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Category: Psychology

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Adaptive Control Ageing Attention Auditory Cortex Auditory Neuroscience Auditory Speech Processing Executive Functions fMRI Papers Psychology Uncategorized

New paper in PNAS by Alavash, Tune, Obleser

How brain areas com­mu­ni­cate shapes human com­mu­ni­ca­tion: The hear­ing regions in your brain form new alliances as you try to lis­ten at the cock­tail party

Oble­ser­lab Post­docs Mohsen Alavash and Sarah Tune rock out an intri­cate graph-the­o­ret­i­cal account of mod­u­lar recon­fig­u­ra­tions in chal­leng­ing lis­ten­ing sit­u­a­tions, and how these pre­dict indi­vid­u­als’ lis­ten­ing success.

Avail­able online now in PNAS! (Also, our uni is cur­rent­ly fea­tur­ing a Ger­man-lan­guage press release on it, as well as an Eng­lish-lan­guage ver­sion)

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Attention Auditory Cortex Auditory Neuroscience EEG / MEG Papers Perception Psychology Publications

New paper in Neu­roim­age by Fiedler et al.: Track­ing ignored speech matters

Lis­ten­ing requires selec­tive neur­al pro­cess­ing of the incom­ing sound mix­ture, which in humans is borne out by a sur­pris­ing­ly clean rep­re­sen­ta­tion of attend­ed-only speech in audi­to­ry cor­tex. How this neur­al selec­tiv­i­ty is achieved even at neg­a­tive sig­nal-to-noise ratios (SNR) remains unclear. We show that, under such con­di­tions, a late cor­ti­cal rep­re­sen­ta­tion (i.e., neur­al track­ing) of the ignored acoustic sig­nal is key to suc­cess­ful sep­a­ra­tion of attend­ed and dis­tract­ing talk­ers (i.e., neur­al selec­tiv­i­ty). We record­ed and mod­eled the elec­troen­cephalo­graph­ic response of 18 par­tic­i­pants who attend­ed to one of two simul­ta­ne­ous­ly pre­sent­ed sto­ries, while the SNR between the two talk­ers var­ied dynam­i­cal­ly between +6 and −6 dB. The neur­al track­ing showed an increas­ing ear­ly-to-late atten­tion-biased selec­tiv­i­ty. Impor­tant­ly, acousti­cal­ly dom­i­nant (i.e., loud­er) ignored talk­ers were tracked neu­ral­ly by late involve­ment of fron­to-pari­etal regions, which con­tributed to enhanced neur­al selec­tiv­i­ty. This neur­al selec­tiv­i­ty, by way of rep­re­sent­ing the ignored talk­er, pos­es a mech­a­nis­tic neur­al account of atten­tion under real-life acoustic conditions.

The paper is avail­able here.

Categories
Adaptive Control Auditory Cortex Auditory Neuroscience Auditory Working Memory Neural Oscillations Papers Perception Psychology Uncategorized

New paper in The Jour­nal of Neu­ro­science: Wilsch et al.., Tem­po­ral expec­ta­tion mod­u­lates the cor­ti­cal dynam­ics of short-term memory

Con­grat­u­la­tions to Oble­ser­lab alum­na Anna Wilsch, who is – for now – leav­ing acad­e­mia on a true high with her lat­est offer­ing on how tem­po­ral expec­ta­tions (“fore­knowl­edge” about when some­thing is to hap­pen) shape the neur­al make-up of memory!

Record­ed while the Oble­ser­lab was still in Leipzig at the Max Planck, and analysed with great input from our co-authors Mol­ly Hen­ry, Björn Her­rmann as well as Christoph Her­rmann (Old­en­burg), Anna used Mag­ne­toen­cephalog­ra­phy in an intri­cate but ulti­mate­ly very sim­ple sen­so­ry-mem­o­ry paradigm.

 

While sen­so­ry mem­o­ries of the phys­i­cal world fade quick­ly, Anna here shows that this decay of short-term mem­o­ry can be coun­ter­act­ed by tem­po­ral expectation.

Notably, spa­tial­ly dis­trib­uted cor­ti­cal pat­terns of alpha (8−−13 Hz) pow­er showed oppos­ing effects in audi­to­ry vs. visu­al sen­so­ry cor­tices. More­over, alpha-tuned con­nec­tiv­i­ty changes with­in supramodal atten­tion net­works reflect the allo­ca­tion of neur­al resources as short-term mem­o­ry rep­re­sen­ta­tions fade.

— to be updat­ed as the paper will become avail­able online –

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Auditory Cortex Brain stimulation Papers Psychology Publications

New paper in press at eNeu­ro: Herb­st, Fiedler and Obleser on track­ing tem­po­ral haz­ard in the human EEG

Here, we show that human par­tic­i­pants use implic­it mod­u­la­tions of  tem­po­ral haz­ard, the prob­a­bil­i­ty of an item to occur at a cer­tain moment in time giv­en it has not yet occurred, when per­form­ing a pitch dis­crim­i­na­tion task. Using an encod­ing mod­el approach allows us to iso­late the track­ing of  tem­po­ral haz­ard by the time domain EEG sig­nal, notably by the sup­ple­men­tary motor area, a region known for its impli­ca­tion in timing.

The paper is avail­able as preprint:

https://www.biorxiv.org/content/early/2017/12/14/233551

Herb­st SK, Fiedler L & Obleser J (2018), Track­ing tem­po­ral haz­ard in the human elec­troen­cephalo­gram using a for­ward encod­ing mod­el. eNeu­ro (in press). 

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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
Ageing Auditory Cortex Events Perception Psychology

Sym­po­sium at PuG 2018

Dur­ing the upcom­ing meet­ing of “Psy­chol­o­gy and the Brain 2018”, PhD stu­dent Leo Waschke will be host­ing a sym­po­sium on states and traits of neur­al activ­i­ty and their func­tion­al rel­e­vance for per­cep­tion and age­ing. Togeth­er with Lin­da Geerligs (Don­ders Insti­tute, NL), Marieke Schölvinck (ESI, Frank­furt) and Niels Kloost­er­man (MPIB, Berlin) he will be address­ing fluc­tu­a­tions in brain activ­i­ty on a host of timescales from mil­lisec­onds to min­utes. We are look­ing for­ward to meet­ing you in Giessen.

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!