Category: Linguistics

Categories
Ageing Attention Auditory Neuroscience Auditory Perception Auditory Speech Processing EEG / MEG Executive Functions fMRI Grants Hearing Loss Linguistics Neural dynamics Perception Semantics Uncategorized

A grant dou­ble to celebrate

We are hon­oured and delight­ed that the Deutsche Forschungs­ge­mein­schaft has deemed two of our recent appli­ca­tions wor­thy of fund­ing: The two senior researchers in the  lab, Sarah Tune and Malte Wöst­mann, have both been award­ed three-year grant fund­ing for their new projects. Congratulations!

In her 3‑year, 360‑K€ project “How per­cep­tu­al infer­ence changes with age: Behav­iour­al and brain dynam­ics of speech per­cep­tion”, Sarah Tune will explore the role of per­cep­tu­al pri­ors in speech per­cep­tion in the age­ing lis­ten­er. She will main­ly use neur­al and per­cep­tu­al mod­el­ling and func­tion­al neuroimaging.

In his 3‑year, 270‑K€ project “Inves­ti­ga­tion of cap­ture and sup­pres­sion in audi­to­ry atten­tion”, Malte Wöst­mann will con­tin­ue and refine his suc­cess­ful research endeav­our into dis­so­ci­at­ing the role of sup­pres­sive mech­a­nisms in the lis­ten­ing mind and brain, main­ly using EEG and behav­iour­al modelling.

Both of them will soon adver­tise posts for PhD can­di­dates to join us, accord­ing­ly, and to work on these excit­ing projects with Sarah and Malte and the rest of the Oble­ser­lab team

 

Categories
Auditory Neuroscience Auditory Speech Processing fMRI Linguistics Papers Perception Psychology Semantics Speech Uncategorized

New paper in Sci­ence Advances by Schmitt et al.

Very excit­ed to announce that for­mer Obleser lab PhD stu­dent Lea-Maria Schmitt with her co-authors *) is now out in the Jour­nal Sci­ence Advances with her new work, fus­ing artif­i­cal neur­al net­works and func­tion­al MRI data, on timescales of pre­dic­tion in nat­ur­al lan­guage comprehension:

“Pre­dict­ing speech from a cor­ti­cal hier­ar­chy of event-based time scales”

*) Lea-Maria Schmitt, Julia Erb, Sarah Tune, and Jonas Obleser from the Obleser lab / Lübeck side, and our col­lab­o­ra­tors Anna Rysop and Gesa Hartwigsen from Gesa’s Lise Meit­ner group at the Max Planck Insti­tute in Leipzig. This research was made pos­si­ble by the ERC and the DFG.

 

Categories
Executive Functions Grants Gyrus Angularis Linguistics

New grant award­ed by the Deutsche Forschungs­ge­mein­schaft (DFG)

Categories
Auditory Speech Processing EEG / MEG Linguistics Papers Publications Speech

New edi­to­r­i­al in “Brain & Lan­guage”: Re-vis­it­ing the elec­tro­phys­i­ol­o­gy of language

I had the hon­our of guest-edit­ing a spe­cial issue for the clas­sic jour­nal “Brain and Lan­guage” and have thus con­tributed a brief edi­to­r­i­al (now online) to this issue. The spe­cial issue re-vis­its old themes and new leads in the elec­tro­phys­i­ol­o­gy of speech, lan­guage, and its precursors.

UPDATE: The full spe­cial issue appeared in Sep­tem­ber 2015 and all arti­cles are now acces­si­ble and citable. Thanks for your kind attention!

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
fMRI Linguistics Papers Publications Speech

New paper in Neu­roIm­age by Scharinger, Hen­ry, & Obleser [UPDATED]

A new paper is about to appear in Neu­roim­age on

Acoustic cue selec­tion and dis­crim­i­na­tion under degra­da­tion: Dif­fer­en­tial con­tri­bu­tions of the infe­ri­or pari­etal and pos­te­ri­or tem­po­ral cortices

by Math­ias Scharinger, Mol­ly J. Hen­ry, Jonas Obleser

Abstract
Cat­e­go­riz­ing sounds is vital for adap­tive human behav­ior. Accord­ing­ly, chang­ing lis­ten­ing sit­u­a­tions (exter­nal noise or periph­er­al hear­ing loss in aging) that may be accom­pa­nied by changes in dis­crim­inabil­i­ty, require lis­ten­ers to flex­i­bly adjust their cat­e­go­riza­tion strate­gies, some­times by changes in uti­liz­ing avail­able acoustic cues.
In this func­tion­al Mag­net­ic Res­o­nance Imag­ing (fMRI) study, we inves­ti­gate the cat­e­go­riza­tion of nov­el, non-speech audi­to­ry stim­uli that var­ied in over­all dis­crim­inabil­i­ty. More­over, we manip­u­late the rel­a­tive infor­ma­tive­ness of a dura­tion ver­sus a spec­tral-peak cue by adding spec­tral degra­da­tion in the mid­dle of the exper­i­ment. The results demon­strate dif­fer­ent roles of tem­po­ral and pari­etal brain areas for audi­to­ry cat­e­go­riza­tion: Tem­po­ral cor­tex acti­va­tion, in par­tic­u­lar in pos­te­ri­or parts of the right supe­ri­or tem­po­ral gyrus, scaled with dis­crim­inabil­i­ty, while left pari­etal cor­tex acti­va­tion was asso­ci­at­ed with changes in cue uti­liza­tion after the appli­ca­tion of spec­tral degradation.
This work extends pre­vi­ous research on audi­to­ry cat­e­go­riza­tion. Impor­tant­ly, the involve­ment of the left infe­ri­or pari­etal lob­ule in changes of cue uti­liza­tion sup­ports its role in domain-gen­er­al process­es that sup­port cat­e­go­riza­tion. Fur­ther, the sen­si­tiv­i­ty of the right pos­te­ri­or supe­ri­or tem­po­ral gyrus to stim­u­lus dis­crim­inabil­i­ty adds to pre­vi­ous find­ings regard­ing its role in audi­to­ry processing. 

[UPDATE] Link added.

Ref­er­ences

  • Scharinger M1, Hen­ry MJ2, Obleser J2. Acoustic cue selec­tion and dis­crim­i­na­tion under degra­da­tion: Dif­fer­en­tial con­tri­bu­tions of the infe­ri­or pari­etal and pos­te­ri­or tem­po­ral cor­tices. Neu­roim­age. 2015 Feb 1;106:373–81. PMID: 25481793. [Open with Read]

Categories
Auditory Neuroscience Auditory Perception Auditory Speech Processing Clinical relevance Degraded Acoustics Gyrus Angularis Linguistics Noise-Vocoded Speech Papers Perception Psychology Speech

New paper in press: Hartwigsen, Golombek, & Obleser in Cor­tex [UPDATED]

In a col­lab­o­ra­tion with the Uni­ver­si­ty Clin­ic of Leipzig and Prof Dr Gesa Hartwigsen (now Uni­ver­si­ty of Kiel), a new paper is to appear in “Cor­tex”, in the forth­com­ing spe­cial issue on Pre­dic­tion in Speech and Lan­guage, edit­ed by Alessan­dro Tavano and AC alum­nus Math­ias Scharinger.

Repet­i­tive tran­scra­nial mag­net­ic stim­u­la­tion over left angu­lar gyrus mod­u­lates the pre­dictabil­i­ty gain in degrad­ed speech comprehension

Hartwigsen G, Golombek T, & Obleser J.

See abstract
Increased neur­al activ­i­ty in left angu­lar gyrus (AG) accom­pa­nies suc­cess­ful com­pre­hen­sion of acousti­cal­ly degrad­ed but high­ly pre­dictable sen­tences, as pre­vi­ous func­tion­al imag­ing stud­ies have shown. How­ev­er, it remains unclear whether the left AG is causal­ly rel­e­vant for the com­pre­hen­sion of degrad­ed speech. Here, we applied tran­sient vir­tu­al lesions to either the left AG or supe­ri­or pari­etal lobe (SPL, as a con­trol area) with repet­i­tive tran­scra­nial mag­net­ic stim­u­la­tion (rTMS) while healthy vol­un­teers lis­tened to and repeat­ed sen­tences with high- vs. low-pre­dictable end­ings and dif­fer­ent noise vocod­ing lev­els. We expect­ed that rTMS of AG should selec­tive­ly mod­u­late the pre­dictabil­i­ty gain (i.e., the com­pre­hen­sion ben­e­fit from sen­tences with high-pre­dictable end­ings) at a medi­um degra­da­tion lev­el. We found that rTMS of AG indeed reduced the pre­dictabil­i­ty gain at a medi­um degra­da­tion lev­el of 4‑band noise vocod­ing (rel­a­tive to con­trol rTMS of SPL). In con­trast, the behav­ioral per­tur­ba­tion induced by rTMS reversed with increased sig­nal qual­i­ty. Hence, at 8‑band noise vocod­ing, rTMS over AG vs. SPL increased the over­all pre­dictabil­i­ty gain. Togeth­er, these results show that the degree of the rTMS inter­fer­ence depend­ed joint­ly on sig­nal qual­i­ty and pre­dictabil­i­ty. Our results pro­vide the first causal evi­dence that the left AG is a crit­i­cal node for facil­i­tat­ing speech com­pre­hen­sion in chal­leng­ing lis­ten­ing conditions.

Screen Shot 2014-09-11 at 21.19.17

Check it out soon!

Ref­er­ences

  • Hartwigsen G1, Golombek T2, Obleser J3. Repet­i­tive tran­scra­nial mag­net­ic stim­u­la­tion over left angu­lar gyrus mod­u­lates the pre­dictabil­i­ty gain in degrad­ed speech com­pre­hen­sion. Cor­tex. 2014 Sep 18. PMID: 25444577. [Open with Read]

Categories
Degraded Acoustics EEG / MEG fMRI Linguistics Papers Publications

New paper out: Simul­ta­ne­ous fMRI–EEG in audi­to­ry cat­e­go­riza­tion by Scharinger et al.

Con­grat­u­la­tions to Obleser lab alum­nus Math­ias Scharinger who this week pub­lished our joint work on simul­ta­ne­ous fMRI–EEG in Fron­tiers in Human Neuroscience!

Simul­ta­ne­ous EEG-fMRI brain sig­na­tures of audi­to­ry cue utilization

by Scharinger, Her­rmann, Nier­haus, & Obleser

See abstract
Opti­mal uti­liza­tion of acoustic cues dur­ing audi­to­ry cat­e­go­riza­tion is a vital skill, par­tic­u­lar­ly when infor­ma­tive cues become occlud­ed or degrad­ed. Con­se­quent­ly, the acoustic envi­ron­ment requires flex­i­ble choos­ing and switch­ing amongst avail­able cues. The present study tar­gets the brain func­tions under­ly­ing such changes in cue uti­liza­tion. Par­tic­i­pants per­formed a cat­e­go­riza­tion task with imme­di­ate feed­back on acoustic stim­uli from two cat­e­gories that var­ied in dura­tion and spec­tral prop­er­ties, while we simul­ta­ne­ous­ly record­ed Blood Oxy­gena­tion Lev­el Depen­dent (BOLD) respons­es in fMRI and elec­troen­cephalo­grams (EEGs). In the first half of the exper­i­ment, cat­e­gories could be best dis­crim­i­nat­ed by spec­tral prop­er­ties. Halfway through the exper­i­ment, spec­tral degra­da­tion ren­dered the stim­u­lus dura­tion the more infor­ma­tive cue. Behav­ioral­ly, degra­da­tion decreased the like­li­hood of uti­liz­ing spec­tral cues. Spec­tral­ly degrad­ing the acoustic sig­nal led to increased alpha pow­er com­pared to non­de­grad­ed stim­uli. The EEG-informed fMRI analy­ses revealed that alpha pow­er cor­re­lat­ed with BOLD changes in infe­ri­or pari­etal cor­tex and right pos­te­ri­or supe­ri­or tem­po­ral gyrus (includ­ing planum tem­po­rale). In both areas, spec­tral degra­da­tion led to a weak­er cou­pling of BOLD response to behav­ioral uti­liza­tion of the spec­tral cue. These data pro­vide con­verg­ing evi­dence from behav­ioral mod­el­ing, elec­tro­phys­i­ol­o­gy, and hemo­dy­nam­ics that (a) increased alpha pow­er medi­ates the inhi­bi­tion of unin­for­ma­tive (here spec­tral) stim­u­lus fea­tures, and that (b) the pari­etal atten­tion net­work sup­ports opti­mal cue uti­liza­tion in audi­to­ry cat­e­go­riza­tion. The results high­light the com­plex cor­ti­cal pro­cess­ing of audi­to­ry cat­e­go­riza­tion under real­is­tic lis­ten­ing chal­lenges.

Ref­er­ences

  • Scharinger M1, Her­rmann B1, Nier­haus T2, Obleser J1. Simul­ta­ne­ous EEG-fMRI brain sig­na­tures of audi­to­ry cue uti­liza­tion. Front Neu­rosci. 2014 Jun 4;8:137. PMID: 24926232. [Open with Read]