web analytics
Categories
Auditory Working Memory Degraded Acoustics EEG / MEG Executive Functions Neural Oscillations Papers Publications

[UPDATE] New review paper by Wilsch & Obleser in press: What works in audi­to­ry work­ing memory?

AC alum­na Anna Wilsch (now Uni­ver­si­ty of Old­en­burg) has a new review paper in press in a spe­cial issue on audi­to­ry work­ing mem­o­ry, curat­ed by Jochen Kaiser (Frank­furt) and Michael Brosch (Magde­burg) in “Brain Research”. We pro­vide a review on neur­al oscil­la­to­ry sig­na­tures of (var­i­ous forms of) audi­to­ry short-term memory.

Wilsch, A., Obleser, J. (in press). What works in audi­to­ry work­ing mem­o­ry? A neur­al oscil­la­tions per­spec­tive. Brain Research

Watch out for that spe­cial issue, as it will have an excel­lent ros­ter of col­leagues con­tribut­ing, and we are proud to be part of it.

The abstract is giv­en below.

Abstract
Work­ing mem­o­ry is a lim­it­ed resource: Brains can only main­tain small amounts of sen­so­ry input (mem­o­ry load) over a brief peri­od of time (mem­o­ry decay). The dynam­ics of slow neur­al oscil­la­tions as record­ed using mag­ne­to- and elec­troen­cephalog­ra­phy (M/EEG) pro­vide a win­dow into the neur­al mechan­ics of these lim­i­ta­tions. Espe­cial­ly oscil­la­tions in the alpha range (8–13 Hz) are a sen­si­tive mark­er for mem­o­ry load. More­over, accord­ing to cur­rent mod­els, the resul­tant work­ing mem­o­ry load is deter­mined by the rel­a­tive noise in the neur­al rep­re­sen­ta­tion of main­tained infor­ma­tion. The audi­to­ry domain allows mem­o­ry researchers to apply and test the con­cept of noise quite lit­er­al­ly: Employ­ing degrad­ed stim­u­lus acoustics increas­es mem­o­ry load and, at the same time, al- lows assess­ing the cog­ni­tive resources required to process speech in noise in an eco­log­i­cal­ly valid and clin­i­cal­ly rel­e­vant way. The present review first sum­ma­rizes recent find­ings on neur­al oscil­la­tions, espe­cial­ly alpha pow­er, and how they reflect mem­o­ry load and mem­o­ry decay in audi­to­ry work­ing mem­o­ry. The focus is specif­i­cal­ly on mem­o­ry load result­ing from acoustic degra­da­tion. These find­ings are then con­trast­ed with con­tex­tu­al fac­tors that ben­e­fit neur­al as well as behav­ioral mark­ers of mem­o­ry per­for­mance, by reduc­ing rep­re­sen­ta­tion­al noise. We end on dis­cussing the func­tion­al role of alpha pow­er in audi­to­ry work­ing mem­o­ry and sug­gest exten­sions of the cur­rent method­olog­i­cal toolkit. 
[Update]

Check out the arti­cle online.

Categories
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
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]
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]
Categories
Auditory Perception Auditory Working Memory Events fMRI Neural Oscillations Neural Phase Posters

Come and find us at CNS 2014 in Boston this weekend

The Obleser lab will be pre­sent­ing four posters at this year’s Annu­al Meet­ing of the Cog­ni­tive Neu­ro­science Soci­ety in Boston.

If you hap­pen to be there, come check us out!

A125Hemo­dy­nam­ic sig­na­tures of (mis-)perceiving tem­po­ral change
Her­rmann, Bjoern

C63Tem­po­ral pre­dictabil­i­ty atten­u­ates decay in sen­so­ry memory
Wilsch, Anna

D54Stim­u­lus dis­crim­inabil­i­ty and pre­dic­tive­ness mod­u­late alpha oscil­la­tions in a per­cep­tu­al­ly demand­ing mem­o­ry task
Wöst­mann, Malte

D130Slow acoustic fluc­tu­a­tions entrain low-fre­quen­cy neur­al oscil­la­tions and deter­mine psy­choa­coustic performance
Hen­ry, Molly

Categories
Auditory Working Memory Degraded Acoustics EEG / MEG Executive Functions Neural Oscillations Papers Publications Speech

New Paper out: Wilsch, Hen­ry, Her­rmann et al.

Quite recent­ly Cere­bral Cor­tex published

Alpha Oscil­la­to­ry Dynam­ics Index Tem­po­ral Expec­ta­tion Ben­e­fits in Work­ing Memory

by Anna Wilsch, Mol­ly J Hen­ry, Björn Her­rmann, Burkhard Maess, and Jonas Obleser.

Check the abstract below or fol­low that link to get the full arti­cle.

Abstract
Enhanced alpha pow­er com­pared with a base­line can reflect states of increased cog­ni­tive load, for exam­ple, when lis­ten­ing to speech in noise. Can knowl­edge about “when” to lis­ten (tem­po­ral expec­ta­tions) poten­tial­ly coun­ter­act cog­ni­tive load and con­comi­tant­ly reduce alpha? The cur­rent mag­ne­toen­cephalog­ra­phy (MEG) exper­i­ment induced cog­ni­tive load using an audi­to­ry delayed-match­ing-to-sam­ple task with 2 syl­la­bles S1 and S2 pre­sent­ed in speech-shaped noise. Tem­po­ral expec­ta­tion about the occur­rence of S1 was manip­u­lat­ed in 3 dif­fer­ent cue con­di­tions: “Neu­tral” (unin­for­ma­tive about forepe­ri­od), “ear­ly-cued” (short forepe­ri­od), and “late-cued” (long forepe­ri­od). Alpha pow­er through­out the tri­al was high­est when the cue was unin­for­ma­tive about the onset time of S1 (neu­tral) and low­est for the late-cued con­di­tion. This alpha-reduc­ing effect of late com­pared with neu­tral cues was most evi­dent dur­ing mem­o­ry reten­tion in noise and orig­i­nat­ed pri­mar­i­ly in the right insu­la. More­over, indi­vid­ual alpha effects dur­ing reten­tion account­ed best for observed indi­vid­ual per­for­mance dif­fer­ences between late-cued and neu­tral con­di­tions, indi­cat­ing a trade­off between allo­ca­tion of neur­al resources and the ben­e­fits drawn from tem­po­ral cues. Over­all, the results indi­cate that tem­po­ral expec­ta­tions can facil­i­tate the encod­ing of speech in noise, and con­comi­tant­ly reduce neur­al mark­ers of cog­ni­tive load.

Ref­er­ences

  • Wilsch A, Hen­ry MJ, Her­rmann B, Maess B, Obleser J. Alpha Oscil­la­to­ry Dynam­ics Index Tem­po­ral Expec­ta­tion Ben­e­fits in Work­ing Mem­o­ry. Cereb Cor­tex. 2014 Jan 31. PMID: 24488943. [Open with Read]
Categories
Editorial Notes Events Media Publications

SNAP sum­ma­ry and impressions

The SNAP work­shop (Sig­nal and Noise along the Audi­to­ry Path­way) is behind us.

It is safe to say that it has been a great suc­cess. We will care­ful­ly look into the eval­u­a­tion forms you pro­vid­ed, and we will inform here in due course whether and when a 2nd SNAP (poten­tial­ly 2015) is in the making.

Let us thank all of you who made SNAP hap­pen. It turned a fun and suc­cess­ful sci­en­tif­ic year 2013 into an even greater one. Thank you! We hope to see you soon again, somewhere.

Now, here are some impres­sions of SNAP 2013:

P.S. Here you find Jonas’ clos­ing sum­ma­ry notes:

SNAP 2013 ad hoc sum­ma­ry — Jonas Obleser