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P Cloutier

Publications and source records attributed to P Cloutier.

25 records · Page 2Linked to original sources
PubMed1992

Metacognition in psychophysical judgment: an unfolding view of comparative judgments of mental workload.

An experiment is reported in which it was found that when subjects were required to indicate which of two visual extents was more difficult to categorize as "long" or "short," they executed these categorizations and then measured the distance of the representation of each stimulus from the long-short category boundary; the stimulus nearer the boundary was judged to be the more difficult. When they were requested to indicate which was easier to categorize, they selected the alternative that was farther. Coombs's theory of data (1952, 1964) and his unfolding theory of preferential choice (1950, 1964) provided the conceptualization of metacognition in this psychophysical task context. Strong support for the probabilistic version of unfolding theory was obtained from the observed selective effects of laterality on the levels of stochastic transitivity attained for various classes of triples and the reliably longer times for comparisons with bilateral pairs than with unilateral pairs. The semantic congruity effects obtained, together with the changes in the form of the relationship between probability and response time as a function of practice, can be best accounted for by an evidence accrual theory in which the distances from the active reference point are measured and compared with a criterion on each evidence accrual. No support is provided for the view that propositionally based semantic "ease"-"difficulty" codes serve as the basis for these metacognitive comparative judgments of ease and difficulty.

Adult↗
PubMed1991

A purified saponin acts as an adjuvant for a T-independent antigen.

Three strains of mice were injected with a T-independent antigen, Escherichia coli 055:B5 polysaccharide (PS) combined with purified saponin, QS-21, isolated from Quillaja saponaria bank. PS was prepared by hydrolysis of lipopolysaccharide (LPS). Nine week old mice were injected intradermally with 60 micrograms PS, as determined by an anthrone assay, with or without 15 micrograms QS-21 on days 0 and 14. On day 22 sera were assayed by EIA for PS specific antibodies. Titers were 11-fold higher in CD-1 mice with QS-21. C3H/HeJ (Ipsd) and C3H/HeSnJ (Ipsr) mice also showed an adjuvant associated increase in titer with saponin. Therefore, LPS responsiveness was not required for the adjuvant effect. PS vaccinated C3H and CD-1 mice with and without QS-21 had similar antibody isotype profiles. IgG2b titers accounted for more than half of the total Ig response. IgG2a was next highest followed by IgG3, IgM, IgG1, and IgA. In comparison, CD-1 mice injected with 0.1 microgram intact LPS had a different LPS specific isotype profile. IgG3 was the highest followed by IgG1, IgG2b, IgM, IgG2a, and IgA.

Adjuvants, Immunologic↗