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Category: Clinical relevance

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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 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
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 Clinical relevance EEG / MEG Evoked Activity Hearing Loss Papers Psychology Publications

New paper in press: Her­rmann et al., Hear­ing Research [Update]

Audi­to­ry fil­ter width affects response mag­ni­tude but not fre­quen­cy speci­fici­ty in audi­to­ry cortex

This is fan­tas­tic news on a fri­day morn­ing: Obleser lab Post­doc Björn Her­rmann teamed up with his fel­low Post­docs Math­ias Scharinger and Mol­ly Hen­ry to study how spec­tral analy­sis in the audi­to­ry periph­ery (termed fre­quen­cy selec­tiv­i­ty) relates to pro­cess­ing in audi­to­ry cor­tex (termed fre­quen­cy speci­fici­ty; see also Björns paper in J Neu­ro­phys­i­ol 2013).

Giv­ing this an age­ing and hear­ing loss per­spec­tive and build­ing on the con­cept of audi­to­ry fil­ters in the cochlea (Moore et al.), Björn found that  the over­all N1 ampli­tude of lis­ten­ers, but not their fre­quen­cy-spe­cif­ic neur­al adap­ta­tion pat­terns, is cor­re­lat­ed with the pass-band of the audi­to­ry filter.

This sug­gests that widened audi­to­ry fil­ters are com­pen­sat­ed for by a response gain in fre­quen­cy-spe­cif­ic areas of audi­to­ry cor­tex; the paper is in press and forth­com­ing in Hear­ing Research.

 

Update:

Paper is avail­able online.

Ref­er­ences

  • Her­rmann B, Hen­ry MJ, Scharinger M, Obleser J. Audi­to­ry fil­ter width affects response mag­ni­tude but not fre­quen­cy speci­fici­ty in audi­to­ry cor­tex. Hear Res. 2013 Oct;304:128–36. PMID: 23876524. [Open with Read]
Categories
Clinical relevance Papers Perception Publications Speech

New paper by Mol­ly Hen­ry: Amu­sia diag­no­sis should bet­ter rely on sig­nal detec­tion theory

Sig­nal detec­tion the­o­ry – what helps pre­vent­ing mis­di­ag­noses and false pos­i­tives in gen­er­al can’t be bad for diag­nos­ing Amu­sia either, one would think. Our very own Mol­ly Hen­ry and her for­mer super­vi­sor Devin McAuley now demon­strate in a just-accept­ed paper

Fail­ure to apply sig­nal detec­tion the­o­ry to the Mon­tre­al Bat­tery of Eval­u­a­tion of Amu­sia may mis­di­ag­nose amusia

in Music Per­cep­tion that this is indeed the case:

They show that analy­ses based on con­fi­dence rat­ings and ROC-curves out­per­forms sim­ple per­cent­age cor­rect in diag­nos­ing Amusia.

Here is the abstract, and watch out for the full paper to appear soon:

This arti­cle con­sid­ers a sig­nal detec­tion the­o­ry (SDT) approach to eval­u­a­tion of per­for­mance on the Mon­tre­al Bat­tery of Eval­u­a­tion of Amu­sia (MBEA).

Con­tin­ue read­ing “New paper by Mol­ly Hen­ry: Amu­sia diag­no­sis should bet­ter rely on sig­nal detec­tion theory”
Categories
Auditory Cortex Auditory Neuroscience Auditory Working Memory Clinical relevance EEG / MEG Neural Oscillations Papers Publications Speech

New paper out: Alpha oscil­la­tions in audition

I am also delight­ed to report the fruits of a very recent col­lab­o­ra­tion with Nathan Weisz and his OBOB lab at the Uni­ver­si­ty of Kon­stanz, Germany.

Alpha Rhythms in Audi­tion: Cog­ni­tive and Clin­i­cal Perspectives

In this review paper, which appears in the new, excit­ing “Fron­tiers in Psy­chol­o­gy” jour­nal, we sum the recent evi­dence that alpha oscil­la­tions (here broad­ly defined from 6 to 13 Hz) are play­ing a very inter­est­ing role in the audi­to­ry sys­tem, just as they do in the visu­al and the somatosen­so­ry system.

In essence, we back Ole Jensen’s and oth­ers’ quite pari­mo­nious idea of alpha as a func­tion­al inhi­bi­tion / gat­ing sys­tem across cor­ti­cal areas.

From our own lab, pre­lim­i­nary data from two recent exper­i­ments is includ­ed: On the role of alpha osil­la­tions as a poten­tial mark­er for speech intel­li­gi­bil­i­ty and its acoustic deter­mi­nants, as well as on speech degra­da­tion and work­ing mem­o­ry load and their com­bined reflec­tion in alpha pow­er increases.

 

NB — the final pdf is still lack­ing, and Front Psy­chol is still not list­ed in PubMed. This should not stop you from sub­mit­ting to their excit­ing new jour­nals, as the review process is very fair and effi­cient and the out­reach via free avail­abil­i­ty promis­es to be considerable.

Ref­er­ences

  • Weisz N, Hart­mann T, Müller N, Lorenz I, Obleser J. Alpha rhythms in audi­tion: cog­ni­tive and clin­i­cal per­spec­tives. Front Psy­chol. 2011 Apr 26;2:73. PMID: 21687444. [Open with Read]
Categories
Auditory Neuroscience Auditory Working Memory Clinical relevance Degraded Acoustics Speech

What is it with degrad­ed speech and work­ing memory?

Upcom­ing mon­day, I will present in-house some of my recent rumi­nat­ing on the con­cept of “ver­bal” work­ing mem­o­ry and on-line speech com­pre­hen­sion. It is an ancient issue that received some atten­tion main­ly in the 1980s, in the light of Baddeley’s great (read: testable) work­ing mem­o­ry archi­tec­ture includ­ing the now famous phono­log­i­cal store or buffer.

Now, when we turn to degrad­ed speech (or, degrad­ed hear­ing, for that mat­ter) and want to under­stand how the brain can extract mean­ing from a degrad­ed sig­nal, the debate as to whether or not this requires work­ing mem­o­ry has to be revived.

My main con­cern is that the con­cept of a phono­log­i­cal store always relies on

“rep­re­sen­ta­tions […] which […] must, rather, be post-cat­e­gor­i­cal, ‘cen­tral’ rep­re­sen­ta­tions that are func­tion­al­ly remote from more periph­er­al per­cep­tu­al or motoric sys­tems.

Indeed, the use of the term phono­log­i­cal seems to have been delib­er­ate­ly adopt­ed in favor of the terms acoustic or artic­u­la­to­ry (see, e.g., Bad­de­ley, 1992) to indi­cate the abstract nature of the phono­log­i­cal store’s unit of currency.’’

(Jones, Hugh­es, & Mack­en, 2006, p. 266; quot­ed after the worth­while paper by Pa et al.)

But how does the hear­ing sys­tem arrive at such an abstract rep­re­sen­ta­tion when the input is com­pro­mised and less than clear?

I think it all leads to an—at least—twofold under­stand­ing of “work­ing” mem­o­ry in acoustic and speech process­es, each with its own neur­al cor­re­lates, as they sur­face in any brain imag­ing study of lis­ten­ing to (degrad­ed) speech: A pre-cat­e­gor­i­cal, sen­so­ry-based sys­tem, prob­a­bly reflect­ed by acti­va­tions of the planum tem­po­rale that can be tied to com­pen­sato­ry and effort­ful attempts to process the speech signal—and a (more clas­si­cal) post-cat­e­gor­i­cal sys­tem not access­ing acoustic detail any longer and con­nect­ing to long-term mem­o­ry rep­re­sen­ta­tions (phono­log­i­cal and lex­i­cal cat­e­gories) instead.

Stay tuned for more of this.

Categories
Auditory Neuroscience Clinical relevance Editorial Notes Speech

Why will a per­son with a right-hemi­spher­ic stroke not become aphasic…

… if spec­tral (fine-fre­quen­cy) details of the speech sig­nal are “pre­dom­i­nant­ly tracked in the right audi­to­ry cor­tex”, Prof. Sophie Scott just right­ly asked after my talk fif­teen min­utes ago at SfN.

I am not sure what Robert Zatorre and David Poep­pel would answer, but I think that this is not an easy ques­tion and it can sure­ly not be answered based on the first exper­i­ment on spec­tral vs. tem­po­ral detail in speech that we just published. 

I would argue that it is open to thor­ough test­ing how patients with left or right tem­po­ral lobe lesions would cope with removed spec­tral and tem­po­ral detail, respectively.

I am glad that Sophie Scott some­what sug­gest­ed this, as I have been main­tain­ing for years the opin­ion that in lesioned patients, apha­sic or not, there is much to learn on fine-grad­ed, basic audi­to­ry processing—it is high­ly under­stand­able that, from a clin­i­cal point of view, patients have much more severe prob­lems in com­mu­ni­ca­tion that deserve our clin­i­cal atten­tion. Nev­er­the­less, thor­ough (behav­iour­al) test­ing of the audi­to­ry speech per­cep­tion in vol­un­teer­ing patients is a worth­while and time­ly effort.