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Category: Psychology

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
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
Auditory Neuroscience Auditory Speech Processing EEG / MEG Linguistics Papers Psychology Publications Speech

New paper out: Are ear­ly N100 and the late Gam­ma-band response neg­a­tive­ly cor­re­lat­ed in com­pre­hen­sion of degrad­ed speech?

Late 2010 was par­tic­u­lar­ly good to us:

Mul­ti­ple brain sig­na­tures of inte­gra­tion in the com­pre­hen­sion of degrad­ed speech

by Jonas Obleser and Son­ja Kotz, in Neu­roIm­age.

The final pdf will hope­ful­ly be avail­able online very soon. Mean­while the fig­ure below cap­tures our main results:

Ref­er­ences

  • Obleser J, Kotz SA. Mul­ti­ple brain sig­na­tures of inte­gra­tion in the com­pre­hen­sion of degrad­ed speech. Neu­roim­age. 2011 Mar 15;55(2):713–23. PMID: 21172443. [Open with Read]