Iris Sommer, May 22
Where the voices come from; and how to get rid of them
Psychiatry Department, University Medical Centre Utrecht
Auditory verbal hallucinations (AVH), or hearing voices, is a frequent and characteristic symptom of schizophrenia. In most patients, these hallucinations disappear with antipsychotic medication, but some 25% of patients have medication-resistant hallucinations. Intractable hallucinations are a stressful symptom that significantly reduces the quality of life and are associated with the risk for suicide and aggression against others. At the Voices Clinic Utrecht, we seek to understand the pathophysiology of hallucinations and create new treatments for medication-resistant patients.
Using BOLD fMRI to investigate the state-related activity associated with AVH, we found the left and right temporo-parietal regions are active, but also inferior frontal regions. When activation during AVH was compared to inner speech, AVH were associated with more activation of right-sided areas especially in the inferior frontal region. We also investigated BOLD signal changes immediately prior to the AVH and found involvement of the parahippocampal region. Our theory is that this reflects spontaneous recollection from memory to trigger AVH. We applied two imaging techniques to assess the quality of the fibers in patients with AVH and found an indication that the arcuate fasciculus may contain more free water, leading to a lower quality of this connection.
Finally, we tried to create a new treatment module by applying fMRI-guided TMS, a technique that can focally reduce brain activity. So far, both 1Hz stimulation and priming TMS were not significantly superior to sham. We now investigate if theta-burst TMS may be more effective.
- Where and when:
15:45-17:00 May 22, 2012MPI Nijmegen, Rm 163