BACKGROUND: Selective attention involves a dynamic interaction between attentional control systems and brain oscillations. In auditory processing, selective attention toward task-relevant stimuli and the inhibition of irrelevant information can be considered as aspects of top-down attentional control. Oscillatory rhythms in the alpha band have been found to play an important role during top-down processing. Because attention deficits have been noted in patients with schizophrenia, we examined alpha oscillations in schizophrenia and in the prodromal phase of psychosis. METHODS: The present study compared alpha oscillations using measures of both spectral power and inter-trial coherence in 17 subjects at ultra-high-risk, 10 patients with schizophrenia, and 18 matched normal control subjects. Whole-head magnetoencephalography (MEG) was conducted during an auditory oddball task to investigate alpha brain activity related to selective attention to target stimuli and selective inhibition of irrelevant stimuli. RESULTS: Patients with schizophrenia showed diminished alpha event-related desynchronization compared with the control subjects, while the ultra-high-risk subjects had values intermediate between the control subjects and schizophrenia patients. Similarly, alpha inter-trial phase coherence was lower in the schizophrenia patients than the ultra-high-risk subjects, and lower in the ultra-high-risk subjects than the normal control subjects. Furthermore, alpha band activity in the parieto-occipital region was more severely depressed in the schizophrenia patients than the ultra-high-risk subjects. CONCLUSIONS: The altered alpha band activity in the ultra-high-risk group indicates that a deficit in top-down attentional control exists before the onset of psychosis. The alpha event-related desynchronization and inter-trial coherence may reflect a functional decline in the prodromal phase of schizophrenia.
BACKGROUND: Selective attention involves a dynamic interaction between attentional control systems and brain oscillations. In auditory processing, selective attention toward task-relevant stimuli and the inhibition of irrelevant information can be considered as aspects of top-down attentional control. Oscillatory rhythms in the alpha band have been found to play an important role during top-down processing. Because attention deficits have been noted in patients with schizophrenia, we examined alpha oscillations in schizophrenia and in the prodromal phase of psychosis. METHODS: The present study compared alpha oscillations using measures of both spectral power and inter-trial coherence in 17 subjects at ultra-high-risk, 10 patients with schizophrenia, and 18 matched normal control subjects. Whole-head magnetoencephalography (MEG) was conducted during an auditory oddball task to investigate alpha brain activity related to selective attention to target stimuli and selective inhibition of irrelevant stimuli. RESULTS:Patients with schizophrenia showed diminished alpha event-related desynchronization compared with the control subjects, while the ultra-high-risk subjects had values intermediate between the control subjects and schizophreniapatients. Similarly, alpha inter-trial phase coherence was lower in the schizophreniapatients than the ultra-high-risk subjects, and lower in the ultra-high-risk subjects than the normal control subjects. Furthermore, alpha band activity in the parieto-occipital region was more severely depressed in the schizophreniapatients than the ultra-high-risk subjects. CONCLUSIONS: The altered alpha band activity in the ultra-high-risk group indicates that a deficit in top-down attentional control exists before the onset of psychosis. The alpha event-related desynchronization and inter-trial coherence may reflect a functional decline in the prodromal phase of schizophrenia.
Authors: Jürgen Kayser; Craig E Tenke; Christopher J Kroppmann; Daniel M Alschuler; Shiva Fekri; Shelly Ben-David; Cheryl M Corcoran; Gerard E Bruder Journal: Int J Psychophysiol Date: 2013-12-13 Impact factor: 2.997
Authors: Jürgen Kayser; Craig E Tenke; Christopher J Kroppmann; Daniel M Alschuler; Shelly Ben-David; Shiva Fekri; Gerard E Bruder; Cheryl M Corcoran Journal: Int J Psychophysiol Date: 2013-07-13 Impact factor: 2.997
Authors: Lauren E Ethridge; Jordan P Hamm; John R Shapiro; Ann T Summerfelt; Sarah K Keedy; Michael C Stevens; Godfrey Pearlson; Carol A Tamminga; Nash N Boutros; John A Sweeney; Matcheri S Keshavan; Gunvant Thaker; Brett A Clementz Journal: Biol Psychiatry Date: 2012-05-08 Impact factor: 13.382
Authors: Tzvetan G Popov; Brigitte S Rockstroh; Petia Popova; Almut M Carolus; Gregory A Miller Journal: Cogn Affect Behav Neurosci Date: 2014-03 Impact factor: 3.526