Quantitative introspection: Measuring knowledge and the feeling of knowledge.
Ever since Wundt the introspective method and the study of mental
chronometry have followed distinct paths. Whereas the introspective
method has led to the flourishing field of metacognitive research
(introspection about mental content, feeling of knowing) chronometric
studies have been most useful in dissecting elementary cognitive
processes from an objective, third-person perspective. In this talk I
will describe recent efforts to bridge this gap. I will show that 1)
Introspective measures are reliable and robust, under certain
circumstances strongly correlated with objective measures, and
amenable to quantitative methodologies used in third-person
neuroscience, 2) Quantitative introspection of internal processing
time revealed that only certain cognitive events –typically related
with flexible computations - are available as internal markers and
accessible to consciousness. 3) Exploring the sense of confidence in a
visual recognition task in a cluttered field, we could identify a
marked double dissociation between objective response and subjective
confidence: instances in which subjects systematically responded
correctly at very low confidence and others in which subjects
responded systematically incorrectly with very high confidence in
their response. Unmasking the elements in the scene (distractors)
which primed incorrect responses we could start assessing
quantitatively the temporal and spatial factors determining access to
an objective response and to subjective reports.