Ethmoid sinus disease and nasal septal deformities as etiologies of chronic cephalgia: results of surgical management.

Results of a retrospective chart review of 80 patients, in conjunction with recently completed questionnaires, document the effects of sinus and nasal surgeries on chronic headache symptoms believed to originate within the ethmoid sinuses or nose. Seventy (88%) of the patients in this study experienced a dramatic improvement of their headache symptoms after undergoing surgical treatment. The authors conclude that this type of cephalgia is more common than expected, that its cause goes largely undiagnosed by the majority of physicians, and that an effective method of treatment is available to improve the quality of life of these patients.

Gamma-butyrolactone's discriminability and effect on low rates of lever pressing by rats: alone and in combination with D-amphetamine and naloxone.

Three studies examined gamma-butyrolactone (Gbl) for benzodiazepine-like effects on low rates of food reinforced lever pressing by rats. A fourth study established Gbl's discriminative properties. Additionally, d-amphetamine or naloxone was administered with Gbl to test hypotheses of Gbl's neurochemical mechanisms of action. In Experiment 1, Gbl caused a dose-related decrease in lever pressing during a fixed-interval reinforcement schedule. Contrary to previous reports, neither d-amphetamine nor naloxone reversed the depressive effects of a high dose of Gbl on behavior. In Experiment 2, Gbl increased lever pressing which had been suppressed in the presence of a tone correlated with response-independent foot-shock (conditioned suppression). These results are consistent with, and extend, previous findings of benzodiazepine-like antipunishment effects of Gbl. However, in Experiment 3, when brief electric shocks were presented after each lever press, Gbl did not increase lever pressing. These results show the limited generality of Gbl's antipunishment effect compared to broad spectrum anxiolytics. Experiment 4, a drug discrimination study, showed rats readily discriminated 150 and 125 mg/kg Gbl from saline. However, neither d-amphetamine nor naloxone generalized to the Gbl lever. Amphetamine partially blocked the discriminative properties of 150 mg/kg Gbl, whereas naloxone had little effect on Gbl's discriminative properties. Thus, there is some support for a direct catecholaminergic role in Gbl-related seizures and little support for opioid receptor participation. The results of Experiments 1 and 4 indicate that Gbl's effects on behavior are complex, and are not accounted for by hypotheses involving only catecholamine and/or opioid mechanisms of action.

Conditional relations by monkeys: Reflexivity, symmetry, and transitivity.

Two cynomolgous macaques categorized six colors into two groups of three after conditional discrimination training (zero-delay symbolic match-to-sample). The procedures resulted in the establishment of relations among the elements of each set-relations that were not specifically trained and that can be characterized by the properties of reflexivity, symmetry, and transitivity. Each set of colors was related to a characteristic pattern of responding: One response pattern involved temporal duration (press and hold the response keys); the second response pattern entailed repeated pressing and releasing of the response keys (fixed ratio 8). Six combinations of two colors were trained, three combinations from each set. After discriminative performance stabilized for each monkey, they were tested with 10 additional color combinations, all of which differed from the training combinations. The conditional relations established between test combinations can be characterized as stimulus equivalence. The training procedures were analogous to the procedure of using category names, and have implications for understanding the function of language in the formation of equivalence classes.

Gamma-butyrolactone increases the rate of punished lever pressing by rats.

Four rats lever pressed for food on a two component multiple FR-VI schedule of reinforcement. In the FR component a brief electric shock coincided with the presentation of food. After level pressing stabilized in the presence of the shock, drugs were administered in two phases. In Phase 1, one of four doses of either gamma-butyrolactone or sodium pentobarbital was injected before sessions. Both drugs increased lever pressing rates during the shocked component of the schedule at doses which did not affect lever pressing rates during the unshocked component. In Phase 2, one of four doses of a mixture of the two compounds was injected. The drug mixture increased rates of punished lever-pressing to levels similar to those reached in Phase 1. These results confirm previous findings for sodium pentobarbital and indicate that gamma-butyrolactone warrants further investigation into its behavioral properties.