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Tag: Herrmann

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EEG / MEG Neural Oscillations Papers Publications

New paper by Hen­ry, Her­rmann, & Obleser in Jour­nal of Neuroscience

For­mer Oble­ser­lab post­doc Mol­ly Hen­ry with Björn Her­rmann and Jonas Obleser has a new pub­li­ca­tion in press at Jour­nal of Neuroscience.

Neur­al microstates gov­ern per­cep­tion of audi­to­ry input with­out rhyth­mic structure

by Hen­ry, MJ, Her­mann, B, Obleser, J (in press). J Neurosci.

In devi­a­tion from Molly’s for­mer par­a­digms, we here aimed at bet­ter under­stand­ing the role of oscil­la­to­ry (as well as non-oscil­la­to­ry) slow neur­al activ­i­ty in shap­ing audi­to­ry per­cep­tion when the stim­u­lus is devoid of any rhyth­mic structure.

For a change, the sig­nif­i­cance state­ment and a teas­er fig­ure are shown below.

fluctuation

Abstract
Our abil­i­ty to hear faint sounds fluc­tu­ates togeth­er with slow brain activ­i­ty that syn­chro­nizes with envi­ron­men­tal rhythms. How­ev­er, it is so far not known how brain activ­i­ty at dif­fer­ent time scales might inter­act to influ­ence per­cep­tion when there is no rhythm with which brain activ­i­ty can syn­chro­nize. Here, we used elec­troen­cephalog­ra­phy (EEG) to mea­sure brain activ­i­ty while par­tic­i­pants lis­tened for short silences that inter­rupt­ed ongo­ing noise. We exam­ined brain activ­i­ty in three dif­fer­ent fre­quen­cy bands: delta, theta, and alpha. Par­tic­i­pants’ abil­i­ty to detect gaps depend­ed on dif­fer­ent num­bers of fre­quen­cy bands — some­times one, two, or three — at dif­fer­ent times. Changes in the num­ber of fre­quen­cy bands that pre­dict per­cep­tion are a hall­mark of a com­plex neur­al system.
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Editorial Notes Events Posters Publications

See you at SfN

Soci­ety for Neu­ro­science 2015 is com­ing up. Please come and check out our stuff! Also, Jonas will be chair­ing the sym­po­sium on cor­ti­cal encod­ing of com­plex sound (with talks by for­mer PhD stu­dent Julia Erb and for­mer Post­doc Björn Her­rmann) on tues­day morning.

Posters by the Obleser lab:

Tues­day morn­ing Session:
FIEDLER et al., In-ear-EEG …, Board M46
WILSCH et al., Cor­ti­ca pat­terns of alpha pow­er …, Board Y1
Wednes­day after­noon Session:
LIM et al., Evoked respons­es and alpha oscil­la­tions …, Board BB37

See you there.

 

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]
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Papers Publications

Sen­si­tiv­i­ty of rat infe­ri­or col­licu­lus neu­rons to fre­quen­cy dis­tri­b­u­tions by Her­rmann et al.

New paper in press by AC Alum­ni Björn Her­rman in col­lab­o­ra­tion with Ed Bartlett and col­leagues from Pur­due Uni­ver­si­ty on stim­u­lus-sta­tis­ti­cal and stim­u­lus-spe­cif­ic adap­ta­tion in the rat infe­ri­or col­licu­lus that will appear soon in the Jour­nal of Neurophysiology.

Sen­si­tiv­i­ty of rat infe­ri­or col­licu­lus neu­rons to fre­quen­cy distributions

Abstract
Stim­u­lus-spe­cif­ic adap­ta­tion refers to a neur­al response reduc­tion to a repeat­ed stim­u­lus that does not gen­er­al­ize to oth­er stim­uli. How­ev­er, stim­u­lus-spe­cif­ic adap­ta­tion appears be influ­enced by addi­tion­al fac­tors. For exam­ple, the sta­tis­ti­cal dis­tri­b­u­tion of tone fre­quen­cies has recent­ly been shown to dynam­i­cal­ly alter stim­u­lus-spe­cif­ic adap­ta­tion in human audi­to­ry cor­tex. The cur­rent study inves­ti­gat­ed whether sta­tis­ti­cal stim­u­lus dis­tri­b­u­tions also affect stim­u­lus-spe­cif­ic adap­ta­tion at an ear­li­er stage of the audi­to­ry hier­ar­chy. Neur­al spik­ing activ­i­ty and local field poten­tials were record­ed from infe­ri­or col­licu­lus neu­rons of rats while tones were pre­sent­ed in odd­ball sequences that formed two dif­fer­ent sta­tis­ti­cal con­texts. Each sequence con­sist­ed of a repeat­ed­ly pre­sent­ed tone (stan­dard) and three rare deviants of dif­fer­ent mag­ni­tudes (small, mod­er­ate, large spec­tral change). The crit­i­cal manip­u­la­tion was the rel­a­tive prob­a­bil­i­ty with which large spec­tral changes occurred. In one con­text, the prob­a­bil­i­ty was high (rel­a­tive to all deviants) while it was low in the oth­er con­text. We observed larg­er respons­es for deviants com­pared to stan­dards, con­firm­ing pre­vi­ous reports of increased response adap­ta­tion for fre­quent­ly pre­sent­ed tones. Impor­tant­ly, the sta­tis­ti­cal con­text in which tones were pre­sent­ed strong­ly mod­u­lat­ed stim­u­lus-spe­cif­ic adap­ta­tion. Phys­i­cal­ly and prob­a­bilis­ti­cal­ly iden­ti­cal stim­uli (mod­er­ate deviants) in the two sta­tis­ti­cal con­texts elicit­ed dif­fer­ent respons­es mag­ni­tudes con­sis­tent with neur­al gain changes and thus neur­al sen­si­tiv­i­ty adjust­ments induced by the spec­tral range of a stim­u­lus dis­tri­b­u­tion. The data show that already at the lev­el of the infe­ri­or col­licu­lus stim­u­lus-spe­cif­ic adap­ta­tion is dynam­i­cal­ly altered by the sta­tis­ti­cal con­text in which stim­uli occur.

Ref­er­ences

  • Her­rmann B1, Parthasarathy A2, Han EX, Obleser J3, Bartlett EL2. Sen­si­tiv­i­ty of rat infe­ri­or col­licu­lus neu­rons to fre­quen­cy dis­tri­b­u­tions. J Neu­ro­phys­i­ol. 2015 Sep 9:jn. PMID: 26354316. [Open with Read]
Categories
EEG / MEG Neural Oscillations Neural Phase Papers Publications

New Paper out in Psy­chophys­i­ol­o­gy — Wilsch et al.

A new paper on

Slow-delta phase con­cen­tra­tion marks improved tem­po­ral expec­ta­tions based on the pas­sage of time

by AC PhD Anna Wilsch, alum­ni post­docs Mol­ly Hen­ry & Björn Her­rmann, AC head Jonas Obleser along with Burkhard Maess appeared in Psychophysiology.

Check the online source, or take a quick look on the abstract below.

Abstract
Tem­po­ral expec­ta­tions enhance neur­al encod­ing pre­ci­sion, reflect­ed in opti­mized align­ment of slow neur­al oscil­la­to­ry phase, and facil­i­tate sub­se­quent stim­u­lus pro­cess­ing. If an even­t’s exact occur­rence time is unknown, tem­po­ral expec­ta­tions arise sole­ly from the pas­sage of time. Here, we show that this spe­cif­ic type of tem­po­ral expec­ta­tion is also reflect­ed in neur­al phase orga­ni­za­tion. While under­go­ing mag­ne­toen­cephalog­ra­phy, par­tic­i­pants per­formed an audi­to­ry-delayed match­ing-to-sam­ple task with two syl­la­bles (S1, S2). Crit­i­cal­ly, S1-onset time var­ied in the 0.6–1.8‑s (i.e., 0.6−1.7 Hz) range. Increas­ing S1-onset times led to increased slow-delta (0.6−0.9 Hz) phase coher­ence over right fron­totem­po­ral sen­sors dur­ing S1 encod­ing. More­over, indi­vid­u­als with high­er slow-delta coher­ence showed decreased alpha pow­er (8−13 Hz) dur­ing sub­se­quent mem­o­ry reten­tion. In sum, tem­po­ral expec­ta­tions based on the pas­sage of time opti­mize the pre­cise align­ment of neur­al oscil­la­to­ry phase with an expect­ed stimulus.

Ref­er­ences

  • Wilsch A1, Hen­ry MJ, Her­rmann B, Maess B, Obleser J. Slow-delta phase con­cen­tra­tion marks improved tem­po­ral expec­ta­tions based on the pas­sage of time. Psy­chophys­i­ol­o­gy. 2015 Feb 16. PMID: 25684032. [Open with Read]
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Editorial Notes

2015 — Embrac­ing Change in the Obleser Lab

Time flies: The Audi­to­ry Cog­ni­tion group aka The Obleser Lab has just entered its fifth year. We took off prop­er­ly in ear­ly 2011, so this is a good point in time to briefly recap. We have had four excit­ing and very pro­duc­tive years so far, and this fifth year is bring­ing a lot of excit­ing turn-over as well. First, new faces have joined our group:

Dr. Sophie Herb­st a psy­chol­o­gist with keen inter­ests in time per­cep­tion joined us as a post­doc, com­ing from Niko Busch’s lab at the Char­ité Berlin.

Dipl.-Ing. (FH) Lorenz Fiedler joined us to help us build real-time links between EEG and hear­ing aids, as planned in our Volk­swa­gen project.

Sec­ond, a few great tal­ents have moved on with the begin­ning of 2015:

Antje Strauß just received her Dr. rer. nat. (PhD) from the Uni­ver­si­ty of Leipzig and is now at the GIPSA lab, Uni­ver­si­ty of Greno­ble, France.

Dr. Mol­ly Hen­ry and Dr. Björn Her­rmann have both tak­en up new Post­doc­tor­al jobs at the Uni­ver­si­ty of West­ern Ontario, Lon­don, Ontario, CA. They will be work­ing with Jes­si­ca Grahn and Ingrid John­srude, respec­tive­ly.

Dr. Alex Brand­mey­er could not resist a fan­tas­tic offer by Dol­by Sys­tems Inc., San Fran­cis­co to join them as a research scientist.

Ear­li­er in autumn 2014 already, Julia Erb had tak­en up a post­doc posi­tion with Elia Formisano at the Uni­ver­si­ty of Maas­tricht.

… the best of luck and many thanks to all the new AC alumni!

Last­ly, Jonas as head of the group has just been appoint­ed Pro­fes­sor for Research Meth­ods and Sta­tis­tics at the (new­ly-found­ed) Depart­ment of Psy­chol­o­gy, Uni­ver­si­ty of Lübeck, Ger­many.

These great news also imply that the Audi­to­ry Cog­ni­tion group as a whole will, as con­ceived by the Max Planck Soci­ety when pro­vid­ing this five-year start-up fund­ing, slow­ly trans­plant to a new place, name­ly: Lübeck, over the year to come. Watch this space! Yet, the labels “auditorycognition.com” and “obleserlab.com” will sure­ly remain active and move with us.

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
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]