Multichannel Systems MC_Rack Manual - Manual (Page 191)

Glossary
185
O
OTC: Organotypic Culture: An MEA experiment where the slice is cultured on the MEA for weeks
or months, in contrast to an acute slice experiment.
P
peak-peak: Interval from maximum to minimum signal
PPD: Paired Pulse Depression
PPF: Paired Pulse Facilitation
R
Real-time Feedback: The real-time feature allows the user to generate TTL signals in response to
defined signal patterns detected by one or several electrodes. These TTL signals in turn can control
a stimulus generator (STG) to deliver feedback stimulation to the biological sample within a time
frame of one millisecond after the actual event..
ROI: Region of interest: In triggered operation mode, the Analyzer extracts parameters from
a user-defined region of interest.
S
Savitzky Golay Filter: IThe parameters of the Savitzky-Golay filter are the order (2 or 4) and the
number of points which are included from the right and the left side of a data point for averaging
the calculated data point (2, 4, 8, 16, 32, 48). This filter can be used to smooth a noisy signal.
However, it is possible to accidental filter out fast signals, like spikes. those in a specific range
to very low levels. A bandstop filter with a high Q factor has a narrow stopband.
spike: A field potential that is the extracellular representation of an action potential. The spike
rate reflects the intensity of activity. In comparison with LFPs, it is a higher frequency signal. To
obtain only spikes (without LFPs), a 300 Hz high-pass filter can be used.
T
triggered recording: A non-continuous recording of cutouts around a trigger event, for
example, for recording evoked responses. The cutout size is selected in the Recorder. Note that
the data in-between the cutouts is lost permanently.
TTL: Transistor-Transistor Logic. Digital signal for communication between two devices. A voltage
between 0 V and 0.8 V is considered as a logical state of 0 (LOW), and a voltage between 2 V and
5 V means a 1 (HIGH).
U
upper cutoff frequency: Between the lower cutoff frequency and the upper cutoff frequency
of a frequency band is the resonant frequency, at which the gain of the filter is at its maximum.
Signal components with a higher frequency than the upper cutoff frequency of a band pass filter
are attenuated.
W
Windows Meta File (WMF): Intermediate exchange format for 16-bit Windows applications,
limited vector graphics support, file extension *.wmf