Altered auditory processing in patients with panic disorder: a pilot study.
OBJECTIVE
Clinical and electrophysiological studies suggest that panic disorder (PD) patients show disturbed response inhibition to sensory stimuli. Thus, habituation of neuronal activation after repeated sine tone stimulation was assessed by functional magnetic resonance imaging (fMRI) in patients with PD.


METHODS
Twenty patients with PD and 20 age- and gender-matched healthy controls were assessed by 3T fMRI for auditory habituation. During three stimulation cycles of digitally generated pulsed (ν=5 Hz) 800-Hz sine tones alternating with silent periods, activation of the auditory cortex and other anxiety- or sensory integration-related regions was assessed. Brain activation was further analyzed dependent on functional serotonin transporter (5-HTT) gene variation (5-HTTLPR).


RESULTS
PD patients demonstrated an extended brain activity in the first stimulation block, which normalized during the second stimulation cycle. A positive correlation with anxiety measures (HAMA) and an increased activity of distinct anxiety- or sensory integration-related areas (e.g., BA 22, BA 10) were seen during the third block of auditory stimulation. There was a significant interaction of left amygdala activation and the 5-HTTLPR S allele.


CONCLUSIONS
Our results support the hypothesis of an aberrant processing of sensory information in PD patients. This phenomenon may underlie an enhanced responsiveness to anxiety-relevant or irrelevant stimuli possibly increasing PD vulnerability.
Pfleiderer
Bettina
B
Department of Clinical Radiology, University of Muenster, Muenster, Germany. pfl eide@uni-muenster.de
Zinkirciran
Sariye
S
Michael
Nikolaus
N
Hohoff
Christa
C
Kersting
Anette
A
Arolt
Volker
V
Deckert
Jürgen
J
Domschke
Katharina
K
D000161:Acoustic Stimulation; D000328:Adult; D000483:Alleles; D000679:Amygdala / Q000503:physiopathology; D001007:Anxiety / Q000175:diagnosis / Q000235:genetics / Q000503:physiopathology / Q000523:psychology; D001143:Arousal / Q000502:physiology; D001288:Attention / Q000502:physiology*; D001303:Auditory Cortex / Q000503:physiopathology; D001307:Auditory Perception / Q000502:physiology*; D001921:Brain / Q000503:physiopathology*; D001931:Brain Mapping; D002421:Caudate Nucleus / Q000503:physiopathology; D004292:Dominance, Cerebral / Q000502:physiology; D005260:Female; D005625:Frontal Lobe / Q000503:physiopathology; D005838:Genotype; D006801:Humans; D007089:Image Enhancement; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D009434:Neural Pathways / Q000503:physiopathology; D010100:Oxygen / Q000097:blood; D016584:Panic Disorder / Q000175:diagnosis / Q000235:genetics / Q000503:physiopathology* / Q000523:psychology; D010865:Pilot Projects; D055139:Sensory Gating / Q000502:physiology; D050486:Serotonin Plasma Membrane Transport Proteins / Q000235:genetics
C493230:SLC6A4 protein, human; D050486:Serotonin Plasma Membrane Transport Proteins; D010100:Oxygen