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Tinnitus research |
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Tinnitus research |
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Poster
abstracts
Pedersen
CB, Ovesen T, Mirz F, Madsen S, Johannsen P, Ishizu K, Gjedde A. Evaluation of time
discrimination in auditory perception. Neuroimage 1997; 5(4): 182. Ishizu K,
Johannsen P, Ovesen T, Mirz F, Gee A, Hansen SB, Pedersen CB, Gjedde A. PET maps of
attention sites to non-semantic auditory stimuli. Neuroimage 1997; 5(4): 190. Ishizu K,
Mirz F, Ovesen T, Johannsen P, Gee A, Hansen SB, Pedersen CB, Gjedde A. Anatomical
symmetry of brain activation: bilateral sites revealed by attention to auditory stimuli.
Neuroimage 1998; 7(4): 83. Ishizu K,
Mirz F, Madsen S, Gee G, Gee A, Hansen SB, Pedersen CB, Gjedde A. Temporal pattern of
brain activation: habituation to auditory stimuli. Neuroimage
1998; 7(4): 366. Mirz F,
Pedersen CB, Ovesen T, Madsen S, Gjedde A. Brain mapping may reveal origins of tinnitus. Neuroimage 1998; 7(4): 386. Mirz F, Gjedde A,
Stødkilde-Jørgensen H, Pedersen CB. Cortical
activation in response to aversive auditory stimuli: a PET study. Neuroimage 1999; 9(6): 802. Mirz F, Gjedde A,
Stødkilde-Jørgensen H, Pedersen CB. Cortical
activation associated with auditory temporal processing. Neuroimage 1999; 9(6): 795. Seto E,
and Mirz F, Stødkilde-Jørgensen H. Effects of sound pressure levels and frequency
content of ambient MR scanner noise on visually stimulated fMRI. Neuroimage 1999; 9(6): 797. Mortensen
MV, Mirz F, Gjedde A. Linking psychophysics and neurophysiology: neuroimaging in Hearing.
Danavox Proceedings. 24. August 2001. Mirz F,
Wetke R, Pedersen CB. A randomized, controlled prospective study of the efficacy of
Tinnitus Retraining Therapy (TRT) - preliminary results. Fifth EFAS Congress. 16. - 20. september 2001,
Bordeaux, Frankrig. Mortensen MV, Mirz F, Pedersen CB, Gjedde A. Auditory cortical responses
in cochlear implant users with different speech perception. Neuroimage 2002.
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| Top | Peer
reviewed articles
Mirz
F, Jørgensen BG, Pedersen CB. Vestibularis-schwannom. Sygdommens incidens og konsekvenser
heraf. Ugeskr
Læger 1998; 160: 6516-6519. Mirz F,
Jørgensen B, Fiirgaard B, Lundorf E, Pedersen CB. Investigations into the natural history
of vestibular schwannoma. Clin Otolaryngol 1999; 24: 13-18. Pedersen CB and Mirz F Ny strategi i
tinnitusbehandlingen. Ugeskr Laeger 1999; 160: 6221-6222. Mirz F,
Zachariae R, Andersen SE, Nielsen AG, Johannsen, LV, Bjerring P, Pedersen CB. The
low-power laser in the treatment of tinnitus. Clin
Otolaryngol 1999; 24: 346-354. Mirz F,
Ovesen T, Ishizu K, Johannsen P, Madsen S, Gjedde A, Pedersen CB. Stimulus-dependent
central processing of auditory stimuli: a PET study.Scand Audiol 1999; 28: 161-169. Pedersen
CB, Mirz F, Ovesen T, Ishizu K, Johannsen P, Madsen, S, Gjedde A. Cortical centers
underlying auditory temporal processing in humans: a PET study. Audiology 2000;39:30-37. Mirz F,
Pedersen CB, Ishizu K, Johannsen P, Ovesen T, Stødkilde-Jørgensen H, Gjedde A. Positron
emission tomography of cortical centers of tinnitus. Hear Res 1999; 134: 133-144. Zachariae
R, Mirz F, Johansen LV, Andersen SE, Bjerring P, Pedersen CB. Reliability and validity of
a Danish adaption of the Tinnitus Handicap Inventory. Scand Audiol 2000; 29: 37-43. Mirz F,
Gjedde A, Stødkilde-Jørgensen H, Pedersen CB. Neuroanatomical correlates of induced
tinnitus. Proceedings of the Sixth International Tinnitus Seminar, Cambridge, England,
323-327, 1999. Mirz F,
Pedersen CB, Fiirgaard B, Lundorf E. Incidence and growth pattern of vestibular
schwannomas in a Danish County 1977-1998. Acta Otolaryngol (Stockh) 2000; Suppl 543: 30-33. Mirz F,
Gjedde A, Ishizu K, Pedersen CB. Cortical networks subserving the perception of tinnitus:
a PET study. Acta Otolaryngol (Stockh) 2000; Suppl 543: 240-243. Thomsen J,
Mirz F, Wetke R, Astrup J, Bojsen-Møller M, Nielsen E. Intracranial sarcoma in a patient
with NF2 treated with gamma-knife radiosurgery for vestibular schwannoma. Am
J Otol 2000, 21: 364-370. Mirz F,
Zachariae R, Andersen SE, Nielsen AG, Johannsen, LV, Bjerring P, Pedersen CB. Behandling af tinnitus med
lav-energi laser. Ugeskr. Laeger 2000, 162: 3607-10. Mirz F, Gjedde A,
Stoedkilde-Joergensen H, Pedersen CB. Functional
brain imaging of tinnitus-like perception induced by aversive auditory stimuli. Neuroreport 2000;11: 633-637. Pedersen
CB, Mirz F. Tinnitus. Ugeskr Prakt. Laegegerning 2002; 80: 463-470. Mirz F,
Mortensen MV, Gjedde A, Pedersen CB. Positron emission tomography of tinnitus suppression
by cochlear implantation. Proceedings of the Seventh International Tinnitus Seminar,
Fremantle, Australia, 136-140, 2002. Mirz F,
Mortensen MV, Madsen S, Gjedde A. Tinnitus suppression by cochlear implantation: a PET
study. Proceedings of the International Conference on Auditory Cortex, Magdeburg, Germany,
79, 2003. Mortensen
MV, Mirz F, Madsen S, Gjdde A. Cortical activity during promontory stimulation in
postlingually deaf adults evaluated by PET. Proceedings of the International Conference on
Auditory Cortex, Magdeburg, Germany, 79-80, 2003. |
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| Top | Books and book chapters
Mirz F,
Pedersen CB. Tinnitusbogen, Munksgaard, Copenhagen 2002. Mirz
F. Øre-, næse-, halssygdomme (Chapter 11) i
Basisbog i sygdomslære. Munksgaard,
Copenhagen 2005.
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PresentationsMirz F et al. Neuroanatomical correlates of induced tinnitus. Sixth International Tinnitus Seminar, Cambridge, UK. (View proceeding) To view
the slide presentations you need Adobe Acrobat Reader. If this program is installed on
your computer just click on the hyperlink to open the slide-file.
Neuroanatomical
correlates of induced tinnitus
Recent
models of tinnitus generation suggest that auditory phantom perception may arise from any
aberrant signal within the auditory system. For all signals, the models claim that
conscious perception takes place in the cerebral cortex. A few functional brain imaging
studies addressed the cerebral mechanisms underlying such perception. To contrast
conditions with and without tinnitus, most studies have concerned rare types of tinnitus
(e.g., tinnitus changeable by oral-facial movement or eye gaze). These studies revealed
variable activation of the auditory cortices and in one study of the hippocampus. In a
recent PET study with intravenous lidocaine or acoustic masking to suppress tinnitus, the
perception of tinnitus implicated activation of a right prefrontal-temporal network.
Besides the evidence of activation of associative auditory sensory regions, these results
also suggested that cortical centers subserving attention and memory may underlie the
continuous annoyance associated with severe tinnitus. The aim of
the present study was to create a neuro-functional model of tinnitus. To imitate the
auditory and emotional experiences associated with tinnitus in patients, we presented
aversive sounds to normal volunteers. Based on our earlier brain imaging studies and
theories of tinnitogenesis, we predicted that the perception of aversive auditory stimuli
activates the auditory cortex, the emotional association centers of the limbic system, and
the prefrontal lobes. Seven
right-handed, healthy volunteers participated in the study. Positron emission tomography
(PET) was used to reveal the expected specific changes in cerebral activity. To induce a
tinnitus-like experience, four sounds were selected from 20 different sounds generated on
the basis of description of sounds perceived by tinnitus patients. To select the four
sounds with the highest impact on the involved neuronal systems, ten subjects not involved
in the PET study rated the aversion, dislike, nuisance, and disturbance caused by the
sounds on a visual-analog-scale (100 mm). Five PET scans were obtained for each subject.
Brain maps from scans with the induced tinnitus experience were contrasted to brain maps
from a baseline condition in a subtraction procedure. Analysis
of the preliminary data revealed activation in the primary auditory cortex bilaterally (BA
41), the superior temporal gyri bilaterally (BA 22), other associative auditory areas in
the left hemisphere (BA 21), prefrontal areas (right superior and middle frontal gyri, and
inferior frontal gyri bilaterally, BA 6, 8, 9, 44, 45), and the limbic system (amygdalae
and parahippocampal gyri bilaterally, BA 28, 34). The results show that processing of aversive auditory stimuli by healthy volunteers elicits activity in neural systems similar to those demonstrated in different PET studies on patients with tinnitus. The consistent activation of primary and associative auditory cortices and limbic system structures confirm that these centers subserve auditory and emotional processing of aversive sounds. The results give indirect evidence for the hypothesis that activation in prefrontal areas may be the underlying neurophysiological substrate of the continuous attention directed towards tinnitus, as suggested in an earlier PET study on tinnitus patients.
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Publications