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In three experiments, rats received a single presentation of an auditory conditioned stimulus (CSI beginning simultaneously with an electric grid-shock unconditioned stimulus (US). Later, the CS was presented while the rats licked a drinking tube for water, and CS-elicited suppression of licking was taken as an index of the excitation conditioned to the CS. It was found that conditioning increased as a joint function of the duration of CS-US overlap and US duration. The evidence suggested that weak conditioning due to a brief CS-US overlap could be increased by extending the US beyond CS termination. Extending CS duration beyond US termination, however, did not strengthen conditioning; indeed, extending the CS 60 sec beyond US termination weakened conditioning significantly. It is suggested that these results shed light on a discrepancy in the recent literature on simultaneous conditioning. Mahoney and Ayres (1976) have demonstrated strong excitatory fear conditioning in rats following a single simultaneous pairing of an auditory conditioned stimulus (CS) and an electric grid-shock unconditioned stimulus (US). Here we explore two parameters of that situation: the CS duration and the US duration.The effects of CS duration were of interest partly in their own right and partly because of a discrepancy in the results of a number of investigations of simultaneous conditioning. Specifically, Heth and Rescorla (1973), Mahoney and Ayres (1976), Matsumiya (1960), Mowrer and Aiken (1954), and Siegel and Domjan (1971, Experiment I; 1974, conditioned suppression experiment) all studied the effects of a fearconditioning procedure in which a CS began simultaneously with a shock US. In all of these studies, the CS became excitatory except in those of Siegel and Domjan, in which it became inhibitory.One procedural difference between the experiments of Siegel and Domjan and the others just cited is that Siegel and Dornjan's CS extended at least 59 sec beyond US termination. (presumably because of this feature, Siegel and Domjan called their procedures "backward" conditioning procedures.) In the other studies, the CS and US either terminated together or the CS was terminated first. It seems likely that a long CS extending so far beyond US termination might resemble a CS-alone extinction trial, weakening any excitation possibly conditioned to the CS by virtue of the temporal contiguity of US with CS onset (cf. Mowrer & Lamoreaux, 1942). In the present studies, we tested this idea by initiating CSs and USs simultaneously while varying CS duration across groups. Under some conditions, our CS extended more than 60 sec beyond US termination. EXPERIMENT 1In Experiment I, the duration of an auditory CS was varied across groups in a one-trial simultaneous conditioning procedure. CS durations of 0, 1, 4, 64, and 128 sec were studied. The US duration was 4 sec for all groups. Since extending the CS beyond US termination was hypothesized to act as a CS-alone extinction procedure, we expected conditioning to be weaker in Groups 64 and 128 th...

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The mean response time to 99 stimulus words of the Kent-Rosanoff Word Association Test was used to differentiate creative subjects from two homogeneous groups of psychiatric inpatients, one with depressive disorders and another with schizophrenic disorders. The creative group had significantly faster mean response times than the depressive group. While the schizophrenic group did not differ significantly from the creative or depressive groups, speed of responding in the schizophrenic group ranked both slower than the creative group and a good deal faster than the. depressives. These results do not support previous claims of a connection between depressive illness and creativity. The role of level of creative achievement and social success in relation to depressive symptomatology is briefly discussed.