The deception literature has predominantly focused on detection
of guilty individuals using electrodermal measures. Little research
has examined other psychophysiological measures or the mechanisms
underlying deception. Therefore, the present study examined pupillary
responses in a differentiation-of-deception paradigm. Twenty-four
undergraduate participants answered the same questions twice, once
truthfully and once deceptively, while pupillary responses were recorded.
Questions were based on recently learned (episodic) information from
scenarios or on general (semantic) knowledge from long-term memory.
Task-evoked pupil dilation was significantly greater when participants
confabulated responses than when they told the truth for both episodic
and semantic memory questions. Previous research has demonstrated that
pupil size increases with increased cognitive processing load. The
present study suggested that generating deceptive recall was associated
with increased pupil size and required greater cognitive processing than