Positron emission tomography imaging reveals auditory and frontal cortical regions involved with speech perception and loudness adaptation

Georg Berding, Florian Wilke, Thilo Rode, Cathleen Haense, Gert Joseph, Geerd J. Meyer, Martin Mamach, Minoo Lenarz, Lilli Geworski, Frank M. Bengel, Thomas Lenarz, Hubert H. Lim

Research output: Contribution to journalArticlepeer-review

21 Scopus citations


Considerable progress has been made in the treatment of hearing loss with auditory implants. However, there are still many implanted patients that experience hearing deficiencies, such as limited speech understanding or vanishing perception with continuous stimulation (i.e., abnormal loudness adaptation). The present study aims to identify specific patterns of cerebral cortex activity involved with such deficiencies. We performed O-15-water positron emission tomography (PET) in patients implanted with electrodes within the cochlea, brainstem, or midbrain to investigate the pattern of cortical activation in response to speech or continuous multi-tone stimuli directly inputted into the implant processor that then delivered electrical patterns through those electrodes. Statistical parametric mapping was performed on a single subject basis. Better speech understanding was correlated with a larger extent of bilateral auditory cortex activation. In contrast to speech, the continuous multi-tone stimulus elicited mainly unilateral auditory cortical activity in which greater loudness adaptation corresponded to weaker activation and even deactivation. Interestingly, greater loudness adaptation was correlated with stronger activity within the ventral prefrontal cortex, which could be up-regulated to suppress the irrelevant or aberrant signals into the auditory cortex. The ability to detect these specific cortical patterns and differences across patients and stimuli demonstrates the potential for using PET to diagnose auditory function or dysfunction in implant patients, which in turn could guide the development of appropriate stimulation strategies for improving hearing rehabilitation. Beyond hearing restoration, our study also reveals a potential role of the frontal cortex in suppressing irrelevant or aberrant activity within the auditory cortex, and thus may be relevant for understanding and treating tinnitus.

Original languageEnglish (US)
Article numbere0128743
JournalPloS one
Issue number6
StatePublished - Jun 5 2015

Bibliographical note

Publisher Copyright:
© 2015 Berding et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.


Dive into the research topics of 'Positron emission tomography imaging reveals auditory and frontal cortical regions involved with speech perception and loudness adaptation'. Together they form a unique fingerprint.

Cite this