you also have the chance to learn more about our members. 

Please note: As the newslet­ter also reach­es our par­tic­i­pants it is writ­ten in german.