Categories
Ageing Auditory Cortex Events Perception Psychology

Sym­po­sium at PuG 2018

Dur­ing the upcom­ing meet­ing of “Psy­chol­o­gy and the Brain 2018”, PhD stu­dent Leo Waschke will be host­ing a sym­po­sium on states and traits of neur­al activ­i­ty and their func­tion­al rel­e­vance for per­cep­tion and age­ing. Togeth­er with Lin­da Geerligs (Don­ders Insti­tute, NL), Marieke Schölvinck (ESI, Frank­furt) and Niels Kloost­er­man (MPIB, Berlin) he will be address­ing fluc­tu­a­tions in brain activ­i­ty on a host of timescales from mil­lisec­onds to min­utes. We are look­ing for­ward to meet­ing you in Giessen.

Categories
Auditory Perception Clinical relevance Papers Perception Psychology Publications

New paper out in the ‘Euro­pean Jour­nal of Neu­ro­science’: Tune, Wöst­mann & Obleser

AC post­docs Sarah Tune and Malte Wöst­mann have a new paper out online in the spe­cial issue on Neur­al Oscil­la­tions in the Euro­pean Jour­nal of Neu­ro­science! We are excit­ed to share the results from our first study of the ERC-fund­ed project on lis­ten­ing behav­ior and adap­tive con­trol in mid­dle-aged adults. In this study, we asked whether the fideli­ty of alpha pow­er lat­er­al­iza­tion would serve as a neur­al mark­er of selec­tive audi­to­ry atten­tion in the age­ing lis­ten­er. The results of our mul­ti­vari­ate approach demon­strate that under­stand­ing inter-indi­vid­ual dif­fer­ences is para­mount to under­stand­ing of the role of alpha oscil­la­tions in audi­to­ry atten­tion across age.

Tune, S., Wöst­mann, W., & Obleser, J. (2018) Prob­ing the lim­its of alpha pow­er lat­er­al­i­sa­tion as a neur­al mark­er of selec­tive atten­tion in mid­dle-aged and old­er listeners.

Now avail­able online:

http://onlinelibrary.wiley.com/doi/10.1111/ejn.13862/full/

 

Categories
Adaptive Control Attention Auditory Working Memory Clinical relevance Executive Functions fMRI Papers Psychology Publications Uncategorized

New paper in press in ‘Neu­roim­age’: Alavash, Lim, et al

Oble­ser­lab post­doc Mohsen Alavash and Oble­ser­lab Alum­na Sung-Joo Lim are in press at Neu­roim­age!

They argue with data from a place­bo-con­trolled dopamin­er­gic inter­ven­tion study that BOLD sig­nal vari­abil­i­ty and the func­tion­al con­nec­tome are sur­pris­ing­ly clear­ly affect­ed by L‑Dopa, and (ii) that the degree of change in these met­rics can explain the degree to which indi­vid­u­als will prof­it from L‑DOPA in per­form­ing the chal­leng­ing lis­ten­ing task (while oth­ers dont; Preprint here ).

Alavash, M., Lim, S.J., Thiel, C., Sehm, B., Deser­no, L., & Obleser, J. (2018) Dopamin­er­gic mod­u­la­tion of hemo­dy­nam­ic sig­nal vari­abil­i­ty and the func­tion­al con­nec­tome dur­ing cog­ni­tive per­for­mance. Neu­roim­age. In press.

— Thanks also and in par­tic­u­lar to our col­leagues Chris­tiane Thiel of Old­en­burg, and Bern­hard Sehm and Lorenz Deser­no of Leipzig, who helped us made this large-scale L‑DOPA project happen!

 

 

Categories
Auditory Cortex Auditory Neuroscience Brain stimulation Clinical relevance Degraded Acoustics Hearing Loss Neural Oscillations Neural Phase Papers Psychology Speech

New paper in press with the Old­en­burg brain-stim­u­la­tion crew!

AC alum­na Anna Wilsch has a new paper in press in Neu­roim­age, with Toralf Neul­ing, Jonas Obleser, and Christoph Her­rmann: “Tran­scra­nial alter­nat­ing cur­rent stim­u­la­tion with speech envelopes mod­u­lates speech com­pre­hen­sion”. In this proof-of-concept–like paper, we demon­strate that using the speech enve­lope as a “pilot sig­nal” for elec­tri­cal­ly stim­u­lat­ing the human brain, while a lis­ten­er tries to com­pre­hend that speech sig­nal buried in noise, does mod­u­late the listener’s speech–in–noise com­pre­hen­sion abilities.

The Preprint is here, … 

… while the abstract goes like this:
Cor­ti­cal entrain­ment of the audi­to­ry cor­tex to the broad­band tem­po­ral enve­lope of a speech sig­nal is cru­cial for speech com­pre­hen­sion. Entrain­ment results in phas­es of high and low neur­al excitabil­i­ty, which struc­ture and decode the incom­ing speech sig­nal. Entrain­ment to speech is strongest in the theta fre­quen­cy range (4−8 Hz), the aver­age fre­quen­cy of the speech enve­lope. If a speech sig­nal is degrad­ed, entrain­ment to the speech enve­lope is weak­er and speech intel­li­gi­bil­i­ty declines. Besides per­cep­tu­al­ly evoked cor­ti­cal entrain­ment, tran­scra­nial alter­nat­ing cur­rent stim­u­la­tion (tACS) entrains neur­al oscil­la­tions by apply­ing an elec­tric sig­nal to the brain. Accord­ing­ly, tACS-induced entrain­ment in audi­to­ry cor­tex has been shown to improve audi­to­ry per­cep­tion. The aim of the cur­rent study was to mod­u­late speech intel­li­gi­bil­i­ty exter­nal­ly by means of tACS such that the elec­tric cur­rent cor­re­sponds to the enve­lope of the pre­sent­ed speech stream (i.e., enve­lope-tACS). Par­tic­i­pants per­formed the Old­en­burg sen­tence test with sen­tences pre­sent­ed in noise in com­bi­na­tion with enve­lope-tACS. Crit­i­cal­ly, tACS was induced at time lags of 0 to 250 ms in 50-ms steps rel­a­tive to sen­tence onset (audi­to­ry stim­uli were simul­ta­ne­ous to or pre­ced­ed tACS). We per­formed sin­gle- sub­ject sinu­soidal, lin­ear, and qua­drat­ic fits to the sen­tence com­pre­hen­sion per­for­mance across the time lags. We could show that the sinu­soidal fit described the mod­u­la­tion of sen­tence com­pre­hen­sion best. Impor­tant­ly, the aver­age fre­quen­cy of the sinu­soidal fit was 5.12 Hz, cor­re­spond­ing to the peaks of the ampli­tude spec­trum of the stim­u­lat­ed envelopes. This find­ing was sup­port­ed by a sig­nif­i­cant 5‑Hz peak in the aver­age pow­er spec­trum of indi­vid­ual per­for­mance time series. Alto­geth­er, enve­lope tACS mod­u­lates intel­li­gi­bil­i­ty of speech in noise, pre­sum­ably by enhanc­ing and dis­rupt­ing (time lag with in- or out-of-phase stim­u­la­tion, respec­tive­ly) cor­ti­cal entrain­ment to the speech enve­lope in audi­to­ry cortex.
Categories
Auditory Neuroscience Auditory Speech Processing Psychology

SNAP 2017 was a vast success

SNAP 2017 took place on Decem­ber 8 and 9 in Lübeck, Germany.

Nine inter­na­tion­al­ly esteemed speak­ers and in total more than six­ty researchers from all over Europe, Cana­da and the US made the sec­ond Sig­nal and Noise Along the Audi­to­ry Path­way work­shop a mem­o­rable occa­sion in audi­to­ry neuroscience.

Thanks to every­body for com­ing out!, and see you all again for SNAP 2019, at a loca­tion to be announced.

Categories
Ageing Auditory Neuroscience EEG / MEG Papers Publications

New paper online by Waschke, Wöst­mann & Obleser

Read all about neur­al irreg­u­lar­i­ty in aging brains and how it relates to per­cep­tu­al deci­sions: New paper by PhD stu­dent Leo Waschke. 

Now avail­able online:
https://goo.gl/F4dFfe

Abstract

Sen­so­ry rep­re­sen­ta­tions, and thus human per­cepts, of the phys­i­cal world are sus­cep­ti­ble to fluc­tu­a­tions in brain state or “neur­al irreg­u­lar­i­ty”. Fur­ther­more, aging brains dis­play altered lev­els of neur­al irreg­u­lar­i­ty. We here show that a sin­gle, with­in-tri­al, infor­ma­tion-the­o­ret­ic mea­sure (weight­ed per­mu­ta­tion entropy) cap­tures neur­al irreg­u­lar­i­ty in the human elec­troen­cephalo­gram as a proxy for both, trait-like dif­fer­ences between indi­vid­u­als of vary­ing age, and state-like fluc­tu­a­tions that bias per­cep­tu­al deci­sions. First, the over­all lev­el of neur­al irreg­u­lar­i­ty increased with par­tic­i­pants’ age, par­al­leled by a decrease in vari­abil­i­ty over time, like­ly index­ing age-relat­ed changes at struc­tur­al and func­tion­al lev­els of brain activ­i­ty. Sec­ond, states of high­er neur­al irreg­u­lar­i­ty were asso­ci­at­ed with opti­mized sen­so­ry encod­ing and a sub­se­quent­ly increased prob­a­bil­i­ty of choos­ing the first of two phys­i­cal­ly iden­ti­cal stim­uli to be high­er in pitch. In sum, neur­al irreg­u­lar­i­ty not only char­ac­ter­izes behav­ioural­ly rel­e­vant brain states, but also can iden­ti­fy trait-like changes that come with age. 

 

 

Categories
Adaptive Control Ageing Job Offers Speech Uncategorized

Want to come work with us?

Post­doc posi­tion in the Obleser lab, in the ERC-fund­ed project “Audadapt” — dead­line for appli­ca­tions very soon! (Nov 30 2017). Check out all appli­ca­tions details here!

Categories
Uncategorized

SNAP 2017 — Timetable now online!

SNAP 2017 is draw­ing clos­er. Get ready and take a look at the program:

Day 1: 08.12.2017
Time
08:00 — 09:10 Reg­is­tra­tion / Open­ing remarks
(9:00–9:10)
09:10 — 10:00 Edmund Lalor
10:00 — 10:50 Sarah Ver­hulst
10:50 — 11:10 Cof­fee break
11:10 — 12:00 Christoph Kayser
12:00 — 12:30 Dis­cus­sion (Impuls­es by Son­ja Kotz)
12:30 — 14:00 Lunch
14:00 — 14:50 Tom Fran­cart
14:50 — 15:40 Nima Mes­garani
15:40 — 16:00 Cof­fee break
16:00 — 18:00 Posters and beers
19:00 Speak­ers Din­ner at Bud­dha Bowl
21:00 SNAP Par­ty at Gang 56
Day 2: 09.12.2017
Time
09:30 — 10:20 Jen­nifer Bizley
10:20 — 11:10 Sami­ra Anderson
11:10 — 11:30 Cof­fee break
11:30 — 12:20 Maria Chait
12:20 — 12:50 Dis­cus­sion (Impuls­es by Thomas Münte)
13:00 — 14:00 Lunch
14:00 — 14:50 Josh McDer­mott
14:50 — 15:30 Round-table / Wrap-up