[Eeglablist] Power spectrum question

[xavier corominas]

Dear all,

i'm contacting for assistance.
After pre-processing my data with eeglab from a 8 channel eeg device, i
want to inspect the data plotting a power spectrum density map ( by means
of the -->Plot-->channel spectra and maps functions from the eeglabGUI).
The graphic that is generated contains data scaled negatively in the Y-axis
indicating large negative power spectral values.

Could you help me to understand why this is happening to my data and how to
solve it? (find attached to the mail the spectral map generated).

Thanks in advance for your help.

Xavier.