RT Journal Article
SR Electronic
T1 The Brain Dynamics of Rapid Perceptual Adaptation to Adverse Listening Conditions
JF The Journal of Neuroscience
JO J. Neurosci.
FD Society for Neuroscience
SP 10688
OP 10697
DO 10.1523/JNEUROSCI.4596-12.2013
VO 33
IS 26
A1 Julia Erb
A1 Molly J. Henry
A1 Frank Eisner
A1 Jonas Obleser
YR 2013
UL http://www.jneurosci.org/content/33/26/10688.abstract
AB Listeners show a remarkable ability to quickly adjust to degraded speech input. Here, we aimed to identify the neural mechanisms of such short-term perceptual adaptation. In a sparse-sampling, cardiac-gated functional magnetic resonance imaging (fMRI) acquisition, human listeners heard and repeated back 4-band-vocoded sentences (in which the temporal envelope of the acoustic signal is preserved, while spectral information is highly degraded). Clear-speech trials were included as baseline. An additional fMRI experiment on amplitude modulation rate discrimination quantified the convergence of neural mechanisms that subserve coping with challenging listening conditions for speech and non-speech. First, the degraded speech task revealed an “executive” network (comprising the anterior insula and anterior cingulate cortex), parts of which were also activated in the non-speech discrimination task. Second, trial-by-trial fluctuations in successful comprehension of degraded speech drove hemodynamic signal change in classic “language” areas (bilateral temporal cortices). Third, as listeners perceptually adapted to degraded speech, downregulation in a cortico-striato-thalamo-cortical circuit was observable. The present data highlight differential upregulation and downregulation in auditory–language and executive networks, respectively, with important subcortical contributions when successfully adapting to a challenging listening situation.