The following MPEG-movies show the spatiotemporal patterns of neural magnetic activity recorded from a human subject in three different conditions:

(1) Listening to tones that were delivered with a delay of about 5s. A random time was added to prevent stimulus prediction. The signal is an average over about 80 stimulus presentations.

Auditory evoked fields (MPEG 323K)

(2) Reacting to acoustic stimuli. The same stimulus presentation as in (1) but now the subject was told to press on an air cushion as soon as possible after the tone was heard.

Reacting to an auditory stimulus (MPEG 556K).

(3) Synchronizing with a rhythm. Here the tones were presented regularly with a frequency of 1 Hz. The subject was told to press the air cushion in synchrony with the stimulus.

Synchronizing to rhythmic tones (MPEG 668K).

 

The signals were interpolated in space to obtain a smooth pattern using a two-dimensional spline technique. The white vertical line indicates the point in time for the frame with respect to the stimulus (green line) and the response (yellow line). The time is given in milliseconds with respect to the onset of the stimulus.

The MEG-data were recorded using the CTF system at the Brain Behavior Laboratory, Simon Fraser University, Burnaby, Canada (Director H. Weinberg).