From: Exp Brain Res. 2010 Feb 26. [Epub ahead of print]
Tinnitus is considered as an auditory phantom percept. Preliminary evidence indicates that transcranial direct current stimulation of the temporo-parietal area might reduce tinnitus. Transcranial direct current stimulation studies of the prefrontal cortex have been successful in reducing depression, impulsiveness and pain. Recently, it was shown that the prefrontal cortex is important for the integration of sensory and emotional aspects of tinnitus. As such, frontal transcranial direct current stimulation might suppress tinnitus as well. In an open label study, a total of 478 tinnitus patients received bilateral transcranial direct current stimulation on dorsolateral prefrontal cortex (448 patients anode right, cathode left and 30 anode left, cathode right) for 20 min. Treatment effects were assessed with visual analogue scale for tinnitus intensity and distress.
No tinnitus suppressing effect was found for transcranial direct current stimulation with left anode and right cathode. Analyses show that transcranial direct current stimulation with right anode and left cathode modulates tinnitus perception in 29.9% of the tinnitus patients. For these responders a significant reduction was found for both tinnitus related distress and tinnitus intensity. In addition, the amount of suppression for tinnitus related distress is moderated by an interaction between tinnitus type and tinnitus laterality. This was, however, not the case for tinnitus intensity. This study supports the involvement of the prefrontal cortex in the pathophysiology of tinnitus.
Related: Chronic Back Pain Is Associated with Decreased Prefrontal and Thalamic Gray Matter Density There was a relationship between the dorsolateral prefrontal cortex and perceived pain. The authors suggested that the pattern of brain atrophy is directly related to the perceptual and behavioral properties of chronic back pain. Gray matter density was reduced in bilateral dorsolateral prefrontal cortex and right thalamus and was strongly related to pain characteristics in a pattern distinct for neuropathic and non-neuropathic chronic back pain.
Is there a relationship between chronic pain and tinnitus?
According to Psychophysiology. 2010 Jan 11. [Epub ahead of print] Localization of asymmetric brain function in emotion and depression. “These data confirm that emotional stimulus processing and trait depression are associated with asymmetric brain functions in distinct subregions of the DLPFC [dorsolateral prefrontal cortex] that may go undetected unless appropriate analytic procedures are used.”
Additionally, in Biol Psychiatry. 2008 Feb 15;63(4):369-76. Epub 2007 Sep 21. Imbalance between left and right dorsolateral prefrontal cortex in major depression is linked to negative emotional judgment: an fMRI study in severe major depressive disorder. “Results demonstrate that left DLPFC hypoactivity is associated with negative emotional judgment rather than with emotional perception or attention while right DLPFC hyperactivity is linked to attentional modulation. Left-right DLPFC imbalance is characterized in neuropsychological regard, which bridges the gap from resting metabolism and therapeutic repetitive transcranial magnetic stimulation effects to functional neuroanatomy of altered emotional-cognitive interaction in MDD [major depressive disorder].”
Comment by Administrator — February 27, 2010 @ 7:21 am