![](bg6.png)
Figure 6: The three figures show the differentiation between moods by mean SCL (in normalized units (n.u.)) for the three
methods discussed. The time in minutes during the mood induction is presented on the horizontal axis. The dotted
(continuous) lines indicate the positive (negative) mood condition. Error bars indicate the standard error.
5 CONCLUSIONS
We propose a method to adjust the skin conductance
signal in order to better reflect mood. It is based on
the observation that SCRs, which frequently occur
on top of the tonic SCL, correspond to event type
stimuli that are not related to mood. The SCR
subtraction method removes these phasic influences
from the SC signal by subtracting the SCRs from the
SC so that an estimate of the pure SCL signal
remains. We validate the SCR subtraction method
with SC data taken in a mood induction experiment.
The results show that the SCR subtraction method
outperforms the alternative SCL estimations. In fact,
the SCR subtraction technique is the only method
resulting in significant differences between the
positive and negative moods.
Using the method we present, skin conductance
can serve as a robust indicator for positive versus
negative mood. Whenever someone’s mood can be
measured, steering one’s mood, or creating
awareness of one’s mood, is only one step away. As
mentioned in the introduction, the range of possible
applications is very broad, including systems that
help in making us feel better, and healthier.
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