Fluctuations in instantaneous frequency predict alpha amplitude during visual perception

• Published in: Nature communications Vol. 8; no. 1; pp. 2071 - 12
• Main Authors: Nelli, Stephanie, Itthipuripat, Sirawaj, Srinivasan, Ramesh, Serences, John T.
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 12.12.2017; Nature Publishing Group; Nature Portfolio
• Subjects: 631/378/116/2393; 631/378/2649/1723; Adult; Brain; Complex systems; Data processing; Discrimination Learning - physiology; EEG; Electroencephalography; Female; Fluctuations; Healthy Volunteers; Humanities and Social Sciences; Humans; Information processing; Male; multidisciplinary; Oscillators; Periodicity; Rhythms; Science; Science (multidisciplinary); Software; Visual aspects; Visual Cortex - physiology; Visual discrimination; Visual perception; Visual Perception - physiology; Visual tasks; Young Adult
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-017-02176-x

Rhythmic neural activity in the alpha band (8–13 Hz) is thought to have an important role in the selective processing of visual information. Typically, modulations in alpha amplitude and instantaneous frequency are thought to reflect independent mechanisms impacting dissociable aspects of visual information processing. However, in complex systems with interacting oscillators such as the brain, amplitude and frequency are mathematically dependent. Here, we record electroencephalography in human subjects and show that both alpha amplitude and instantaneous frequency predict behavioral performance in the same visual discrimination task. Consistent with a model of coupled oscillators, we show that fluctuations in instantaneous frequency predict alpha amplitude on a single trial basis, empirically demonstrating that these metrics are not independent. This interdependence suggests that changes in amplitude and instantaneous frequency reflect a common change in the excitatory and inhibitory neural activity that regulates alpha oscillations and visual information processing. Though the amplitude and frequency of neural oscillations in the alpha band are related to dissociable visual processes, they are not independent mathematically. Here, the authors show that fluctuations in instantaneous frequency predict alpha amplitude during visual discrimination tasks.