The role of nasal chemical senses in garter snake response to airborne odor cues from prey.

Garter snakes increase tongue-flick rates in the presence of airborne odorants (amyl acetate, limonene, earthworm wash vapor, fish water vapor, earthworms, goldfish) but not water vapor. Main olfactory (MO) nerve lesions result in loss of this tongue-flick rate elevation in the presence of airbome odorants. Vomeronasal (VN) nerve lesions result in a diminution of tongue-flick rate elevation. Garter snakes discriminate between the 2 arms of a maze containing airbome earthworm odor as compared with a blank control. Following MO nerve lesions, snakes fail to make this discrimination. Following VN nerve lesions or VN duct suture, snakes are initially able to make the discrimination but may eventually cease to prefer the prey-odor side of the maze and may stop eating prey rewards. These results support the idea that airbome odorants are detected by the main MO system and that such detection does not require a functional VN system. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Cardiovascular stimulation induced by rapid increases in desflurane concentration in humans results from activation of tracheopulmonary and systemic receptors

BACKGROUND: It was hypothesized that stimulation of rapidly adapting airway receptors produces the transient (2-4 min) circulatory responses to rapid increases in desflurane concentrations greater than 6%. Accordingly, it was reasoned that increasing the concentration of desflurane in one lung, without altering the concentration of desflurane in systemic blood, should cause cardiovascular stimulation, whereas once the airway receptors had adapted to the stimulation, an initial increase in the systemic concentration of desflurane should have little effect. METHODS: After placement of a double-lumen endotracheal tube in four volunteers and establishment of a steady-state level of 4% desflurane in both lungs, the desflurane concentration was rapidly increased from 4% to 8% in one lung while decreasing it in the other, thereby obviating any increase in the systemic desflurane blood concentration (confirmed by analysis). After returning the desflurane end-tidal concentration to 4% in both lungs, this process was repeated for the contralateral lung thereby having exposed both lungs to 8% desflurane without increasing the systemic desflurane concentration. After returning desflurane concentration to 4%, it was increased in both lungs simultaneously to 8% and consequently in blood to 8% of an atm. RESULTS: Rapid increases in desflurane concentrations in either lung, but not blood, significantly increased heart rate (17 +/- 5 beats/min, mean +/- SE, P < 0.05) and mean arterial blood pressure (15 +/- 5 mmHg, P < 0.05), but a greater increase in heart rate (43 +/- 5 beats/min, P < 0.05) and mean arterial blood pressure (46 +/- 11 mmHg, P < 0.05) occurred when both lungs were exposed simultaneously to rapidly increased desflurane concentration for the second time within 90 min. This result did not differ from the increase occurring on another day when both lungs and blood were exposed for the first time that day to 8% desflurane (heart rate 40 +/- 7 beats/min, P = 0.8; mean arterial blood pressure 40 +/- 3 mmHg, P = 0.5). CONCLUSIONS: It was concluded that at least two sites respond to a rapid increase in desflurane concentrations greater than 6%: one site in the airways and/or lungs, and at least one other in a highly perfused tissue(s). The systemic site contributes more importantly.     

A prevention programme for drinking driving

A drinking-driving programme introduced in one borough of Toronto, Canada, is evaluated. Based on evidence from previous programmes judged effective, it combined a highly visible “random” spot-check enforcement component with a drinking-driving educational component. A three-wave telephone survey showed significant increases in public knowledge of drinking and driving and of the programme in the experimental area. The subjective perception of arrest risk was increased for the “average driver” but not for “myself”. Unfortunately, only indirect evidence was available on driver behaviour and this tended to indicate fewer impaired drivers on the road. Finally, police reported alcohol-related accidents and injuries indicated an overall downward trend in Toronto, but the urban nature and restricted size of the experiment's geographic unit, as well as similar changes in control areas and contaminations to the data rendered the analysis highly ambiguous. Thus, the programme experienced some positive although by no means conclusive indicators of success.     

Failure of posthypnotic responding to occur outside the experimental setting.

Ten highly hypnotizable subjects and two groups of 10 nonhypnotizable simulators were formally tested for posthypnotic responding in two experimental sessions. All subjects passed at least three of the four formal tests. Between the formal test session, subjects were administered three informal tests in which the posthypnotic cue word was presented outside of the experimental context. Two of these informal tests were conducted by confederates who were unknown to any of the subjects, and the third informal test was conducted by the hypnotist. About half of the subjects in each group responded to the informal cue given by the hypnotist. However, none of the subjects in any group responded to the informal cue given by Confederate 1, and only 1 simulator and none of the high hypnotizables responded to the informal cue given by Confederate 2. These findings support the hypothesis that posthypnotic responding is expectancy-mediated, goal-directed action. (PsycINFO Database Record (c) 2010 APA, all rights reserved)