Hemisphere Asymmetry of Alpha Burst Frequency of Occurrence Variations in Depression

et al. 2020

BMC Psychiatry

Background Electroencephalography (EEG) frontal alpha asymmetry (FAA) has been observed in several psychiatric disorders. Dominance in left or right frontal alpha activity remains inconsistent in patients with major depressive disorder (MDD), patients with schizophrenia, and healthy controls. This study compared FAA among patients with MDD and schizophrenia, and healthy controls. Methods We recruited 20 patients with MDD, 18 patients with schizophrenia, and 16 healthy individuals. The EEG alpha frequency ranged from 8 Hz to 12 Hz. FAA was expressed as the difference between absolute power values of right and left hemisphere electrodes in the alpha frequency range (common-log-transformed frontal right- and left-hemisphere electrodes: F4–F3, F8–F7, FP2–FP1, AF4–AF3, F6–F5, and F2–F1). Hamilton depression and anxiety rating scales were evaluated in patients with MDD. Positive and negative syndrome scales were evaluated in patients with schizophrenia. Results Patients with schizophrenia showed significantly lower left FAA than healthy controls (F4–F3, schizophrenia vs. healthy controls: − 0.10 ± 0.04 vs. -0.05 ± 0.05). There were no significant differences in FAA between patients with schizophrenia and MDD as well as between patients with MDD and healthy controls. Conclusions The present study suggests that FAA indicates a relatively lower activation of left frontal electrodes in schizophrenia. The left-lateralized FAA could be a neuropathological attribute in patients with schizophrenia, but a lack of sample size and information such as medication and duration of illness might obscure the interpretation and generalization of our findings. Thus, further studies to verify the findings would be warranted.

Section: Participantsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Comparison of frontal alpha asymmetry among schizophrenia patients, major depressive disorder patients, and healthy controls

Jang

et al. 2020

BMC Psychiatry

“…Although electroencephalographic frontal alpha asymmetry (FAA) has been suggested to be a clinical biomarker for the abnormal behavioral phenotype of major depressive disorder (MDD) [1][2][3][4][5][6][7][8][9], con icting results in prior research have contested this view [10,11]. A previous meta-analysis of 1,883 individuals with MDD and 2,161 controls found that FAA's diagnostic value was not signi cant [11].…”

Section: Introductionmentioning

confidence: 99%

Comparison of Frontal Alpha Asymmetry Among Schizophrenia Patients, Major Depressive Disorder, and Healthy Controls

Jang¹,

et al. 2020

Preprint

Background Electroencephalography (EEG) frontal alpha asymmetry (FAA) has been observed in several psychiatric disorders. However, dominance in left or right frontal alpha activity remains inconsistent in patients with major depressive disorder (MDD), patients with schizophrenia, and healthy controls. This study compared FAA among patients with MDD, schizophrenia, and healthy control. Methods We recruited 20 patients with MDD, 18 patients with schizophrenia, and 16 healthy individuals. The EEG alpha frequency ranged from 8.0 to 12.0 Hz. FAA was expressed as the difference between absolute power values in both the right and left electrodes in the alpha frequency range (common-log-transformed F4–F3 and F8–F7). Hamilton depression and anxiety rating scales were evaluated in patients with MDD. Positive and negative syndrome scales were evaluated in patients with schizophrenia. Results Patients with schizophrenia showed significantly lower left frontal lobe activity than healthy controls (FAA, schizophrenia vs. healthy: -0.10 ± 0.05 vs. -0.05 ± 0.05). There were no significant differences in FAA between patients with schizophrenia and MDD as well as between patients with MDD and healthy controls. Conclusions The present study suggests that frontal alpha asymmetry indicates a breaking neural activity in schizophrenia. Breaking rhythmic activity as a left-lateralized FAA can be a neuropathological attribute in patients with schizophrenia but lack of sample size and information such as medication and duration of illness, all of which could make it difficult generalize finding.

“…Although electroencephalographic frontal alpha asymmetry (FAA) has been suggested to be a clinical biomarker for the abnormalities in major depressive disorder (MDD) [1][2][3][4][5][6][7][8][9], conflicting results in prior research have contested this view [10,11]. A previous meta-analysis of 1,883 individuals with MDD and 2,161 healthy controls found that FAA's diagnostic value was not significant [11].…”

Section: Introductionmentioning

confidence: 99%

Comparison of frontal alpha asymmetry among schizophrenia patients, major depressive disorder patients, and healthy controls

Jang¹,

et al. 2020

Preprint

Background: Electroencephalography (EEG) frontal alpha asymmetry (FAA) has been observed in several psychiatric disorders. Dominance in left or right frontal alpha activity remains inconsistent in patients with major depressive disorder (MDD), patients with schizophrenia, and healthy controls. This study compared FAA among patients with MDD and schizophrenia, and healthy controls.Methods: We recruited 20 patients with MDD, 18 patients with schizophrenia, and 16 healthy individuals. The EEG alpha frequency ranged from 8 Hz to 12 Hz. FAA was expressed as the difference between absolute power values of right and left hemisphere electrodes in the alpha frequency range (common-log-transformed frontal right- and left-hemisphere electrodes: F4–F3, F8–F7, FP2–FP1, AF4–AF3, F6–F5, and F2–F1). Hamilton depression and anxiety rating scales were evaluated in patients with MDD. Positive and negative syndrome scales were evaluated in patients with schizophrenia.Results: Patients with schizophrenia showed significantly lower left FAA than healthy controls (F4–F3, schizophrenia vs. healthy controls: -0.10 ± 0.04 vs. -0.05 ± 0.05). There were no significant differences in FAA between patients with schizophrenia and MDD as well as between patients with MDD and healthy controls.Conclusions: The present study suggests that FAA indicates a relatively lower activation of left frontal electrodes in schizophrenia. The left-lateralized FAA could be a neuropathological attribute in patients with schizophrenia, but a lack of sample size and information such as medication and duration of illness might obscure the interpretation and generalization of our findings. Thus, further studies to verify the findings would be warranted.