Alpha rhythm and hypofrontality in schizophrenia.
OBJECTIVE
To reveal the EEG correlates of resting hypofrontality in schizophrenia (SZ).


METHODS
We analyzed the whole-head EEG topography in 14 patients compared to 14 matched controls by applying a new parameterization of the multichannel EEG. We used a combination of power measures tuned for regional surface mapping with power measures that allow evaluation of global effects.


RESULTS
The SZ-related EEG abnormalities include i) a global decrease in absolute EEG power robustly manifested in the alpha and beta frequency bands, and ii) a relative increase in the alpha power over the prefrontal brain regions against its reduction over the posterior regions. In the alpha band both effects are linked to the SZ symptoms measured with Positive and Negative Symptom Scales and to chronicity.


CONCLUSIONS
As alpha activity is related to regional deactivation, our findings support the concept of hypofrontality in SZ and expose the alpha rhythm as a sensitive indicator of it.
Knyazeva
M G
MG
Department of Neurology, Centre Hospitalier Universitaire Vaudois and University of Lausanne and Department of Radiology, Centre Hospitalier Universitaire Vaudois and University of Lausanne, Lausanne, Switzerland. maria.knyazeva@chuv.ch
Jalili
M
M
Meuli
R
R
Hasler
M
M
De Feo
O
O
Do
K Q
KQ
D000293:Adolescent; D000328:Adult; D000513:Alpha Rhythm / Q000379:methods* / Q000706:statistics & numerical data*; D001931:Brain Mapping / Q000379:methods; D004292:Dominance, Cerebral; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017397:Prefrontal Cortex / Q000503:physiopathology*; D011569:Psychiatric Status Rating Scales; D015203:Reproducibility of Results; D012146:Rest; D012559:Schizophrenia / Q000175:diagnosis / Q000188:drug therapy / Q000503:physiopathology*; D012565:Schizophrenic Psychology; D012680:Sensitivity and Specificity; D012815:Signal Processing, Computer-Assisted; D055815:Young Adult