Arguably the preeminent task of cognitive neuroscience is to explain how the brain implements cognitive processes such as perception, attention, memory, decision-making, and consciousness. It is becoming commonplace to propose that such cognitive processes are implemented through the activity of networks of functionally specialized brain regions, forming and dissolving on a time scale of tens to hundreds of milliseconds. In this first lecture, I will review some of the current knowledge about one mechanism that is likely to be deeply involved in forming and dissolving these networks, and in the communication within them: neural synchronization. Neural synchronization refers to the idea that oscillations of activity, within a particular narrow band of frequencies, of one group of neurons can become transiently phase-locked with that in another group of neurons. Such transient phase locking can play a number of roles, including facilitating communication of information between the neural groups and even performing computational functions. Modulations of theta (4-7 Hz), alpha (8-15 Hz), and gamma (30-50 Hz) synchronization in the EEG and MEG, both within and between brain regions, have all been shown to be associated with cognitive function, including perception, memory, attention, and consciousness. I will review a few of the most important of these results, and then discuss in detail one such result from my own laboratory involving detection of changes in the ongoing stimulus environment.
17:00 à 18:00
