Arthur Peter Wunderlich PhD, Abstract Co-Author: Nothing to Disclose

Carlos Schönfeldt-Lecuona MD, Abstract Co-Author: Nothing to Disclose

Ulrich Hoffmann, Abstract Co-Author: Nothing to Disclose

Wolfgang Freund MD, Presenter: Nothing to Disclose

To study neural correlates of tinnitus by comparing fMRI activation patterns of a language task presented together with auditory stimuli in tinnitus patients and age-matched healthy volunteers.

Six tinnitus patients and six healthy, normally hearing volunteers were scanned with fMRI. A word-pair-paradigm was presented with MR-compatible video goggles using a block duration of 28 sec. Simultaneously, different tones were presented as beeps at a rate of 5 per second in blocks of 32 sec pseudorandomized together with silence blocks of the same length. A sufficient number of blocks was presented to evaluate cortical responses to both stimuli. Subjects’ attention was directed to the visual stimuli with the advice to perform the word pair task and to ignore the beeps. On a Siemens Magnetom Vision MR scanner (1.5 T), we got 37 slices covering the whole brain. Data analysis was performed with SPM 99. The language task as well as effects of the acoustic stimulation were evaluated. A group analysis was performed to visualize main effects of both groups as well as differences between groups (p < 0.001).

In the word-pair-paradigm, the patient group shows bilateral activation of primary and secondary acoustic areas, whereas the control group shows only visual association fields and left premotor areas adjacent to the area of Broca. Analyzing effects of the beeps, both groups show similar activation of auditory areas, with markedly higher z-values for secondary auditory areas in patients. The significance of this difference is confirmed by the contrast patients-controls.

The presented two-stimuli-paradigm results in marked cortical activation in tinnitus patients and controls. Patients exhibit strong cortical activation of auditory areas under the instruction to concentrate on a optically presented speech task. This may be interpreted as the failure to dissociate from the auditory stimuli or a cross-activation of auditory areas and is not shown in the group of healthy controls.

Tinnitus is widely regarded as a malfunction of auditory perception, so we studied neuronal correlates of acoustic distraction in tinnitus patients and controls to improve therapeutic strategies.

Wunderlich, A, Schönfeldt-Lecuona, C, Hoffmann, U, Freund, W, Cortical Activity of Tinnitus Patients and Controls in a Distraction Study.  Radiological Society of North America 2006 Scientific Assembly and Annual Meeting, November 26 - December 1, 2006 ,Chicago IL. http://archive.rsna.org/2006/4433595.html