Judgment of contingency: cognitive biases in depressed and nondepressed subjects

In this research I investigated whether the use of relevant affective outcomes influences depressed and nondepressed subjects' judgment of contingency. Similar to previous studies (Alloy & Abramson, 1979, Experiments 1 and 2), Experiments 1 and 2 confirmed that when the outcome is affectively neutral (i.e., the onset of a light) depressed subjects make accurate judgments of contingency, whereas nondepressed subjects show (in noncontingent situations) a significant illusion of control. In Experiments 3 and 4 (a contingency situation and a noncontingency situation, respectively) different types of sentences (negative self-referent, negative other-referent, positive self-referent, positive other-referent) were used as outcomes. Although depressed subjects were more reluctant to show biased judgments than were the nondepressed subjects, in noncontingency situations depressed subjects made overestimated judgments of contingency when the outcomes were negative self-referent sentences. Results are discussed with regard to current cognitive theories of depression, particularly the learned helplessness model.     

Rational understanding: toward a probabilistic epistemology of acceptability

Synthese - To understand something involves some sort of commitment to a set of propositions comprising an account of the understood phenomenon. Some take this commitment to be a species of belief;...     

The effects of signalled and unsignalled lick-dependent delays on the development of schedule-induced drinking in rats

Food pellets were programmed to be delivered to rats every 60 sec (Fixed Time 60-sec schedule), and the development of schedule-induced drinking was measured in terms of the amount of water consumed and the number of licks per inter-pellet interval. For some rats (masters) 10-sec delays in food delivery were dependent on licks. Yoked-control rats received food at the same time as their masters and independently of their own behaviour. In Experiment 1, in which the delays were signalled by a blackout, the master rats began to drink, but this schedule-induced behaviour then decreased to levels lower than those shown by the yoked controls. When the signalled delays were discontinued, the drinking of the master rats recovered. In Experiment 2, in which the delays were not signalled, the master rats did not develop as much schedule-induced drinking as the yoked controls, and discontinuing the delays led to only small increases in drinking. These results support the view that schedule-induced drinking is subject to control by its consequences.