Considering the design features of this paradigm, Lange and
Eggert’s (2014) experiment exposed participants to the same act
of self-control twice. As a consequence, their design failed to control
for the impact of cognitions or affective experiences that develop
during self-control operations, on willingness to exercise selfcontrol.
This methodology might have ‘masked’ the proposed glucose
effects in their studies for a number of reasons. The reasons include
(i) development of response strategies that diminish the need to
rely on self-control resources and, as a result, the need for glucose
(Study 1); (ii) enhanced levels of boredom that participants might
have experienced as a result of engaging in the same self-control
task twice (Study 1); and (iii) low levels of optimism and selfefficacy
that might have been developed as a result of receiving
negative feedback (Study 2). These factors may have introduced confounds
which masked the glucose effect on self-control in their
experiments. Importantly, the experiments are inconsistent with the
widely-used dual-task paradigm rife in the depletion literature. For
their study to make a viable and robust test of the glucose effect, a
high-powered, precise replication of an experiment using two separate
tasks that have been previously adopted in the depletion
literature seems to be the minimum criterion.