Category: Papers

Categories
EEG / MEG Linguistics Neural Oscillations Papers Publications

New paper out: Dis­so­ci­a­tion of alpha and theta oscil­la­tions Strauß, Kotz, Scharinger, Obleser

We are very hap­py to announce that PhD stu­dent Antje Strauß got her paper

Alpha and theta brain oscil­la­tions index dis­so­cia­ble process­es in spo­ken word recognition

accept­ed at Neu­roIm­age. Con­grat­u­la­tions! Find her paper here.

See the Abstract
Slow neur­al oscil­la­tions (∼ 1–15 Hz) are thought to orches­trate the neur­al process­es of spo­ken lan­guage com­pre­hen­sion. How­ev­er, func­tion­al sub­di­vi­sions with­in this broad range of fre­quen­cies are dis­put­ed, with most stud­ies hypoth­e­siz­ing only about sin­gle fre­quen­cy bands. The present study uti­lizes an estab­lished par­a­digm of spo­ken word recog­ni­tion (lex­i­cal deci­sion) to test the hypoth­e­sis that with­in the slow neur­al oscil­la­to­ry fre­quen­cy range, dis­tinct func­tion­al sig­na­tures and cor­ti­cal net­works can be iden­ti­fied at least for theta- (∼ 3–7 Hz) and alpha-fre­quen­cies (∼ 8–12 Hz). Lis­ten­ers per­formed an audi­to­ry lex­i­cal deci­sion task on a set of items that formed a word–pseudoword con­tin­u­um: rang­ing from (1) real words over (2) ambigu­ous pseu­do­words (devi­at­ing from real words only in one vow­el; com­pa­ra­ble to nat­ur­al mis­pro­nun­ci­a­tions in speech) to (3) pseu­do­words (clear­ly devi­at­ing from real words by ran­dom­ized syl­la­bles). By means of time–frequency analy­sis and spa­tial fil­ter­ing, we observed a dis­so­ci­a­tion into dis­tinct but simul­ta­ne­ous pat­terns of alpha pow­er sup­pres­sion and theta pow­er enhance­ment. Alpha exhib­it­ed a para­met­ric sup­pres­sion as items increas­ing­ly matched real words,in line with low­ered func­tion­al inhi­bi­tion in a left-dom­i­nant lex­i­cal pro­cess­ing net­work for more word-like input. Simul­ta­ne­ous­ly, theta pow­er in a bilat­er­al fron­to-tem­po­ral net­work was selec­tive­ly enhanced for ambigu­ous pseu­do­words only. Thus, enhanced alpha pow­er can neu­ral­ly “gate” lex­i­cal inte­gra­tion, while enhanced theta pow­er might index func­tion­al­ly more spe­cif­ic ambi­gu­i­ty-res­o­lu­tion process­es. To this end, a joint analy­sis of both fre­quen­cy bands pro­vides neur­al evi­dence for par­al­lel process­es in achiev­ing spo­ken word recognition.

Ref­er­ences

  • Strauβ A1, Kotz SA2, Scharinger M3, Obleser J3. Alpha and theta brain oscil­la­tions index dis­so­cia­ble process­es in spo­ken word recog­ni­tion. Neu­roim­age. 2014 Apr 18. PMID: 24747736. [Open with Read]
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
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
Ageing Auditory Neuroscience Auditory Speech Processing Clinical relevance Degraded Acoustics Executive Functions fMRI Hearing Loss Noise-Vocoded Speech Papers Publications Speech

New paper in press: Erb & Obleser, Fron­tiers in Sys­tems Neuroscience

Julia Erb just got accept­ed the third study of her PhD project,

Upreg­u­la­tion of cog­ni­tive con­trol net­works in old­er adults’ speech comprehension

It will appear in Fron­tiers in Sys­tems Neu­ro­science soon.

The data are an exten­sion (in old­er adults) of Julia’s Jour­nal of Neu­ro­science paper ear­li­er this year.

Ref­er­ences

  • Erb J, Obleser J. Upreg­u­la­tion of cog­ni­tive con­trol net­works in old­er adults’ speech com­pre­hen­sion. Front Syst Neu­rosci. 2013 Dec 24;7:116. PMID: 24399939. [Open with Read]
Categories
Auditory Cortex Auditory Neuroscience Auditory Perception Auditory Speech Processing EEG / MEG Neural Oscillations Neural Phase Papers Publications

New paper in press: Hen­ry & Obleser, PLOS ONE [Update]

Watch this space and the PLOS ONE web­site for a forth­com­ing arti­cle by Mol­ly Hen­ry and me;

Dis­so­cia­ble neur­al response sig­na­tures for slow ampli­tude and fre­quen­cy mod­u­la­tion in human audi­to­ry cortex

Hark­ing back at what we had argued ini­tial­ly in our 2012 Fron­tiers op’ed piece (togeth­er with Björn Her­rmann), Mol­ly presents neat evi­dence for dis­so­cia­ble cor­ti­cal sig­na­tures of slow ampli­tude ver­sus fre­quen­cy mod­u­la­tion. These cor­ti­cal sig­na­tures poten­tial­ly pro­vide an effi­cient means to dis­sect simul­ta­ne­ous­ly com­mu­ni­cat­ed slow tem­po­ral and spec­tral infor­ma­tion in acoustic com­mu­ni­ca­tion signals.

[Update]

Paper is avail­able here.

Ref­er­ences

  • Hen­ry MJ, Obleser J. Dis­so­cia­ble neur­al response sig­na­tures for slow ampli­tude and fre­quen­cy mod­u­la­tion in human audi­to­ry cor­tex. PLoS One. 2013 Oct 29;8(10):e78758. PMID: 24205309. [Open with Read]
Categories
Auditory Neuroscience Auditory Perception Degraded Acoustics Executive Functions Papers Publications

Lis­ten­ing: The strat­e­gy mat­ters [Update]

In press on Neuropsychologia

Thal­a­m­ic and pari­etal brain mor­phol­o­gy pre­dicts audi­to­ry cat­e­go­ry learning

figure_mat

Cat­e­go­riz­ing sounds is vital for adap­tive human behav­ior. Accord­ing­ly, chang­ing lis­ten­ing sit­u­a­tions (exter­nal noise, but also periph­er­al hear­ing loss in aging) require lis­ten­ers to flex­i­bly adjust their cat­e­go­riza­tion strate­gies, e.g., switch amongst avail­able acoustic cues. How­ev­er, lis­ten­ers dif­fer con­sid­er­ably in these adap­tive capa­bil­i­ties. For this rea­son, we employed vox­el-based mor­phom­e­try (VBM) in our study (Neu­ropsy­cholo­gia, In press), in order to assess the degree to which indi­vid­ual brain mor­phol­o­gy is pre­dic­tive of such adap­tive lis­ten­ing behavior.

Con­tin­ue read­ing “Lis­ten­ing: The strat­e­gy mat­ters [Update]”

Ref­er­ences

  • Scharinger M1, Hen­ry MJ2, Erb J2, Mey­er L3, Obleser J2. Thal­a­m­ic and pari­etal brain mor­phol­o­gy pre­dicts audi­to­ry cat­e­go­ry learn­ing. Neu­ropsy­cholo­gia. 2014 Jan;53:75–83. PMID: 24035788. [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]
Categories
Auditory Neuroscience Auditory Perception Auditory Working Memory Executive Functions fMRI Papers Perception Publications

New paper has been pub­lished in Cere­bral Cor­tex by Hen­ry, Her­rmann, & Obleser

When we lis­ten to sounds like speech and music, we have to make sense of dif­fer­ent acoustic fea­tures that vary simul­ta­ne­ous­ly along mul­ti­ple time scales. This means that we, as lis­ten­ers, have to selec­tive­ly attend to, but at the same time selec­tive­ly ignore, sep­a­rate but inter­twined fea­tures of a stimulus.

Brain regions associated with selective attending to and selective ignoring of temporal stimulus features.
Brain regions asso­ci­at­ed with selec­tive attend­ing to and selec­tive ignor­ing of tem­po­ral stim­u­lus fea­tures. (more)

A new­ly pub­lished fMRI study by Mol­ly Hen­ry, Björn Her­rmann, and Jonas Obleser found a net­work of brain regions that respond­ed oppo­site­ly to iden­ti­cal stim­u­lus char­ac­ter­is­tics depend­ing on whether they were rel­e­vant or irrel­e­vant, even when both stim­u­lus fea­tures involved atten­tion to time and tem­po­ral features.

You can check out the arti­cle here:

http://cercor.oxfordjournals.org/content/early/2013/08/23/cercor.bht240.full

Ref­er­ences

  • Hen­ry MJ, Her­rmann B, Obleser J. Selec­tive Atten­tion to Tem­po­ral Fea­tures on Nest­ed Time Scales. Cereb Cor­tex. 2013 Aug 26. PMID: 23978652. [Open with Read]