Sympathetic nervous system (SNS) activity provides objective data for
assessing emotional reactions. Electrodermal Activity (EDA) is a popular SNS
measure. EDA is basically an index of the electrical activity of the skin; sweat
glands in the skin are filled with tiny amounts of sweat and sweat contains ions
that conduct current, which can be detected and recorded. Increases in EDA
reflect increases in sympathetic nervous SNS activity. EDA is also referred to
as skin conductance (SCR, SCL, etc.) or galvanic skin response
(GSR).
Significantly, EDA can provide time-stamped information for
moment-to-moment reaction measurement throughout a message/stimulus presentation
(such as an advertisement).Combining physiological data with self-reported data
helps provide a more complete, more accurate understanding of a participant’s
emotional reactions. Unobtrusive, wearable wireless physiology devices (such as BioNomadix
BN-PPGED from BIOPAC Systems, Inc.) can
provide continuous and precise measures of nervous system activity, such as EDA,
ECG, and RSP.
Read
a case study at “Hooked on a Feeling: Implicit Measurement of Emotion Improves Utility of Concept Testing.” Researchers conducted a message-testing study in which
they measured physiological
arousal (via EDA), emotional valence (via continuous rating dial data), and discrete
emotions (retrospectively reported emotional
reactions), among other measures. Researchers used a BIOPAC MP150 data
acquisition system and wireless EDA BioNomadix module to collect EDA while
participants viewed each ad, and a BIOPAC variable assessment transducer to
assess in-the-moment feelings of positivity or negativity. E-Prime was used to
allow for precise synchronization across stimuli presentation and data
collection.
