An integrative assessment of brain and body function 'at rest' in panic disorder: a combined quantitative EEG/autonomic function study.
We conducted a quantitative electroencephalographic (QEEG) and autonomic assessment of panic disorder (PD). The study samples comprised 52 individuals meeting DSM-IV criteria for PD (with or without agoraphobia) and 104 age-, gender-, and handedness-matched controls. EEG data were acquired from 16 scalp sites during resting eyes-open (REO) and eyes-closed (REC) conditions, and spectral power was assessed within 4 frequency bands: theta, alpha-1, alpha-2, and beta. The main findings were an overall reduction of spectral power in PD, compared to controls (Group main effect, p=.011), which was most apparent during REC (Group Condition interaction, p=.014), and within the alpha-1 frequency band (8-11 Hz; Group Band interaction, p=.014). Alpha-1 desynchronization occurs in response to increases in non-specific information processing, and aspects of attention such as alertness. Other findings were region-specific alterations of spectral power at frontal and temporal scalp sites, including a frontal alpha-1 asymmetry (R<L power) during REC in patients, but not controls. Findings for concomitantly-recorded autonomic measures included elevated heart rate, lower heart rate variability, and reduced rate of decrement of skin conductance level in patients, compared to controls. Finally, analyses examining the within-subjects relationship of central and peripheral function measures showed a differential pattern in patients and controls. Possible causes of these disturbances of brain and body function 'at rest', such as patients' ongoing automatic and strategic engagement with multiple disorder-related threat cues, including somatic variability and the testing environment, are discussed.
Wise
Vikki
V
The Centre for Military and Veterans Health, School of Population Health and Clinical Practice, University of Adelaide, Adelaide, Australia. vikki.wise@adelaide.edu.au
McFarlane
Alexander C
AC
Clark
C Richard
CR
Battersby
Malcolm
M
D000328:Adult; D000379:Agoraphobia / Q000209:etiology; D000513:Alpha Rhythm / Q000502:physiology; D001341:Autonomic Nervous System / Q000503:physiopathology*; D001794:Blood Pressure / Q000502:physiology; D016022:Case-Control Studies; D002490:Central Nervous System / Q000503:physiopathology; D004562:Electrocardiography; D004569:Electroencephalography / Q000379:methods; D005260:Female; D005625:Frontal Lobe / Q000503:physiopathology*; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D016584:Panic Disorder / Q000150:complications* / Q000473:pathology*; D011569:Psychiatric Status Rating Scales; D011601:Psychophysics; D012146:Rest