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Auditory Working Memory EEG / MEG Executive Functions Neural Oscillations Papers Publications

New Paper by Lim, Wöst­mann, & Obleser in Jour­nal of Neuroscience

Can you atten­tive­ly “high­light” audi­to­ry traces in mem­o­ry? If so, what are poten­tial neur­al mech­a­nisms of it?

Sung-Joo Lim’s paper in J Neurosci;

Selec­tive Atten­tion to Audi­to­ry Mem­o­ry Neu­ral­ly Enhances Per­cep­tu­al Precision

is now avail­able online (full text).

Abstract
Selec­tive atten­tion to a task-rel­e­vant stim­u­lus facil­i­tates encod­ing of that stim­u­lus into a work­ing mem­o­ry rep­re­sen­ta­tion. It is less clear whether selec­tive atten­tion also improves the pre­ci­sion of a stim­u­lus already rep­re­sent­ed in mem­o­ry. Here, we inves­ti­gate the behav­ioral and neur­al dynam­ics of selec­tive atten­tion to rep­re­sen­ta­tions in audi­to­ry work­ing mem­o­ry (i.e., audi­to­ry objects) using psy­chophys­i­cal mod­el­ing and mod­el-based analy­sis of elec­troen­cephalo­graph­ic sig­nals. Human lis­ten­ers per­formed a syl­la­ble pitch dis­crim­i­na­tion task where two syl­la­bles served as to-be-encod­ed audi­to­ry objects. Valid (vs neu­tral) retroac­tive cues were pre­sent­ed dur­ing reten­tion to allow lis­ten­ers to selec­tive­ly attend to the to-be-probed audi­to­ry object in mem­o­ry. Behav­ioral­ly, lis­ten­ers rep­re­sent­ed audi­to­ry objects in mem­o­ry more pre­cise­ly (expressed by steep­er slopes of a psy­cho­me­t­ric curve) and made faster per­cep­tu­al deci­sions when valid com­pared to neu­tral retrocues were pre­sent­ed. Neu­ral­ly, valid com­pared to neu­tral retrocues elicit­ed a larg­er fron­to­cen­tral sus­tained neg­a­tiv­i­ty in the evoked poten­tial as well as enhanced pari­etal alpha/low-beta oscil­la­to­ry pow­er (9–18 Hz) dur­ing mem­o­ry reten­tion. Crit­i­cal­ly, indi­vid­ual mag­ni­tudes of alpha oscil­la­to­ry pow­er (7–11 Hz) mod­u­la­tion pre­dict­ed the degree to which valid retrocues ben­e­fit­ted indi­vid­u­als’ behav­ior. Our results indi­cate that selec­tive atten­tion to a spe­cif­ic object in audi­to­ry mem­o­ry does ben­e­fit human per­for­mance not by sim­ply reduc­ing mem­o­ry load, but by active­ly engag­ing com­ple­men­tary neur­al resources to sharp­en the pre­ci­sion of the task-rel­e­vant object in memory.

Con­grats!

Categories
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.
Categories
EEG / MEG Neural Oscillations Neural Phase Papers Publications

Strauß again — in Jour­nal of Neuroscience

Alum­na Dr. Antje Strauß just got anoth­er paper on:

Alpha Phase Deter­mines Suc­cess­ful Lex­i­cal Deci­sion in Noise

by Antje Strauß, Mol­ly Hen­ry, Math­ias Scharinger, and Jonas Obleser

appeared in Jour­nal of Neu­ro­science. Check the abstract below;

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 (EEG) 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 (BI), 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 antiphase in a pres­tim­u­lus time win­dow, and thus suc­cess­ful­ly dis­tin­guished between cor­rect and incor­rect lex­i­cal deci­sions. More­over, alpha-band oscil­la­tions were again approx­i­mate­ly antiphase across par­tic­i­pants for cor­rect ver­sus incor­rect tri­als dur­ing a lat­er peri­s­tim­u­lus time win­dow (∼500 ms) at left-cen­tral elec­trodes. Strik­ing­ly, lex­i­cal deci­sion accu­ra­cy was not pre­dict­ed by either event-relat­ed poten­tials (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 toward char­ac­ter­iz­ing the role of dynam­ic oscil­la­to­ry brain states for high­er cog­ni­tive func­tions, such as spo­ken word recognition.
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]
Categories
Auditory Cortex Auditory Neuroscience Auditory Perception EEG / MEG Evoked Activity Papers Perception Publications

New paper in press: Her­rmann, Schlicht­ing, & Obleser, Jour­nal of Neuroscience

Björn Her­rmann has yet anoth­er paper in press in the Jour­nal of Neuroscience!

Dynam­ic Range Adap­ta­tion to Spec­tral Stim­u­lus Sta­tis­tics in Human Audi­to­ry Cortex

The paper is now avail­able online free of charge, and—funnily enough—appeared right on Jan­u­ary 1, 2014.

Screen Shot 2014-01-02 at 14.38.58

Ref­er­ences

  • Her­rmann B, Schlicht­ing N, Obleser J. Dynam­ic range adap­ta­tion to spec­tral stim­u­lus sta­tis­tics in human audi­to­ry cor­tex. J Neu­rosci. 2014 Jan 1;34(1):327–31. PMID: 24381293. [Open with Read]
Categories
Auditory Cortex Auditory Neuroscience Auditory Perception EEG / MEG Neural Oscillations Neural Phase Papers Perception Publications

New paper in press: Her­rmann, Hen­ry, Grigutsch & Obleser, The Jour­nal of Neu­ro­science [Update]

Oscil­la­to­ry Phase Dynam­ics in Neur­al Entrain­ment Under­pin Illu­so­ry Per­cepts of Time

Nat­ur­al sounds like speech and music inher­ent­ly vary in tem­po over time. Yet, con­tex­tu­al fac­tors such as vari­a­tions in the sound’s loud­ness or pitch influ­ence per­cep­tion of tem­po­ral rate change towards slow­ing down or speed­ing up.

A new MEG study by Björn Her­rmann, Mol­ly Hen­ry, Maren Grigutsch and Jonas Obleser asked for the neur­al oscil­la­to­ry dynam­ics that under­pin con­text-induced illu­sions in tem­po­ral rate change and found illu­so­ry per­cepts to be linked to changes in the neur­al phase pat­terns of entrained oscil­la­tions while the exact fre­quen­cy of the oscil­la­to­ry response was relat­ed to veridi­cal percepts.

The paper is in press and forth­com­ing in The Jour­nal of Neuroscience.

 

Update:

Paper is avail­able online.

Ref­er­ences

  • Her­rmann B, Hen­ry MJ, Grigutsch M, Obleser J. Oscil­la­to­ry phase dynam­ics in neur­al entrain­ment under­pin illu­so­ry per­cepts of time. J Neu­rosci. 2013 Oct 2;33(40):15799–809. PMID: 24089487. [Open with Read]