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Tag: acoustic cues

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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]
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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]
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]