TY - JOUR
T1 - Neuromagnetic indicators of tinnitus and tinnitus masking in patients with and without hearing loss
AU - Adjamian, Peyman
AU - Sereda, Magdalena
AU - Zobay, Oliver
AU - Hall, Deborah A.
AU - Palmer, Alan R.
N1 - Funding Information:
We would like to thank Dr. Trevor Shackleton for his assistance with stimulus delivery equipment and Dr. Matthew Brookes for his suggestions regarding data collection methods. We would like to thank Dr. Thomasina Meehan, Consultant Audiovestibular Physician at the Nottingham University Hospitals Trust, for her assistance in recruitment of TI participants. Deb Hall is supported by the National Institute for Health Research (NIHR).
PY - 2012/10
Y1 - 2012/10
N2 - Tinnitus is an auditory phenomenon characterised by the perception of a sound in the absence of an external auditory stimulus. Chronic subjective tinnitus is almost certainly maintained via central mechanisms, and this is consistent with observed measures of altered spontaneous brain activity. A number of putative central auditory mechanisms for tinnitus have been proposed. The influential thalamocortical dysrhythmia model suggests that tinnitus can be attributed to the disruption of coherent oscillatory activity between thalamus and cortex following hearing loss. However, the extent to which this disruption specifically contributes to tinnitus or is simply a consequence of the hearing loss is unclear because the necessary matched controls have not been tested. Here, we rigorously test several predictions made by this model in four groups of participants (tinnitus with hearing loss, tinnitus with clinically normal hearing, no tinnitus with hearing loss and no tinnitus with clinically normal hearing). Magnetoencephalography was used to measure oscillatory brain activity within different frequency bands in a 'resting' state and during presentation of a masking noise. Results revealed that low-frequency activity in the delta band (1-4 Hz) was significantly higher in the 'tinnitus with hearing loss' group compared to the 'no tinnitus with normal hearing' group. A planned comparison indicated that this effect was unlikely to be driven by the hearing loss alone, but could possibly be a consequence of tinnitus and hearing loss. A further interpretative linkage to tinnitus was given by the result that the delta activity tended to reduce when tinnitus was masked. High-frequency activity in the gamma band (25-80 Hz) was not correlated with tinnitus (or hearing loss). The findings partly support the thalamocortical dysrhythmia model and suggest that slow-wave (delta band) activity may be a more reliable correlate of tinnitus than high-frequency activity.
AB - Tinnitus is an auditory phenomenon characterised by the perception of a sound in the absence of an external auditory stimulus. Chronic subjective tinnitus is almost certainly maintained via central mechanisms, and this is consistent with observed measures of altered spontaneous brain activity. A number of putative central auditory mechanisms for tinnitus have been proposed. The influential thalamocortical dysrhythmia model suggests that tinnitus can be attributed to the disruption of coherent oscillatory activity between thalamus and cortex following hearing loss. However, the extent to which this disruption specifically contributes to tinnitus or is simply a consequence of the hearing loss is unclear because the necessary matched controls have not been tested. Here, we rigorously test several predictions made by this model in four groups of participants (tinnitus with hearing loss, tinnitus with clinically normal hearing, no tinnitus with hearing loss and no tinnitus with clinically normal hearing). Magnetoencephalography was used to measure oscillatory brain activity within different frequency bands in a 'resting' state and during presentation of a masking noise. Results revealed that low-frequency activity in the delta band (1-4 Hz) was significantly higher in the 'tinnitus with hearing loss' group compared to the 'no tinnitus with normal hearing' group. A planned comparison indicated that this effect was unlikely to be driven by the hearing loss alone, but could possibly be a consequence of tinnitus and hearing loss. A further interpretative linkage to tinnitus was given by the result that the delta activity tended to reduce when tinnitus was masked. High-frequency activity in the gamma band (25-80 Hz) was not correlated with tinnitus (or hearing loss). The findings partly support the thalamocortical dysrhythmia model and suggest that slow-wave (delta band) activity may be a more reliable correlate of tinnitus than high-frequency activity.
KW - Cortical oscillations
KW - Magnetoencephalography
KW - Thalamocortical dysrhythmia
KW - Tinnitus masking
UR - http://www.scopus.com/inward/record.url?scp=84870415461&partnerID=8YFLogxK
U2 - 10.1007/s10162-012-0340-5
DO - 10.1007/s10162-012-0340-5
M3 - Article
C2 - 22791191
AN - SCOPUS:84870415461
SN - 1525-3961
VL - 13
SP - 715
EP - 731
JO - JARO - Journal of the Association for Research in Otolaryngology
JF - JARO - Journal of the Association for Research in Otolaryngology
IS - 5
ER -