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Three experiments investigated the directed skeletal movements of pigeons toward signals of food or no food. Pigeons approached and pecked an illuminated key that was positively correlated with food delivery and positioned themselves relatively far from an illuminated key that was negatively correlated with food delivery. Key illuminations alone, random presentations of key illuminations and food, and backward pairings of key illuminations and food did not produce keypecking or consistent approach/ withdrawal. Therefore, directed skeletal behavior-often believed to be conditioned and maintained primarily or exclusively by "operant" procedures-also emerges on "Pavlovian" procedures. Several kinds of alternative explanations (e.g., conditioned reinforcement effects, stimulus substitution) for these phenomena were considered, and some potential implications for operant discrimination learning were briefly explored.Pavlovian conditioning involves the presentation of stimulus events independently of an animal's behavior. Most research with this procedure has employed restrained subjects and types of responses (e.g., glandular, visceral, and some skeletal responses like eye blinks and knee jerks) that cannot be directed toward or away from stimuli in the the environment. Recently, however, several studies have examined the directed skeletal behavior of freely moving subjects in situations that otherwise fulfill the usual defining criteria of Pavlovian conditioning. For example, in their work on autoshaping, Brown and Jenkins (1968) found that pigeons approached and pecked a small circular key whose brief illumination (conditioned stimulus, or CS) signaled the imminent presentation of grain (unconditioned stimulus, or

N-[(3R)-1-Azabicyclo[2.2.2]oct-3-yl]furo[2,3-c]pyridine-5-carboxamide (14, PHA-543,613), a novel agonist of the alpha7 neuronal nicotinic acetylcholine receptor (alpha7 nAChR), has been identified as a potential treatment of cognitive deficits in schizophrenia. Compound 14 is a potent and selective alpha7 nAChR agonist with an excellent in vitro profile. The compound is characterized by rapid brain penetration and high oral bioavailability in rat and demonstrates in vivo efficacy in auditory sensory gating and, in an in vivo model to assess cognitive performance, novel object recognition.

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The α4β2* PAM NS9283 alone did not produce nicotine-like discriminative effects, but did demonstrate dose-related increases in nicotine lever choice when combined with a non-effective dose of nicotine or the α4β2* agonist ABT-594. This finding provides confirmation of the positive allosteric modulating effect of NS9283 in a functional in vivo paradigm. NS9283 is a potentially valuable tool for studying the role of α4β2* receptors in various nicotinic acetylcholine receptor-related functions.