In two studies, subjects read and rated how well they understood a poe
m. Beforehand, however, they had participated under hypnosis in an exe
rcise designed to induce feelings of being uncertain about something.
For half of the subjects hypnosis was made salient as a cause for the
feelings; for the other half the feelings remained unexplained The res
ults showed that when left unexplained, the feelings of uncertainty we
re interpreted by subjects as indications that they did not understand
the poem. When attributed to the hypnosis, however, the feelings had
no effect on ratings of comprehension. In one experiment, subjects wer
e also studied who were not susceptible to hypnosis, and who, therefor
e, did not feel uncertain in the first place. The results suggest that
just as positive and negative affective feelings serve as information
for making evaluative judgments, feelings of certainty and uncertaint
y serve as information for making cognitive judgements (i.e. judgments
of knowing).