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Auditory Cortex Auditory Neuroscience Auditory Perception EEG / MEG Neural Oscillations Papers Publications Speech

New paper: Her­rmann, Hen­ry, Hae­gens & Obleser in Neuroimage

And again, AC-Alum­ni Björn Her­rmann got a new paper in press / online at Neu­roIm­age on

Tem­po­ral expec­ta­tions and neur­al ampli­tude fluc­tu­a­tions in audi­to­ry cor­tex inter­ac­tive­ly influ­ence perception

Abstract
Align­ment of neur­al oscil­la­tions with tem­po­ral­ly reg­u­lar input allows lis­ten­ers to gen­er­ate tem­po­ral expec­ta­tions. How­ev­er, it remains unclear how behav­ior is gov­erned in the con­text of tem­po­ral vari­abil­i­ty: What role do tem­po­ral expec­ta­tions play, and how do they inter­act with the strength of neur­al oscil­la­to­ry activ­i­ty? Here, human par­tic­i­pants detect­ed near-thresh­old tar­gets in tem­po­ral­ly vari­able acoustic sequences. Tem­po­ral expec­ta­tion strength was esti­mat­ed using an oscil­la­tor mod­el and pre-tar­get neur­al ampli­tudes in audi­to­ry cor­tex were extract­ed from mag­ne­toen­cephalog­ra­phy sig­nals. Tem­po­ral expec­ta­tions mod­u­lat­ed tar­get-detec­tion per­for­mance, how­ev­er, only when neur­al delta-band ampli­tudes were large. Thus, slow neur­al oscil­la­tions act to gate influ­ences of tem­po­ral expec­ta­tion on per­cep­tion. Fur­ther­more, slow ampli­tude fluc­tu­a­tions gov­erned lin­ear and qua­drat­ic influ­ences of audi­to­ry alpha-band activ­i­ty on per­for­mance. By fus­ing a mod­el of tem­po­ral expec­ta­tion with neur­al oscil­la­to­ry dynam­ics, the cur­rent find­ings show that human per­cep­tion in tem­po­ral­ly vari­able con­texts relies on com­plex inter­ac­tions between mul­ti­ple neur­al fre­quen­cy bands.

Cheers.

Ref­er­ences

  • Her­rmann B1, Hen­ry MJ2, Hae­gens S3, Obleser J4. Tem­po­ral expec­ta­tions and neur­al ampli­tude fluc­tu­a­tions in audi­to­ry cor­tex inter­ac­tive­ly influ­ence per­cep­tion. Neu­roim­age. 2015 Sep 18;124(Pt A):487–497. PMID: 26386347. [Open with Read]
Categories
EEG / MEG Neural Oscillations Neural Phase Papers Publications

New Paper out in Psy­chophys­i­ol­o­gy — Wilsch et al.

A new paper on

Slow-delta phase con­cen­tra­tion marks improved tem­po­ral expec­ta­tions based on the pas­sage of time

by AC PhD Anna Wilsch, alum­ni post­docs Mol­ly Hen­ry & Björn Her­rmann, AC head Jonas Obleser along with Burkhard Maess appeared in Psychophysiology.

Check the online source, or take a quick look on the abstract below.

Abstract
Tem­po­ral expec­ta­tions enhance neur­al encod­ing pre­ci­sion, reflect­ed in opti­mized align­ment of slow neur­al oscil­la­to­ry phase, and facil­i­tate sub­se­quent stim­u­lus pro­cess­ing. If an even­t’s exact occur­rence time is unknown, tem­po­ral expec­ta­tions arise sole­ly from the pas­sage of time. Here, we show that this spe­cif­ic type of tem­po­ral expec­ta­tion is also reflect­ed in neur­al phase orga­ni­za­tion. While under­go­ing mag­ne­toen­cephalog­ra­phy, par­tic­i­pants per­formed an audi­to­ry-delayed match­ing-to-sam­ple task with two syl­la­bles (S1, S2). Crit­i­cal­ly, S1-onset time var­ied in the 0.6–1.8‑s (i.e., 0.6−1.7 Hz) range. Increas­ing S1-onset times led to increased slow-delta (0.6−0.9 Hz) phase coher­ence over right fron­totem­po­ral sen­sors dur­ing S1 encod­ing. More­over, indi­vid­u­als with high­er slow-delta coher­ence showed decreased alpha pow­er (8−13 Hz) dur­ing sub­se­quent mem­o­ry reten­tion. In sum, tem­po­ral expec­ta­tions based on the pas­sage of time opti­mize the pre­cise align­ment of neur­al oscil­la­to­ry phase with an expect­ed stimulus.

Ref­er­ences

  • Wilsch A1, Hen­ry MJ, Her­rmann B, Maess B, Obleser J. Slow-delta phase con­cen­tra­tion marks improved tem­po­ral expec­ta­tions based on the pas­sage of time. Psy­chophys­i­ol­o­gy. 2015 Feb 16. PMID: 25684032. [Open with Read]
Categories
Auditory Working Memory Degraded Acoustics EEG / MEG Executive Functions Neural Oscillations Papers Publications Speech

New Paper out: Wilsch, Hen­ry, Her­rmann et al.

Quite recent­ly Cere­bral Cor­tex published

Alpha Oscil­la­to­ry Dynam­ics Index Tem­po­ral Expec­ta­tion Ben­e­fits in Work­ing Memory

by Anna Wilsch, Mol­ly J Hen­ry, Björn Her­rmann, Burkhard Maess, and Jonas Obleser.

Check the abstract below or fol­low that link to get the full arti­cle.

Abstract
Enhanced alpha pow­er com­pared with a base­line can reflect states of increased cog­ni­tive load, for exam­ple, when lis­ten­ing to speech in noise. Can knowl­edge about “when” to lis­ten (tem­po­ral expec­ta­tions) poten­tial­ly coun­ter­act cog­ni­tive load and con­comi­tant­ly reduce alpha? The cur­rent mag­ne­toen­cephalog­ra­phy (MEG) exper­i­ment induced cog­ni­tive load using an audi­to­ry delayed-match­ing-to-sam­ple task with 2 syl­la­bles S1 and S2 pre­sent­ed in speech-shaped noise. Tem­po­ral expec­ta­tion about the occur­rence of S1 was manip­u­lat­ed in 3 dif­fer­ent cue con­di­tions: “Neu­tral” (unin­for­ma­tive about forepe­ri­od), “ear­ly-cued” (short forepe­ri­od), and “late-cued” (long forepe­ri­od). Alpha pow­er through­out the tri­al was high­est when the cue was unin­for­ma­tive about the onset time of S1 (neu­tral) and low­est for the late-cued con­di­tion. This alpha-reduc­ing effect of late com­pared with neu­tral cues was most evi­dent dur­ing mem­o­ry reten­tion in noise and orig­i­nat­ed pri­mar­i­ly in the right insu­la. More­over, indi­vid­ual alpha effects dur­ing reten­tion account­ed best for observed indi­vid­ual per­for­mance dif­fer­ences between late-cued and neu­tral con­di­tions, indi­cat­ing a trade­off between allo­ca­tion of neur­al resources and the ben­e­fits drawn from tem­po­ral cues. Over­all, the results indi­cate that tem­po­ral expec­ta­tions can facil­i­tate the encod­ing of speech in noise, and con­comi­tant­ly reduce neur­al mark­ers of cog­ni­tive load.

Ref­er­ences

  • Wilsch A, Hen­ry MJ, Her­rmann B, Maess B, Obleser J. Alpha Oscil­la­to­ry Dynam­ics Index Tem­po­ral Expec­ta­tion Ben­e­fits in Work­ing Mem­o­ry. Cereb Cor­tex. 2014 Jan 31. PMID: 24488943. [Open with Read]