DIMENSIONS COGNITIVES ET COMPORTEMENTALES CHEZ LES JOUEURS RÉGULIERS ET OCCASIONNELS AU BLACKJACK

Empirical studies in the psychology of gambling have revealed at least two well supported findings: (1) irrational cognitions outnumber rational cognitions during gambling (Gaboury and Ladouceur, 1987; Ladouceur, Gaboury, Dumont and Rochette 1988); (2) risk-taking behavior increases as a function to exposure to gambling activities (Ladouceur, Mayrand and Tourigny 1987; Ladouceur, Tourigny and Mayrand 1986). The present study compared regular and occasional gamblers on cognitive and behavioral measures during a blackjack session using the thinking aloud method. The results confirmed that regular players emitted more irrational thoughts than occasional gamblers. The theoretical and practical implications of those results are discussed within the general context of the psychology of gambling.     

Stereo-motion cooperation and the use ofmotion disparity in the visual perception of 3-D structure

When an observer views a moving scene binocularly, both motion parallax and binocular disparity provide depth information. In Experiments lA-1C, we measured sensitivity to surface curvature when these depth cues were available either individually or simultaneously. When the depth cues yielded comparable sensitivity to surface curvature, we found that curvature detection was easier with the cues present simultaneously, rather than individually. For 2 of the 6 subjects, this effect was stronger when the component of frontal translation of the surface was vertical, rather than horizontal. No such anisotropy was found for the 4 other subjects. If a moving object is observed binocularly, the patterns of optic flow are different on the left and right retinae. We have suggested elsewhere (Cornilleau-Pérès & Droulez, in press) that this motion disparity might be used as avisual cue for the perception of a 3-D structure. Our model consisted in deriving binocular disparity from the left and right distributions of vertical velocities, rather than from luminous intensities, as has been done in classical studies on stereoscopic vision. The model led to some predictions concerning the detection of surface curvature from motion disparity in the presence or absence of intensity-based disparity (classically termedbinocular disparity). In a second set of experiments, we attempted to test these predictions, and we failed to validate our theoretical scheme from a physiological point of view.