Barba’s (2012) article deftly weaves three main themes in one argument about operant variability. From general theoretical considerations on operant behavior (Catania, 1973), Barba derives methodological guidelines about response differentiation and applies them to the study of operant variability. In the process, he uncovers unnoticed features of operant variability research (e.g., Neuringer, ...

To study the heritability of different training stages of appetitive operant conditioning, we carried out behavioral screening of 5 standard inbred mouse strains, 28 recombinant-inbred (BxD) mouse lines and their progenitor strains C57BL/6J and DBA/2J. We also computed correlations between successive training stages to study whether learning deficits at an advanced stage of operant conditioning...

The effects of bilateral electrolytic subicular lesions were examined on the operant behaviour for food reward on a continuous reinforcement schedule as well as the dendritic morphology of CA1 and CA3 hippocampal areas. The subjects were female Wistar rats 20 days of age and were divided into four groups. 1. Age matched control 2. Sham operated 3. Operant behaviour for food reward and 4. Subicu...

The nucleus accumbens (NAc) has long been thought of as a limbic-motor interface. Despite behavioral and anatomical evidence in favor of this idea, little is known about how NAc neurons encode information about motivationally relevant environmental cues and use this information to affect motor action. We therefore investigated the firing of these neurons during the performance of a discriminati...

Using a discourse analytic qualitative approach, we investigated the naturally-occurring discourse that arose as part of two kinds of regular course activities, synchronous and asynchronous computer-mediated discussions. The messages contributed by members of a graduate course were analyzed for the kind of discourse functions and the kind of politeness strategies they displayed. Results indicat...

O Definition Primarily a feature of certain sentences, e.g., of many ascriptions of propositional attitudes. The truth of such ascriptions does not systematically depend on the truth or falsity of the proposition involved. Consider the following two belief-ascriptions: “Mary believes that 1 + 1 = 2” and “Mary believes that 2756 + 488 = 3244.” Even though both propositions (“1 + 1 = 2” and “2756...

Operant behavior is behavior "controlled" by its consequences. In practice, operant conditioning is the study of reversible behavior maintained by reinforcement schedules. We review empirical studies and theoretical approaches to two large classes of operant behavior: interval timing and choice. We discuss cognitive versus behavioral approaches to timing, the "gap" experiment and its implicatio...

WE are interested in the behavior of an organism because of its effects on the environment. (One effect on the social environment is, of course, the arousal of our interest.) Some effects seem to throw light on the behavior which produces them, but their explanatory role has been clouded by the fact that they follow the behavior and, therefore, raise the specter of teleology. An attempt has bee...