Chapter 21 – Oscillations and Behavior: The Role of Phase–Amplitude Coupling in Cognition

Neuronal oscillations play a fundamental role in normal brain functioning. The coupling between oscillations across the same or different frequency bands is essential for neuronal computation and information integration across areas and time scales. An increasingly investigated form of neuronal coupling is phase–amplitude cross-frequency coupling (PAC), in which the phase of a lower-frequency oscillation modulates the power of a higher-frequency oscillation or spiking activity. In this chapter we review evidence for the mechanisms underlying PAC and the role that it may play in cognition, including perception, attention, and memory. We review recent models suggesting that phase-coding and phase–amplitude coupling are used to efficiently encode input and reorganize local neuronal activity during speech perception, short-term memory, and visual perception. Finally, we discuss evidence for alterations in PAC under various neurological conditions and the use of scalp electroencephalogram as a potential noninvasive tool to assess PAC.