Five experiments investigated the development of aversions to stimuli with strong odor components. Those odors were presented simultaneously with tastes are followed by lithium chloride. Contrary to expectations derived from previous investigations of compound conditioning, the presence of a taste stimulus at the time of conditioning was found to potentiate rather than overshadow the resulting odor aversions. Explanations in terms of either the taste's unconditioned aversiveness or nonassociative effects were found to be inadequate. An alternative interpretation attributing potentiation to the summed effects of within-compound odor-taste associations and odor-unconditioned stimulus associations was suggested. In agreement with such an interpretation, evidence of odor-taste associations was found in this situation. Furthermore, continued aversiveness of the taste was necessary for potentiation of the odor aversion to occur. An account of potentiation in terms of within-compound associations makes the phenomenon compatible with modern theories of Pavlovian associations.

Context-unconditioned-stimulus (US) associations have been suggested as the mediator of the response decrement that occurs when extra USs are added to the intertrial intervals (ITIs) of an otherwise standard Pavlovian conditioning situation. The present autoshaping experiments were concerned with the effect of signaling those extra USs, since such signaling might be expected to lessen their ability to condition the context. Experiments 1 and 2 showed that signaling the ITI USs did reduce their detrimental effects on responding to the conditioned stimulus (CS). To determine whether that reduction was due to an impact of signaling on the target-CS-US association or on performance to the target-CS, Experiment 3 examined responding to differentially trained CSs in a common context, as well as responding to identically trained CSs in differentially trained contexts. Whether the CS was tested in a context of relatively high or low associative strength, more responding occurred to the CS trained with signaled, as compared with unsignaled, ITI USs; further, there was more responding to that CS in the more highly valued context. The pattern of results suggests that contextual value does interact with CS-US learning and may also affect performance to the CS.

The data indicate that possible "depletion" of episodic memory capacity and/or glucose-mediated resources in the brain due to performing a concomitant cognitive task might be crucial to the demonstration of a glucose facilitation effect. Possible implications regarding underlying cognitive and physiological mechanisms are discussed in this article.

The results of this study further support the hypothesis that glucose administration can enhance certain aspects of memory performance in healthy young adults. More significantly, the findings indicate that this cognitive facilitation effect persists under more naturalistic conditions of glucose administration and is not restricted to long fast durations or morning administration.

The effect of color on the expected and experienced refreshment, intensity, and liking of lemon, mint, and vanilla beverages was studied. Subjects rated the expected and actual taste of brown lemon and mint solutions as less refreshing than the tastes of differently colored solutions of the same flavor. However, the refreshment ratings (expected and actual) of the brown vanilla beverage were not different from those of the vanilla beverages of other colors. Liking ratings also depended on color in a manner similar to that of the refreshment ratings. Intensity ratings also varied with color. However, unlike when subjects smell solutions rather than taste them, colored solutions were not judged as more intense than colorless ones. In fact, the clear solutions were judged as strongest.