Exhibit 15.18 Cognitive-affective rating for two advertisements, based on scales used by Advanced Brain Monitoring’s B-Alert EEG.
Cognitive-affective metrics pertain to the cortical processes underlying mental workload or drowsiness. They
provide a measure of the level of fatigue, attention, engagement and workload that the respondent’s brain is
experiencing.
Cognitive States: Advanced Brain Monitoring’s (ABM) B-Alert EEG uses a scale ranging from 0 to 1 to
gauge the extent that the respondent is tuned-out/attentive. There are 4 cognitive states on this scale — drowsiness &
fatigue onset, distraction, low engagement and high engagement. Each of these states is characterized by different signals.
The signs of drowsiness and fatigue for instance include higher delta band activity and theta bursts.
Workload: ABM also adopts a workload scale, also from 0 to 1, that gauges cognitive processes
dealing with working memory, problem solving and analytical reasoning. There are 3 workload states — boredom, optimum and
stress/information overload. This scale correlates with theta band activity; as theta power increases, so does workload.
Plotted over the epochs, these metrics show how cognitive affective states change over the duration of a stimulus
such as a video advertisement.
The overall performance may be summarized by taking the averages across the epochs. This
allows for comparison across two or more stimuli. Exhibit 15.18, for instance, where ad B with high overall level of engagement
and optimum workload, out-performs ad A which is distracting and relatively boring.
